Section

[Code of Federal Regulations]
[Title 40, Volume 7]
[Revised as of July 1, 2005]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR60.B]

[Page 602]

Appendix B to Part 60--Performance Specifications

Performance Specification 1--Specifications and test procedures for
continuous opacity monitoring systems in stationary sources
Performance Specification 2--Specifications and Test Procedures for
SO2 and NOX Continuous Emission Monitoring Systems
in Stationary Sources
Performance Specification 3--Specifications and Test Procedures for
O2 and CO2 Continuous Emission Monitoring Systems
in Stationary Sources
Performance Specification 4--Specifications and Test Procedures for
Carbon Monoxide Continuous Emission Monitoring Systems in Stationary
Sources
Performance Specification 4A--Specifications and Test Procedures for
Carbon Monoxide Continuous Emission Monitoring Systems in Stationary
Sources
Performance Specification 4B--Specifications and Test Procedures for
Carbon Monoxide and Oxygen Continuous Monitoring Systems in Stationary
Sources
Performance Specification 5--Specifications and Test Procedures for TRS
Continuous Emission Monitoring Systems in Stationary Sources
Performance Specification 6--Specifications and Test Procedures for
Continuous Emission Rate Monitoring Systems in Stationary Sources
Performance Specification 7--Specifications and Test Procedures for
Hydrogen Sulfide Continuous Emission Monitoring Systems in Stationary
Sources
Performance Specification 8--Performance Specifications for Volatile
Organic Compound Continuous Emission Monitoring Systems in Stationary
Sources
Performance Specification 8A--Specifications and Test Procedures for
Total Hydrocarbon Continuous Monitoring Systems in Stationary Sources
Performance Specification 9--Specifications and Test Procedures for Gas
Chromatographic Continuous Emission Monitoring Systems in Stationary
Sources
Performance Specification 15--Performance Specification for Extractive
FTIR Continuous Emissions Monitor Systems in Stationary Sources

Performance Specification 1--Specifications and Test Procedures for
Continuous Opacity Monitoring Systems in Stationary Sources

1.0 What Is the Purpose and Applicability of Performance Specification
1?

Performance Specification 1 (PS-1) provides (1) requirements for the
design, performance, and installation of a continuous opacity monitoring
system (COMS) and (2) data computation procedures for evaluating the
acceptability of a COMS. It specifies activities for two groups (1) the
owner or operator and (2) the opacity monitor manufacturer.
1.1 Measurement Parameter. PS-1 covers the instrumental measurement
of opacity caused by attenuation of projected light due to absorption
and scatter of the light by particulate matter in the effluent gas
stream.
1.2 What COMS must comply with PS-1? If you are an owner or operator
of a facility with a COMS as a result of this Part, then PS-1 applies to
your COMS if one of the following is true:
(1) Your facility has a new COMS installed after February 6, 2001;
or
(2) Your COMS is replaced, relocated, or substantially refurbished
(in the opinion of the regulatory authority) after February 6, 2001; or
(3) Your COMS was installed before February 6, 2001 and is
specifically required by regulatory action other than the promulgation
of PS-1 to be recertified.
If you are an opacity monitor manufacturer, then paragraph 8.2
applies to you.
1.3 Does PS-1 apply to a facility with an applicable opacity limit
less than 10 percent? If you are an owner or operator of a facility with
a COMS as a result of this Part and the applicable opacity limit is less
than 10 percent, then PS-1 applies to your COMS as described in section
1.2; taking into account (through statistical procedures or otherwise)
the uncertainties associated with opacity measurements, and following
the conditions for attenuators selection for low opacity applications as
outlined in Section 8.1(3)(ii). At your option, you, the source owner or
operator, may select to establish a reduced full scale range of no less
than 50 percent opacity instead of the 80 percent as prescribed in
section 3.5, if the applicable opacity limit for your facility is less
than 10 percent. The EPA recognizes that reducing the range of the
analyzer to 50 percent does not necessarily result in any measurable
improvement in measurement accuracy at opacity levels less than 10
percent; however, it may allow improved chart recorder interpretation.
1.4 What data uncertainty issues apply to COMS data? The measurement
uncertainties associated with COMS data result from several design and
performance factors including limitations on the availability of
calibration attenuators for opacities less than about 6 percent (3
percent for single-pass instruments), calibration error tolerances, zero
and upscale drift tolerances, and allowance for dust compensation that
are significant relative to low opacity levels. The full scale
requirements of this PS may also contribute to measurement uncertainty
for opacity measurements where the applicable limits are below 10
percent opacity.

[[Page 603]]

2.0 What Are the Basic Requirements of PS-1?

PS-1 requires (1) opacity monitor manufacturers comply with a
comprehensive series of design and performance specifications and test
procedures to certify opacity monitoring equipment before shipment to
the end user, (2) the owner or operator to follow installation
guidelines, and (3) the owner or operator to conduct a set of field
performance tests that confirm the acceptability of the COMS after it is
installed.
2.1 ASTM D 6216-98 is the reference for design specifications,
manufacturer's performance specifications, and test procedures. The
opacity monitor manufacturer must periodically select and test an
opacity monitor, that is representative of a group of monitors produced
during a specified period or lot, for conformance with the design
specifications in ASTM D 6216-98. The opacity monitor manufacturer must
test each opacity monitor for conformance with the manufacturer's
performance specifications in ASTM D 6216-98.
2.2 Section 8.1(2) provides guidance for locating an opacity monitor
in vertical and horizontal ducts. You are encouraged to seek approval
for the opacity monitor location from the appropriate regulatory
authority prior to installation.
2.3 After the COMS is installed and calibrated, the owner or
operator must test the COMS for conformance with the field performance
specifications in PS-1.

3.0 What Special Definitions Apply to PS-1?

3.1 All definitions and discussions from section 3 of ASTM D 6216-98
are applicable to PS-1.
3.2 Centroid Area. A concentric area that is geometrically similar
to the stack or duct cross-section and is no greater than 1 percent of
the stack or duct cross-sectional area.
3.3 Data Recorder. That portion of the installed COMS that provides
a permanent record of the opacity monitor output in terms of opacity.
The data recorder may include automatic data reduction capabilities.
3.4 External Audit Device. The inherent design, equipment, or
accommodation of the opacity monitor allowing the independent assessment
of the COMS's calibration and operation.
3.5 Full Scale. The maximum data display output of the COMS. For
purposes of recordkeeping and reporting, full scale will be greater than
80 percent opacity.
3.6 Operational Test Period. A period of time (168 hours) during
which the COMS is expected to operate within the established performance
specifications without any unscheduled maintenance, repair, or
adjustment.
3.7 Primary Attenuators. Those devices (glass or grid filter that
reduce the transmission of light) calibrated according to procedures in
section 7.1.
3.8 Secondary Attenuators. Those devices (glass or grid filter that
reduce the transmission of light) calibrated against primary attenuators
according to procedures in section 7.2.
3.9 System Response Time. The amount of time the COMS takes to
display 95 percent of a step change in opacity on the COMS data
recorder.

4.0 Interferences. Water Droplets

5.0 What Do I Need To Know To Ensure the Safety of Persons Using PS-1?

The procedures required under PS-1 may involve hazardous materials,
operations, and equipment. PS-1 does not purport to address all of the
safety problems associated with these procedures. Before performing
these procedures, you must establish appropriate safety and health
practices, and you must determine the applicable regulatory limitations.
You should consult the COMS user's manual for specific precautions to
take.

6.0 What Equipment and Supplies Do I Need?

6.1 Continuous Opacity Monitoring System. You, as owner or operator,
are responsible for purchasing an opacity monitor that meets the
specifications of ASTM D 6216-98, including a suitable data recorder or
automated data acquisition handling system. Example data recorders
include an analog strip chart recorder or more appropriately an
electronic data acquisition and reporting system with an input signal
range compatible with the analyzer output.
6.2 Calibration Attenuators. You, as owner or operator, are
responsible for purchasing a minimum of three calibration attenuators
that meet the requirements of PS-1. Calibration attenuators are optical
filters with neutral spectral characteristics. Calibration attenuators
must meet the requirements in section 7 and must be of sufficient size
to attenuate the entire light beam received by the detector of the COMS.
For transmissometers operating over a narrow bandwidth (e.g., laser), a
calibration attenuator's value is determined for the actual operating
wavelengths of the transmissometer. Some filters may not be uniform
across the face. If errors result in the daily calibration drift or
calibration error test, you may want to examine the across-face
uniformity of the filter.
6.3 Calibration Spectrophotometer. Whoever calibrates the
attenuators must have a spectrophotometer that meets the following
minimum design specifications:

------------------------------------------------------------------------
Parameter Specification
------------------------------------------------------------------------
Wavelength range.......................... 300-800 nm.
Detector angle of view.................... <10[deg].

[[Page 604]]

Accuracy.................................. <0.5% transmittance, NIST
traceable calibration.
------------------------------------------------------------------------

7.0 What Reagents and Standards Do I Need?

You will need to use attenuators (i.e., neutral density filters) to
check the daily calibration drift and calibration error of a COMS.
Attenuators are designated as either primary or secondary based on how
they are calibrated.
7.1 Attenuators are designated primary in one of two ways:
(1) They are calibrated by NIST; or
(2) They are calibrated on a 6-month frequency through the
assignment of a luminous transmittance value in the following manner:
(i) Use a spectrophotometer meeting the specifications of section
6.3 to calibrate the required filters. Verify the spectrophotometer
calibration through use of a NIST 930D Standard Reference Material
(SRM). A SRM 930D consists of three neutral density glass filters and a
blank, each mounted in a cuvette. The wavelengths and temperature to be
used in the calibration are listed on the NIST certificate that
accompanies the reported values. Determine and record a transmittance of
the SRM values at the NIST wavelengths (three filters at five
wavelengths each for a total of 15 determinations). Calculate a percent
difference between the NIST certified values and the spectrophotometer
response. At least 12 of the 15 differences (in percent) must be within
0.5 percent of the NIST SRM values. No difference
can be greater than 1.0 percent. Recalibrate the
SRM or service the spectrophotometer if the calibration results fail the
criteria.
(ii) Scan the filter to be tested and the NIST blank from wavelength
380 to 780 nm, and record the spectrophotometer percent transmittance
responses at 10 nm intervals. Test in this sequence: blank filter,
tested filter, tested filter rotated 90 degrees in the plane of the
filter, blank filter. Calculate the average transmittance at each 10 nm
interval. If any pair of the tested filter transmittance values (for the
same filter and wavelength) differ by more than 0.25 percent, rescan the tested filter. If the filter
fails to achieve this tolerance, do not use the filter in the
calibration tests of the COMS.
(iii) Correct the tested filter transmittance values by dividing the
average tested filter transmittance by the average blank filter
transmittance at each 10 nm interval.
(iv) Calculate the weighted (to the response of the human eye),
tested filter transmittance by multiplying the transmittance value by
the corresponding response factor shown in table 1-1, to obtain the
Source C Human Eye Response.
(v) Recalibrate the primary attenuators semi-annually if they are
used for the required calibration error test. Recalibrate the primary
attenuators annually if they are used only for calibration of secondary
attenuators.
7.2 Attenuators are designated secondary if the filter calibration
is done using a laboratory-based transmissometer. Conduct the secondary
attenuator calibration using a laboratory-based transmissometer
calibrated as follows:
(i) Use at least three primary filters of nominal luminous
transmittance 50, 70 and 90 percent, calibrated as specified in section
7.1(2)(i), to calibrate the laboratory-based transmissometer. Determine
and record the slope of the calibration line using linear regression
through zero opacity. The slope of the calibration line must be between
0.99 and 1.01, and the laboratory-based transmissometer reading for each
primary filter must not deviate by more than 2
percent from the linear regression line. If the calibration of the
laboratory-based transmissometer yields a slope or individual readings
outside the specified ranges, secondary filter calibrations cannot be
performed. Determine the source of the variations (either
transmissometer performance or changes in the primary filters) and
repeat the transmissometer calibration before proceeding with the
attenuator calibration.
(ii) Immediately following the laboratory-based transmissometer
calibration, insert the secondary attenuators and determine and record
the percent effective opacity value per secondary attenuator from the
calibration curve (linear regression line).
(iii) Recalibrate the secondary attenuators semi-annually if they
are used for the required calibration error test.

8.0 What Performance Procedures Are Required To Comply With PS-1?

Procedures to verify the performance of the COMS are divided into
those completed by the owner or operator and those completed by the
opacity monitor manufacturer.
8.1 What procedures must I follow as the Owner or Operator?
(1) You must purchase an opacity monitor that complies with ASTM D
6216-98 and obtain a certificate of conformance from the opacity monitor
manufacturer.
(2) You must install the opacity monitor at a location where the
opacity measurements are representative of the total emissions from the
affected facility. You must meet this requirement by choosing a
measurement location and a light beam path as follows:
(i) Measurement Location. Select a measurement location that is (1)
at least 4 duct diameters downstream from all particulate control
equipment or flow disturbance, (2) at least 2 duct diameters upstream of
a flow disturbance, (3) where condensed water vapor

[[Page 605]]

is not present, and (4) accessible in order to permit maintenance.
(ii) Light Beam Path. Select a light beam path that passes through
the centroidal area of the stack or duct. Also, you must follow these
additional requirements or modifications for these measurement
locations:

------------------------------------------------------------------------
If your measurement location Then use a light
is in a: And is: beam path that is:
------------------------------------------------------------------------
1. Straight vertical section Less than 4 In the plane defined
of stack or duct. equivalent by the upstream
diameters bend (see figure 1-
downstream from a 1).
bend.
2. Straight vertical section Less than 4 In the plane defined
of stack or duct. equivalent by the downstream
diameters upstream bend (see figure 1-
from a bend. 2).
3. Straight vertical section Less than 4 In the plane defined
of stack or duct. equivalent by the upstream
diameters bend (see figure 1-
downstream and is 3).
also less than 1
diameter upstream
from a bend.
4. Horizontal section of At least 4 In the horizontal
stack or duct. equivalent plane that is
diameters between \1/3\ and
downstream from a \1/2\ the distance
vertical bend. up the vertical
axis from the
bottom of the duct
(see figure 1-4).
5. Horizontal section of Less than 4 In the horizontal
duct. equivalent plane that is
diameters between \1/2\ and
downstream from a \2/3\ the distance
vertical bend. up the vertical
axis from the
bottom of the duct
for upward flow in
the vertical
section, and is
between \1/3\ and
\1/2\ the distance
up the vertical
axis from the
bottom of the duct
for downward flow
(figure 1-5).
------------------------------------------------------------------------

(iii) Alternative Locations and Light Beam Paths. You may select
locations and light beam paths, other than those cited above, if you
demonstrate, to the satisfaction of the Administrator or delegated
agent, that the average opacity measured at the alternative location or
path is equivalent to the opacity as measured at a location meeting the
criteria of sections 8.1(2)(i) and 8.1(2)(ii). The opacity at the
alternative location is considered equivalent if (1) the average opacity
value measured at the alternative location is within 10 percent of the average opacity value measured at the
location meeting the installation criteria, and (2) the difference
between any two average opacity values is less than 2 percent opacity
(absolute). You use the following procedure to conduct this
demonstration: simultaneously measure the opacities at the two locations
or paths for a minimum period of time (e.g., 180-minutes) covering the
range of normal operating conditions and compare the results. The
opacities of the two locations or paths may be measured at different
times, but must represent the same process operating conditions. You may
use alternative procedures for determining acceptable locations if those
procedures are approved by the Administrator.
(3) Field Audit Performance Tests. After you install the COMS, you
must perform the following procedures and tests on the COMS.
(i) Optical Alignment Assessment. Verify and record that all
alignment indicator devices show proper alignment. A clear indication of
alignment is one that is objectively apparent relative to reference
marks or conditions.
(ii) Calibration Error Check. Conduct a three-point calibration
error test using three calibration attenuators that produce outlet
pathlength corrected, single-pass opacity values shown in ASTM D 6216-
98, section 7.5. If your applicable limit is less than 10 percent
opacity, use attenuators as described in ASTM D 6216-98, section 7.5 for
applicable standards of 10 to 19 percent opacity. Confirm the external
audit device produces the proper zero value on the COMS data recorder.
Separately, insert each calibration attenuators (low, mid, and high-
level) into the external audit device. While inserting each attenuator,
(1) ensure that the entire light beam passes through the attenuator, (2)
minimize interference from reflected light, and (3) leave the attenuator
in place for at least two times the shortest recording interval on the
COMS data recorder. Make a total of five nonconsecutive readings for
each attenuator. At the end of the test, correlate each attenuator
insertion to the corresponding value from the data recorder. Subtract
the single-pass calibration attenuator values corrected to the stack
exit conditions from the COMS responses. Calculate the arithmetic mean
difference, standard deviation, and confidence coefficient of the five
measurements value using equations 1-3, 1-4, and 1-5. Calculate the
calibration error as the sum of the absolute value of the mean
difference and the 95 percent confidence coefficient for each of the
three test attenuators using equation 1-6. Report the calibration error
test results for each of the three attenuators.
(iii) System Response Time Check. Using a high-level calibration
attenuator, alternately insert the filter five times and remove it from
the external audit device. For each filter insertion and removal,
measure the amount of time required for the COMS to display 95 percent
of the step change in opacity on the COMS data recorder. For the

[[Page 606]]

upscale response time, measure the time from insertion to display of 95
percent of the final, steady upscale reading. For the downscale response
time, measure the time from removal to display 5 percent of the initial
upscale reading. Calculate the mean of the five upscale response time
measurements and the mean of the five downscale response time
measurements. Report both the upscale and downscale response times.
(iv) Averaging Period Calculation and Recording Check. After the
calibration error check, conduct a check of the averaging period
calculation (e.g., 6-minute integrated average). Consecutively insert
each of the calibration error check attenuators (low, mid, and high-
level) into the external audit device for a period of two times the
averaging period plus 1 minute (e.g., 13 minutes for a 6-minute
averaging period). Compare the path length corrected opacity value of
each attenuator to the valid average value calculated by the COMS data
recording device for that attenuator.
(4) Operational Test Period. Before conducting the operational
testing, you must have successfully completed the field audit tests
described in sections 8.1(3)(i) through 8.1(3)(iv). Then, you operate
the COMS for an initial 168-hour test period while the source is
operating under normal operating conditions. If normal operations
contain routine source shutdowns, include the source's down periods in
the 168-hour operational test period. However, you must ensure that the
following minimum source operating time is included in the operational
test period: (1) For a batch operation, the operational test period must
include at least one full cycle of batch operation during the 168-hour
period unless the batch operation is longer than 168 hours or (2) for
continuous operating processes, the unit must be operating for at least
50 percent of the 168-hour period. Except during times of instrument
zero and upscale calibration drift checks, you must analyze the effluent
gas for opacity and produce a permanent record of the COMS output.
During this period, you may not perform unscheduled maintenance, repair,
or adjustment to the COMS. Automatic zero and calibration adjustments
(i.e., intrinsic adjustments), made by the COMS without operator
intervention or initiation, are allowable at any time. At the end of the
operational test period, verify and record that the COMS optical
alignment is still correct. If the test period is interrupted because of
COMS failure, record the time when the failure occurred. After the
failure is corrected, you restart the 168-hour period and tests from the
beginning (0-hour). During the operational test period, perform the
following test procedures:
(i) Zero Calibration Drift Test. At the outset of the 168-hour
operational test period and at each 24-hour interval, the automatic
calibration check system must initiate the simulated zero device to
allow the zero drift to be determined. Record the COMS response to the
simulated zero device. After each 24-hour period, subtract the COMS zero
reading from the nominal value of the simulated zero device to calculate
the 24-hour zero drift (ZD). At the end of the 168-hour period,
calculate the arithmetic mean, standard deviation, and confidence
coefficient of the 24-hour ZDs using equations 1-3, 1-4, and 1-5.
Calculate the sum of the absolute value of the mean and the absolute
value of the confidence coefficient using equation 1-6, and report this
value as the 24-hour ZD error.
(ii) Upscale Calibration Drift Test. At each 24-hour interval after
the simulated zero device value has been checked, check and record the
COMS response to the upscale calibration device. After each 24-hour
period, subtract the COMS upscale reading from the nominal value of the
upscale calibration device to calculate the 24-hour calibration drift
(CD). At the end of the 168-hour period, calculate the arithmetic mean,
standard deviation, and confidence coefficient of the 24-hour CD using
equations 1-3, 1-4, and 1-5. Calculate the sum of the absolute value of
the mean and the absolute value of the confidence coefficient using
equation 1-6, and report this value as the 24-hour CD error.
(5) Retesting. If the COMS fails to meet the specifications for the
tests conducted under the operational test period, make the necessary
corrections and restart the operational test period. Depending on the
opinion of the enforcing agency, you may have to repeat some or all of
the field audit tests.
8.2 What are the responsibilities of the Opacity Monitor
Manufacturer?
You, the manufacturer, must carry out the following activities:
(1) Conduct the verification procedures for design specifications in
section 6 of ASTM D 6216-98.
(2) Conduct the verification procedures for performance
specifications in section 7 of ASTM D 6216-98.
(3) Provide to the owner or operator, a report of the opacity
monitor's conformance to the design and performance specifications
required in sections 6 and 7 of ASTM D 6216-98 in accordance with the
reporting requirements of section 9 in ASTM D 6216-98.

9.0 What quality control measures are required by PS-1?

Opacity monitor manufacturers must initiate a quality program
following the requirements of ASTM D 6216-98, section 8. The quality
program must include (1) a quality system and (2) a corrective action
program.

[[Page 607]]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure [Reserved]

12.0 What Calculations Are Needed for PS-1?

12.1 Desired Attenuator Values. Calculate the desired attenuator
value corrected to the emission outlet pathlength as follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.008

Where:

OP1=Nominal opacity value of required low-, mid-, or high-
range calibration attenuators.
OP2=Desired attenuator opacity value from ASTM D 6216-98,
section 7.5 at the opacity limit required by the applicable subpart.
L1=Monitoring pathlength.
L2=Emission outlet pathlength.
12.2 Luminous Transmittance Value of a Filter. Calculate the
luminous transmittance of a filter as follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.009

Where:

LT=Luminous transmittance
Ti=Weighted tested filter transmittance.
12.3 Arithmetic Mean. Calculate the arithmetic mean of a data set as
follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.010

Where:
[GRAPHIC] [TIFF OMITTED] TR10AU00.011

12.4 Standard Deviation. Calculate the standard deviation as
follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.012

Where:

Sd=Standard deviation of a data set.

12.5 Confidence Coefficient. Calculate the 2.5 percent error
confidence coefficient (one-tailed) as follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.013

Where:

CC=Confidence coefficient
t0.975=t - value (see table 1-2).

12.6 Calibration Error. Calculate the error (calibration error, zero
drift error, and calibration drift error) as follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.014

Where:

Er=Error.

12.7 Conversion of Opacity Values for Monitor Pathlength to Emission
Outlet Pathlength. When the monitor pathlength is different from the
emission outlet pathlength, use either of the following equations to
convert from one basis to the other (this conversion may be
automatically calculated by the monitoring system):
[GRAPHIC] [TIFF OMITTED] TR10AU00.015

[GRAPHIC] [TIFF OMITTED] TR10AU00.016

Where:

Op1=Opacity of the effluent based upon L1.
Op2=Opacity of the effluent based upon L2.
L1=Monitor pathlength.
L2=Emission outlet pathlength.
OD1=Optical density of the effluent based upon L1.
OD2=Optical density of the effluent based upon L2.

[[Page 608]]

12.8 Mean Response Wavelength. Calculate the mean of the effective
spectral response curve from the individual responses at the specified
wavelength values as follows:
[GRAPHIC] [TIFF OMITTED] TR10AU00.017

Where:

L=mean of the effective spectral response curve
Li=The specified wavelength at which the response
gi is calculated at 20 nm intervals.
gi=The individual response value at Li.

13.0 What Specifications Does a COMS Have To Meet for Certification?

A COMS must meet the following design, manufacturer's performance,
and field audit performance specifications:
13.1 Design Specifications. The opacity monitoring equipment must
comply with the design specifications of ASTM D 6216-98.
13.2 Manufacturer's Performance Specifications. The opacity monitor
must comply with the manufacturer's performance specifications of ASTM D
6216-98.
13.3 Field Audit Performance Specifications. The installed COMS must
comply with the following performance specifications:
(1) Optical Alignment. Objectively indicate proper alignment
relative to reference marks (e.g., bull's-eye) or conditions.
(2) Calibration Error. The calibration error must be <=3 percent
opacity for each of the three calibration attenuators.
(3) System Response Time. The COMS upscale and downscale response
times must be <=10 seconds as measured at the COMS data recorder.
(4) Averaging Period Calculation and Recording. The COMS data
recorder must average and record each calibration attenuator value to
within 2 percent opacity of the certified value of
the attenuator.
(5) Operational Test Period. The COMS must be able to measure and
record opacity and to perform daily calibration drift assessments for
168 hours without unscheduled maintenance, repair, or adjustment.
(6) Zero and Upscale Calibration Drift Error. The COMS zero and
upscale calibration drift error must not exceed 2 percent opacity over a
24 hour period.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Which references are relevant to this method?

1. Experimental Statistics. Department of Commerce. National Bureau
of Standards Handbook 91. Paragraph 3-3.1.4. 1963. 3-31 p.
2. Performance Specifications for Stationary Source Monitoring
Systems for Gases and Visible Emissions, EPA-650/2-74-013, January 1974,
U. S. Environmental Protection Agency, Research Triangle Park, NC.
3. Koontz, E.C., Walton, J. Quality Assurance Programs for Visible
Emission Evaluations. Tennessee Division of Air Pollution Control.
Nashville, TN. 78th Meeting of the Air Pollution Control Association.
Detroit, MI. June 16-21, 1985.
4. Evaluation of Opacity CEMS Reliability and Quality Assurance
Procedures. Volume 1. U. S. Environmental Protection Agency. Research
Triangle Park, NC. EPA-340/1-86-009a.
5. Nimeroff, I. ``Colorimetry Precision Measurement and
Calibration.'' NBS Special Publication 300. Volume 9. June 1972.
6. Technical Assistance Document: Performance Audit Procedures for
Opacity Monitors. U. S. Environmental Protection Agency. Research
Triangle Park, NC. EPA-600/8-87-025. April 1987.
7. Technical Assistance Document: Performance Audit Procedures for
Opacity Monitors. U. S. Environmental Protection Agency. Research
Triangle Park, NC. EPA-450/4-92-010. April 1992.
8. ASTM D 6216-98: Standard Practice for Opacity Monitor
Manufacturers to Certify Conformance with Design and Performance
Specifications. American Society for Testing and Materials (ASTM). April
1998.

17.0 What tables and diagrams are relevant to this method?

17.1 Reference Tables.

Table 1-1--Source C, Human Eye Response Factor
----------------------------------------------------------------------------------------------------------------
Wavelength nanometers Weighting factor \a\ Wavelength nanometers Weighting factor \a\
----------------------------------------------------------------------------------------------------------------
380.................................. 0 590 6627
390.................................. 0 600 5316
400.................................. 2 610 4176
410.................................. 9 620 3153
420.................................. 37 630 2190
430.................................. 122 640 1443
440.................................. 262 650 886
450.................................. 443 660 504

[[Page 609]]

460.................................. 694 670 259
470.................................. 1058 680 134
480.................................. 1618 690 62
490.................................. 2358 700 29
500.................................. 3401 720 14
510.................................. 4833 720 6
520.................................. 6462 730 3
530.................................. 7934 740 2
540.................................. 9194 750 1
550.................................. 9832 760 1
560.................................. 9841 770 0
570.................................. 9147 780 0
580.................................. 7992 ....................... .......................
----------------------------------------------------------------------------------------------------------------
\1\ Total of weighting factors=100,000.

Table 1-2 \T\ Values
----------------------------------------------------------------------------------------------------------------
n \a\ \t\ 0.975 n \a\ \t\ 0.975 n \a\ \t\ 0.975
----------------------------------------------------------------------------------------------------------------
2.............................................. 12.706 7 2.447 12 2.201
3.............................................. 4.303 8 2.365 13 2.179
4.............................................. 3.182 9 2.306 14 2.160
5.............................................. 2.776 10 2.262 15 2.145
6.............................................. 2.571 11 2.228 16 2.131
----------------------------------------------------------------------------------------------------------------
\a\ The values in this table are already corrected for n-1 degrees of freedom. Use n equal to the number of
individual values.

17.2 Diagrams.

[[Page 610]]

[GRAPHIC] [TIFF OMITTED] TR10AU00.018

[[Page 611]]

[GRAPHIC] [TIFF OMITTED] TR10AU00.019

[[Page 612]]

[GRAPHIC] [TIFF OMITTED] TR10AU00.020

[[Page 613]]

[GRAPHIC] [TIFF OMITTED] TR10AU00.021

[[Page 614]]

Performance Specification 2--Specifications and Test Procedures for
SO2 and NOX Continuous Emission Monitoring Systems
in Stationary Sources

1.0 Scope and Application

1.1 Analytes

------------------------------------------------------------------------
Analyte CAS Nos.
------------------------------------------------------------------------
Sulfur Dioxide (SO2)................................ 7449-09-5
Nitrogen Oxides (NOX)............................... 10102-44-0 (NO2),
10024-97-2 (NO)
------------------------------------------------------------------------

1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
SO2 and NOX continuous emission monitoring systems
(CEMS) at the time of installation or soon after and whenever specified
in the regulations. The CEMS may include, for certain stationary
sources, a diluent (O2 or CO2) monitor.
1.2.2 This specification is not designed to evaluate the installed
CEMS performance over an extended period of time nor does it identify
specific calibration techniques and other auxiliary procedures to assess
the CEMS performance. The source owner or operator is responsible to
calibrate, maintain, and operate the CEMS properly. The Administrator
may require, under Section 114 of the Act, the operator to conduct CEMS
performance evaluations at other times besides the initial test to
evaluate the CEMS performance. See 40 CFR Part 60, Sec. 60.13(c).

2.0 Summary of Performance Specification

Procedures for measuring CEMS relative accuracy and calibration
drift are outlined. CEMS installation and measurement location
specifications, equipment specifications, performance specifications,
and data reduction procedures are included. Conformance of the CEMS with
the Performance Specification is determined.

3.0 Definitions

3.1 Calibration Drift (CD) means the difference in the CEMS output
readings from the established reference value after a stated period of
operation during which no unscheduled maintenance, repair, or adjustment
took place.
3.2 Centroidal Area means a concentric area that is geometrically
similar to the stack or duct cross section and is no greater than l
percent of the stack or duct cross-sectional area.
3.3 Continuous Emission Monitoring System means the total equipment
required for the determination of a gas concentration or emission rate.
The sample interface, pollutant analyzer, diluent analyzer, and data
recorder are the major subsystems of the CEMS.
3.4 Data Recorder means that portion of the CEMS that provides a
permanent record of the analyzer output. The data recorder may include
automatic data reduction capabilities.
3.5 Diluent Analyzer means that portion of the CEMS that senses the
diluent gas (i.e., CO2 or O2) and generates an
output proportional to the gas concentration.
3.6 Path CEMS means a CEMS that measures the gas concentration along
a path greater than 10 percent of the equivalent diameter of the stack
or duct cross section.
3.7 Point CEMS means a CEMS that measures the gas concentration
either at a single point or along a path equal to or less than 10
percent of the equivalent diameter of the stack or duct cross section.
3.8 Pollutant Analyzer means that portion of the CEMS that senses
the pollutant gas and generates an output proportional to the gas
concentration.
3.9 Relative Accuracy (RA) means the absolute mean difference
between the gas concentration or emission rate determined by the CEMS
and the value determined by the reference method (RM), plus the 2.5
percent error confidence coefficient of a series of tests, divided by
the mean of the RM tests or the applicable emission limit.
3.10 Sample Interface means that portion of the CEMS used for one or
more of the following: sample acquisition, sample delivery, sample
conditioning, or protection of the monitor from the effects of the stack
effluent.
3.11 Span Value means the concentration specified for the affected
source category in an applicable subpart of the regulations that is used
to set the calibration gas concentration and in determining calibration
drift.

4.0 Interferences [Reserved]

5.0 Safety

The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This performance
specification may not address all of the safety problems associated with
these procedures. It is the responsibility of the user to establish
appropriate safety and health practices and determine the applicable
regulatory limitations prior to performing these procedures. The CEMS
user's manual and materials recommended by the reference method should
be consulted for specific precautions to be taken.

6.0 Equipment and Supplies

6.1 CEMS Equipment Specifications.
6.1.1 Data Recorder Scale. The CEMS data recorder output range must
include zero and a high-level value. The high-level value is chosen by
the source owner or operator and is defined as follows:
6.1.1.1 For a CEMS intended to measure an uncontrolled emission
(e.g., SO2 measurements at the inlet of a flue gas

[[Page 615]]

desulfurization unit), the high-level value should be between 1.25 and 2
times the maximum potential emission level over the appropriate
averaging time, unless otherwise specified in an applicable subpart of
the regulations.
6.1.1.2 For a CEMS installed to measure controlled emissions or
emissions that are in compliance with an applicable regulation, the
high-level value between 1.5 times the pollutant concentration
corresponding to the emission standard level and the span value given in
the applicable regulations is adequate.
6.1.1.3 Alternative high-level values may be used, provided the
source can measure emissions which exceed the full-scale limit in
accordance with the requirements of applicable regulations.
6.1.1.4 If an analog data recorder is used, the data recorder output
must be established so that the high-level value would read between 90
and 100 percent of the data recorder full scale. (This scale requirement
may not be applicable to digital data recorders.) The zero and high
level calibration gas, optical filter, or cell values should be used to
establish the data recorder scale.
6.1.2 The CEMS design should also allow the determination of
calibration drift at the zero and high-level values. If this is not
possible or practical, the design must allow these determinations to be
conducted at a low-level value (zero to 20 percent of the high-level
value) and at a value between 50 and 100 percent of the high-level
value. In special cases, the Administrator may approve a single-point
calibration-drift determination.
6.2 Other equipment and supplies, as needed by the applicable
reference method(s) (see Section 8.4.2 of this Performance
Specification), may be required.

7.0 Reagents and Standards

7.1 Reference Gases, Gas Cells, or Optical Filters. As specified by
the CEMS manufacturer for calibration of the CEMS (these need not be
certified).
7.2 Reagents and Standards. May be required as needed by the
applicable reference method(s) (see Section 8.4.2 of this Performance
Specification).

8.0 Performance Specification Test Procedure

8.1 Installation and Measurement Location Specifications.
8.1.1 CEMS Installation. Install the CEMS at an accessible location
where the pollutant concentration or emission rate measurements are
directly representative or can be corrected so as to be representative
of the total emissions from the affected facility or at the measurement
location cross section. Then select representative measurement points or
paths for monitoring in locations that the CEMS will pass the RA test
(see Section 8.4). If the cause of failure to meet the RA test is
determined to be the measurement location and a satisfactory correction
technique cannot be established, the Administrator may require the CEMS
to be relocated. Suggested measurement locations and points or paths
that are most likely to provide data that will meet the RA requirements
are listed below.
8.1.2 CEMS Measurement Location. It is suggested that the
measurement location be (1) at least two equivalent diameters downstream
from the nearest control device, the point of pollutant generation, or
other point at which a change in the pollutant concentration or emission
rate may occur and (2) at least a half equivalent diameter upstream from
the effluent exhaust or control device.
8.1.2.1 Point CEMS. It is suggested that the measurement point be
(1) no less than 1.0 meter (3.3 ft) from the stack or duct wall or (2)
within or centrally located over the centroidal area of the stack or
duct cross section.
8.1.2.2 Path CEMS. It is suggested that the effective measurement
path (1) be totally within the inner area bounded by a line 1.0 meter
(3.3 ft) from the stack or duct wall, or (2) have at least 70 percent of
the path within the inner 50 percent of the stack or duct cross-
sectional area, or (3) be centrally located over any part of the
centroidal area.
8.1.3 Reference Method Measurement Location and Traverse Points.
8.1.3.1 Select, as appropriate, an accessible RM measurement point
at least two equivalent diameters downstream from the nearest control
device, the point of pollutant generation, or other point at which a
change in the pollutant concentration or emission rate may occur, and at
least a half equivalent diameter upstream from the effluent exhaust or
control device. When pollutant concentration changes are due solely to
diluent leakage (e.g., air heater leakages) and pollutants and diluents
are simultaneously measured at the same location, a half diameter may be
used in lieu of two equivalent diameters. The CEMS and RM locations need
not be the same.
8.1.3.2 Select traverse points that assure acquisition of
representative samples over the stack or duct cross section. The minimum
requirements are as follows: Establish a ``measurement line'' that
passes through the centroidal area and in the direction of any expected
stratification. If this line interferes with the CEMS measurements,
displace the line up to 30 cm (12 in.) (or 5 percent of the equivalent
diameter of the cross section, whichever is less) from the centroidal
area. Locate three traverse points at 16.7, 50.0, and 83.3 percent of
the measurement line. If the measurement line is longer than 2.4 meters

[[Page 616]]

(7.8 ft) and pollutant stratification is not expected, the three
traverse points may be located on the line at 0.4, 1.2, and 2.0 meters
from the stack or duct wall. This option must not be used after wet
scrubbers or at points where two streams with different pollutant
concentrations are combined. If stratification is suspected, the
following procedure is suggested. For rectangular ducts, locate at least
nine sample points in the cross section such that sample points are the
centroids of similarly-shaped, equal area divisions of the cross
section. Measure the pollutant concentration, and, if applicable, the
diluent concentration at each point using appropriate reference methods
or other appropriate instrument methods that give responses relative to
pollutant concentrations. Then calculate the mean value for all sample
points. For circular ducts, conduct a 12-point traverse (i.e., six
points on each of the two perpendicular diameters) locating the sample
points as described in 40 CFR 60, Appendix A, Method 1. Perform the
measurements and calculations as described above. Determine if the mean
pollutant concentration is more than 10% different from any single
point. If so, the cross section is considered to be stratified, and the
tester may not use the alternative traverse point locations (...0.4,
1.2, and 2.0 meters from the stack or duct wall.) but must use the three
traverse points at 16.7, 50.0, and 83.3 percent of the entire
measurement line. Other traverse points may be selected, provided that
they can be shown to the satisfaction of the Administrator to provide a
representative sample over the stack or duct cross section. Conduct all
necessary RM tests within 3 cm (1.2 in.) of the traverse points, but no
closer than 3 cm (1.2 in.) to the stack or duct wall.
8.2 Pretest Preparation. Install the CEMS, prepare the RM test site
according to the specifications in Section 8.1, and prepare the CEMS for
operation according to the manufacturer's written instructions.
8.3 Calibration Drift Test Procedure.
8.3.1 CD Test Period. While the affected facility is operating at
more than 50 percent of normal load, or as specified in an applicable
subpart, determine the magnitude of the CD once each day (at 24-hour
intervals) for 7 consecutive days according to the procedure given in
Sections 8.3.2 through 8.3.4.
8.3.2 The purpose of the CD measurement is to verify the ability of
the CEMS to conform to the established CEMS calibration used for
determining the emission concentration or emission rate. Therefore, if
periodic automatic or manual adjustments are made to the CEMS zero and
calibration settings, conduct the CD test immediately before these
adjustments, or conduct it in such a way that the CD can be determined.
8.3.3 Conduct the CD test at the two points specified in Section
6.1.2. Introduce to the CEMS the reference gases, gas cells, or optical
filters (these need not be certified). Record the CEMS response and
subtract this value from the reference value (see example data sheet in
Figure 2-1).
8.4 Relative Accuracy Test Procedure.
8.4.1 RA Test Period. Conduct the RA test according to the procedure
given in Sections 8.4.2 through 8.4.6 while the affected facility is
operating at more than 50 percent of normal load, or as specified in an
applicable subpart. The RA test may be conducted during the CD test
period.
8.4.2 Reference Methods. Unless otherwise specified in an applicable
subpart of the regulations, Methods 3B, 4, 6, and 7, or their approved
alternatives, are the reference methods for diluent (O2 and
CO2), moisture, SO2, and NOX,
respectively.
8.4.3 Sampling Strategy for RM Tests. Conduct the RM tests in such a
way that they will yield results representative of the emissions from
the source and can be correlated to the CEMS data. It is preferable to
conduct the diluent (if applicable), moisture (if needed), and pollutant
measurements simultaneously. However, diluent and moisture measurements
that are taken within an hour of the pollutant measurements may be used
to calculate dry pollutant concentration and emission rates. In order to
correlate the CEMS and RM data properly, note the beginning and end of
each RM test period of each run (including the exact time of day) on the
CEMS chart recordings or other permanent record of output. Use the
following strategies for the RM tests:
8.4.3.1 For integrated samples (e.g., Methods 6 and Method 4), make
a sample traverse of at least 21 minutes, sampling for an equal time at
each traverse point (see Section 8.1.3.2 for discussion of traverse
points.
8.4.3.2 For grab samples (e.g., Method 7), take one sample at each
traverse point, scheduling the grab samples so that they are taken
simultaneously (within a 3-minute period) or at an equal interval of
time apart over the span of time the CEM pollutant is measured. A test
run for grab samples must be made up of at least three separate
measurements.

Note: At times, CEMS RA tests are conducted during new source
performance standards performance tests. In these cases, RM results
obtained during CEMS RA tests may be used to determine compliance as
long as the source and test conditions are consistent with the
applicable regulations.

8.4.4 Number of RM Tests. Conduct a minimum of nine sets of all
necessary RM test runs.

Note: More than nine sets of RM tests may be performed. If this
option is chosen, a maximum of three sets of the test results may be
rejected so long as the total number of test results used to determine
the RA is greater than or equal to nine. However, all data

[[Page 617]]

must be reported, including the rejected data.

8.4.5 Correlation of RM and CEMS Data. Correlate the CEMS and the RM
test data as to the time and duration by first determining from the CEMS
final output (the one used for reporting) the integrated average
pollutant concentration or emission rate for each pollutant RM test
period. Consider system response time, if important, and confirm that
the pair of results are on a consistent moisture, temperature, and
diluent concentration basis. Then, compare each integrated CEMS value
against the corresponding average RM value. Use the following guidelines
to make these comparisons.
8.4.5.1 If the RM has an integrated sampling technique, make a
direct comparison of the RM results and CEMS integrated average value.
8.4.5.2 If the RM has a grab sampling technique, first average the
results from all grab samples taken during the test run, and then
compare this average value against the integrated value obtained from
the CEMS chart recording or output during the run. If the pollutant
concentration is varying with time over the run, the arithmetic average
of the CEMS value recorded at the time of each grab sample may be used.
8.4.6 Calculate the mean difference between the RM and CEMS values
in the units of the emission standard, the standard deviation, the
confidence coefficient, and the relative accuracy according to the
procedures in Section 12.0.
8.5 Reporting. At a minimum (check with the appropriate regional
office, State, or Local agency for additional requirements, if any),
summarize in tabular form the results of the CD tests and the RA tests
or alternative RA procedure, as appropriate. Include all data sheets,
calculations, charts (records of CEMS responses), cylinder gas
concentration certifications, and calibration cell response
certifications (if applicable) necessary to confirm that the performance
of the CEMS met the performance specifications.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Sample collection and analysis are concurrent for this Performance
Specification (see Section 8.0). Refer to the RM for specific analytical
procedures.

12.0 Calculations and Data Analysis

Summarize the results on a data sheet similar to that shown in
Figure 2-2 (in Section 18.0).
12.1 All data from the RM and CEMS must be on a consistent dry basis
and, as applicable, on a consistent diluent basis and in the units of
the emission standard. Correct the RM and CEMS data for moisture and
diluent as follows:
12.1.1 Moisture Correction (as applicable). Correct each wet RM run
for moisture with the corresponding Method 4 data; correct each wet CEMS
run using the corresponding CEMS moisture monitor date using Equation 2-
1.
[GRAPHIC] [TIFF OMITTED] TR17OC00.453

12.1.2 Correction to Units of Standard (as applicable). Correct each
dry RM run to the units of the emission standard with the corresponding
Method 3B data; correct each dry CEMS run using the corresponding CEMS
diluent monitor data as follows:
12.1.2.1 Correct to Diluent Basis. The following is an example of
concentration (ppm) correction to 7% oxygen.
[GRAPHIC] [TIFF OMITTED] TR17OC00.454

The following is an example of mass/gross calorific value (lbs/
million Btu) correction.

lbs/MMBtu=Conc(dry) (F-factor) (20.9/20.9-%02)

12.2 Arithmetic Mean. Calculate the arithmetic mean of the
difference, d, of a data set as follows:

[[Page 618]]

[GRAPHIC] [TIFF OMITTED] TR17OC00.455

Where:

n=Number of data points.
[GRAPHIC] [TIFF OMITTED] TR17OC00.456

12.3 Standard Deviation. Calculate the standard deviation,
Sd, as follows:
[GRAPHIC] [TIFF OMITTED] TR17OC00.457

12.4 Confidence Coefficient. Calculate the 2.5 percent error
confidence coefficient (one-tailed), CC, as follows:
[GRAPHIC] [TIFF OMITTED] TR17OC00.458

Where:

t0.975=t-value (see Table 2-1).

12.5 Relative Accuracy. Calculate the RA of a set of data as
follows:
[GRAPHIC] [TIFF OMITTED] TR17OC00.459

Where:

[verbar]d[verbar]=Absolute value of the mean differences (from Equation
2-3).
[verbar]CC[verbar]=Absolute value of the confidence coefficient (from
Equation 2-3).
RM=Average RM value. In cases where the average emissions for the test
are less than 50 percent of the applicable standard, substitute the
emission standard value in the denominator of Eq. 2-6 in place of RM. In
all other cases, use RM.

13.0 Method Performance

13.1 Calibration Drift Performance Specification. The CEMS
calibration must not drift or deviate from the reference value of the
gas cylinder, gas cell, or optical filter by more than 2.5 percent of
the span value. If the CEMS includes pollutant and diluent monitors, the
CD must be determined separately for each in terms of concentrations
(See Performance Specification 3 for the diluent specifications), and
none of the CDs may exceed the specification.
13.2 Relative Accuracy Performance Specification. The RA of the CEMS
must be no greater than 20 percent when RM is used in the denominator of
Eq. 2-6 (average emissions during test are greater than 50 percent of
the emission standard) or 10 percent when the applicable emission
standard is used in the denominator of Eq. 2-6 (average emissions during
test are less than 50 percent of the emission standard).
13.3 For instruments that use common components to measure more than
one effluent gas constituent, all channels must simultaneously pass the
RA requirement, unless it can be demonstrated that any adjustments made
to one channel did not affect the others.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Alternative Procedures

Paragraphs 60.13(j)(1) and (2) of 40 CFR part 60 contain criteria
for which the reference method procedure for determining relative
accuracy (see Section 8.4 of this Performance Specification) may be
waived and the following procedure substituted.
16.1 Conduct a complete CEMS status check following the
manufacturer's written instructions. The check should include operation
of the light source, signal receiver, timing mechanism functions, data
acquisition and data reduction functions, data recorders, mechanically
operated functions (mirror movements, zero pipe operation, calibration
gas valve operations, etc.), sample filters, sample line heaters,
moisture traps, and other related functions of the CEMS, as applicable.
All parts of the CEMS shall be functioning properly before proceeding to
the alternative RA procedure.
16.2 Alternative RA Procedure.
16.2.1 Challenge each monitor (both pollutant and diluent, if
applicable) with cylinder gases of known concentrations or calibration
cells that produce known responses at two measurement points within the
ranges shown in Table 2-2 (Section 18).

[[Page 619]]

16.2.2 Use a separate cylinder gas (for point CEMS only) or
calibration cell (for path CEMS or where compressed gas cylinders can
not be used) for measurement points 1 and 2. Challenge the CEMS and
record the responses three times at each measurement point. The
Administrator may allow dilution of cylinder gas using the performance
criteria in Test Method 205, 40 CFR Part 51, Appendix M. Use the average
of the three responses in determining relative accuracy.
16.2.3 Operate each monitor in its normal sampling mode as nearly as
possible. When using cylinder gases, pass the cylinder gas through all
filters, scrubbers, conditioners, and other monitor components used
during normal sampling and as much of the sampling probe as practical.
When using calibration cells, the CEMS components used in the normal
sampling mode should not be by-passed during the RA determination. These
include light sources, lenses, detectors, and reference cells. The CEMS
should be challenged at each measurement point for a sufficient period
of time to assure adsorption-desorption reactions on the CEMS surfaces
have stabilized.
16.2.4 Use cylinder gases that have been certified by comparison to
National Institute of Standards and Technology (NIST) gaseous standard
reference material (SRM) or NIST/EPA approved gas manufacturer's
certified reference material (CRM) (See Reference 2 in Section 17.0)
following EPA Traceability Protocol Number 1 (See Reference 3 in Section
17.0). As an alternative to Protocol Number 1 gases, CRM's may be used
directly as alternative RA cylinder gases. A list of gas manufacturers
that have prepared approved CRM's is available from EPA at the address
shown in Reference 2. Procedures for preparation of CRM's are described
in Reference 2.
16.2.5 Use calibration cells certified by the manufacturer to
produce a known response in the CEMS. The cell certification procedure
shall include determination of CEMS response produced by the calibration
cell in direct comparison with measurement of gases of known
concentration. This can be accomplished using SRM or CRM gases in a
laboratory source simulator or through extended tests using reference
methods at the CEMS location in the exhaust stack. These procedures are
discussed in Reference 4 in Section 17.0. The calibration cell
certification procedure is subject to approval of the Administrator.
16.3 The differences between the known concentrations of the
cylinder gases and the concentrations indicated by the CEMS are used to
assess the accuracy of the CEMS. The calculations and limits of
acceptable relative accuracy are as follows:
16.3.1 For pollutant CEMS:
[GRAPHIC] [TIFF OMITTED] TR17OC00.460

Where:

d=Average difference between responses and the concentration/responses
(see Section 16.2.2).
AC=The known concentration/response of the cylinder gas or calibration
cell.

16.3.2 For diluent CEMS:

RA=[verbar]d[verbar] <= O.7 percent O2 or CO2, as
applicable.

Note: Waiver of the relative accuracy test in favor of the
alternative RA procedure does not preclude the requirements to complete
the CD tests nor any other requirements specified in an applicable
subpart for reporting CEMS data and performing CEMS drift checks or
audits.

17.0 References

1. Department of Commerce. Experimental Statistics. Handbook 91.
Washington, D.C. p. 3-31, paragraphs 3-3.1.4.
2. ``A Procedure for Establishing Traceability of Gas Mixtures to
Certain National Bureau of Standards Standard Reference Materials.''
Joint publication by NBS and EPA. EPA 600/7-81-010. Available from U.S.
Environmental Protection Agency, Quality Assurance Division (MD-77),
Research Triangle Park, North Carolina 27711.
3. ``Traceability Protocol for Establishing True Concentrations of
Gases Used for Calibration and Audits of Continuous Source Emission
Monitors. (Protocol Number 1).'' June 1978. Protocol Number 1 is
included in the Quality Assurance Handbook for Air Pollution Measurement
Systems, Volume III, Stationary Source Specific Methods. EPA-600/4-77-
027b. August 1977.
4. ``Gaseous Continuous Emission Monitoring Systems--Performance
Specification Guidelines for SO2, NOX,
CO2, O2, and TRS.'' EPA-450/3-82-026. Available
from the U.S.

[[Page 620]]

EPA, Emission Measurement Center, Emission Monitoring and Data Analysis
Division (MD-19), Research Triangle Park, North Carolina 27711.

18.0 Tables, Diagrams, Flowcharts, and Validation Data

Figure 2-1. Calibration Drift Determination

Table 2-1--t-Values
----------------------------------------------------------------------------------------------------------------
na t0.975 na t0.975 na t0.975
----------------------------------------------------------------------------------------------------------------
2.............................................. 12.706 7 2.447 12 2.201
3.............................................. 4.303 8 2.365 13 2.179
4.............................................. 3.182 9 2.306 14 2.160
5.............................................. 2.776 10 2.262 15 2.145
6.............................................. 2.571 11 2.228 16 2.131
----------------------------------------------------------------------------------------------------------------
a The values in this table are already corrected for n-1 degrees of freedom. Use n equal to the number of
individual values.

Table 2-2--Measurement Range
----------------------------------------------------------------------------------------------------------------
Diluent monitor for
Measurement point Pollutant monitor -------------------------------------------------
CO2 O2
----------------------------------------------------------------------------------------------------------------
1.................................... 20-30% of span value... 5-8% by volume......... 4-6% by volume.
2.................................... 50-60% of span value... 10-14% by volume....... 8-12% by volume.

--------------------------------------------------------------------------------------------------------------------------------------------------------
Calibration value Percent of span value (C-
Day Date and time (C) Monitor value (M) Difference (C-M) M)/span value x 100
--------------------------------------------------------------------------------------------------------------------------------------------------------
Low-level....................... .......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
High-level...................... .......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
.......... ............... ................... ................... ................... ..........................
--------------------------------------------------------------------------------------------------------------------------------------------------------

Figure 2-2. Relative Accuracy Determination.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SO2 NOXb CO2 or O2a SO2a NOXa
Run No. Date and time ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
RM CEMS Diff RM CEMS Diff RM CEMS RM CEMS Diff RM CEMS Diff
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
ppmc
ppmc %c %c mass/GCV
mass/GCV
-------------------------------
1.............................
-------------------------------
2.............................
-------------------------------
3.............................
-------------------------------
4.............................
-------------------------------
5.............................
-------------------------------
6.............................
-------------------------------
7.............................
-------------------------------
8.............................
-------------------------------
9.............................
-------------------------------
10............................
-------------------------------
11............................
-------------------------------
12............................
-------------------------------

[[Page 621]]

Average
Confidence Interval
Accuracy
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
a For steam generators.
b Average of three samples.
c Make sure that RM and CEMS data are on a consistent basis, either wet or dry.

Performance Specification 3--Specifications and Test Procedures for
O2 and CO2 Continuous Emission Monitoring Systems
in Stationary Sources

1.0 Scope and Application

1.1 Analytes.

------------------------------------------------------------------------
Analytes CAS No.
------------------------------------------------------------------------
Carbon Dioxide (CO2).................................... 124-38-9
Oxygen (O2)............................................. 7782-44-7
------------------------------------------------------------------------

1.2 Applicability.
1.2.1 This specification is for evaluating acceptability of
O2 and CO2 continuous emission monitoring systems
(CEMS) at the time of installation or soon after and whenever specified
in an applicable subpart of the regulations. This specification applies
to O2 or CO2 monitors that are not included under
Performance Specification 2 (PS 2).
1.2.2 This specification is not designed to evaluate the installed
CEMS performance over an extended period of time, nor does it identify
specific calibration techniques and other auxiliary procedures to assess
the CEMS performance. The source owner or operator, is responsible to
calibrate, maintain, and operate the CEMS properly. The Administrator
may require, under Section 114 of the Act, the operator to conduct CEMS
performance evaluations at other times besides the initial test to
evaluate the CEMS performance. See 40 CFR part 60, Section 60.13(c).
1.2.3 The definitions, installation and measurement location
specifications, calculations and data analysis, and references are the
same as in PS 2, Sections 3, 8.1, 12, and 17, respectively, and also
apply to O2 and CO2 CEMS under this specification.
The performance and equipment specifications and the relative accuracy
(RA) test procedures for O2 and CO2 CEMS do not
differ from those for SO2 and NOX CEMS (see PS 2),
except as noted below.

2.0 Summary of Performance Specification

The RA and calibration drift (CD) tests are conducted to determine
conformance of the CEMS to the specification.

3.0 Definitions

Same as in Section 3.0 of PS 2.

4.0 Interferences [Reserved]

5.0 Safety

This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and health
practices and determine the applicable regulatory limitations prior to
performing this performance specification. The CEMS users manual should
be consulted for specific precautions to be taken with regard to the
analytical procedures.

6.0 Equipment and Supplies

Same as Section 6.0 of PS2.

7.0 Reagents and Standards

Same as Section 7.0 of PS2.

8.0 Sample Collection, Preservation, Storage, and Transport

8.1 Relative Accuracy Test Procedure. Sampling Strategy for
reference method (RM) Tests, Correlation of RM and CEMS Data, and Number
of RM Tests. Same as PS 2, Sections 8.4.3, 8.4.5, and 8.4.4,
respectively.
8.2 Reference Method. Unless otherwise specified in an applicable
subpart of the regulations, Method 3B or other approved alternative is
the RM for O2 or CO2.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Sample collection and analyses are concurrent for this performance
specification (see Section 8). Refer to the RM for specific analytical
procedures.

12.0 Calculations and Data Analysis

Summarize the results on a data sheet similar to that shown in
Figure 2.2 of PS2. Calculate the arithmetic difference between

[[Page 622]]

the RM and the CEMS output for each run. The average difference of the
nine (or more) data sets constitute the RA.

13.0 Method Performance

13.1 Calibration Drift Performance Specification. The CEMS
calibration must not drift by more than 0.5 percent O2 or
CO2 from the reference value of the gas, gas cell, or optical
filter.
13.2 CEMS Relative Accuracy Performance Specification. The RA of the
CEMS must be no greater than 1.0 percent O2 or
CO2.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 References

Same as in Section 17.0 of PS 2.

17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]

Performance Specification 4--Specifications and Test Procedures for
Carbon Monoxide Continuous Emission Monitoring Systems in Stationary
Sources

1.0 Scope and Application

1.1 Analytes.

------------------------------------------------------------------------
Analyte CAS No.
------------------------------------------------------------------------
Carbon Monoxide (CO)................................... 630-08-0
------------------------------------------------------------------------

1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
carbon monoxide (CO) continuous emission monitoring systems (CEMS) at
the time of installation or soon after and whenever specified in an
applicable subpart of the regulations. This specification was developed
primarily for CEMS having span values of 1,000 ppmv CO.
1.2.2 This specification is not designed to evaluate the installed
CEMS performance over an extended period of time nor does it identify
specific calibration techniques and other auxiliary procedures to assess
CEMS performance. The source owner or operator, is responsible to
calibrate, maintain, and operate the CEMS. The Administrator may
require, under Section 114 of the Act, the source owner or operator to
conduct CEMS performance evaluations at other times besides the initial
test to evaluate the CEMS performance. See 40 CFR part 60, Section
60.13(c).
1.2.3 The definitions, performance specification test procedures,
calculations, and data analysis procedures for determining calibration
drift (CD) and relative accuracy (RA) of Performance Specification 2 (PS
2), Sections 3, 8.0, and 12, respectively, apply to this specification.

2.0 Summary of Performance Specification

The CD and RA tests are conducted to determine conformance of the
CEMS to the specification.

3.0 Definitions

Same as in Section 3.0 of PS 2.

4.0 Interferences [Reserved]

5.0 Safety

6.0 Equipment and Supplies

Same as Section 6.0 of PS 2.

7.0 Reagents and Standards

Same as Section 7.0 of PS 2.

8.0 Sample Collection, Preservation, Storage, and Transport

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Sample collection and analysis are concurrent for this performance
specification (see Section 8.0). Refer to the RM for specific analytical
procedures.

12.0 Calculations and Data Analysis

Same as Section 12.0 of PS 2.

13.0 Method Performance

13.1 Calibration Drift. The CEMS calibration must not drift or
deviate from the reference value of the calibration gas, gas cell,

[[Page 623]]

or optical filter by more than 5 percent of the established span value
for 6 out of 7 test days (e.g., the established span value is 1000 ppm
for Subpart J affected facilities).
13.2 Relative Accuracy. The RA of the CEMS must be no greater than
10 percent when the average RM value is used to calculate RA or 5
percent when the applicable emission standard is used to calculate RA.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Alternative Procedures [Reserved]

17.0 References

1. Ferguson, B.B., R.E. Lester, and W.J. Mitchell. Field Evaluation
of Carbon Monoxide and Hydrogen Sulfide Continuous Emission Monitors at
an Oil Refinery. U.S. Environmental Protection Agency. Research Triangle
Park, N.C. Publication No. EPA-600/4-82-054. August 1982. 100 p.
2. ``Gaseous Continuous Emission Monitoring Systems--Performance
Specification Guidelines for SO2, NOX,
CO2, O2, and TRS.'' EPA-450/3-82-026. U.S.
Environmental Protection Agency, Technical Support Division (MD-19),
Research Triangle Park, NC 27711.
3. Repp, M. Evaluation of Continuous Monitors for Carbon Monoxide in
Stationary Sources. U.S. Environmental Protection Agency. Research
Triangle Park, N.C. Publication No. EPA-600/2-77-063. March 1977. 155 p.
4. Smith, F., D.E. Wagoner, and R.P. Donovan. Guidelines for
Development of a Quality Assurance Program: Volume VIII--Determination
of CO Emissions from Stationary Sources by NDIR Spectrometry. U.S.
Environmental Protection Agency. Research Triangle Park, N.C.
Publication No. EPA-650/4-74-005-h. February 1975. 96 p.

18.0 Tables, Diagrams, Flowcharts, and Validation Data

Same as Section 18.0 of PS 2.

Performance Specification 4A--Specifications and Test Procedures for
Carbon Monoxide Continuous Emission Monitoring Systems in Stationary
Sources

1.0 Scope and Application

1.1 Analytes.

------------------------------------------------------------------------
Analyte CAS No.
------------------------------------------------------------------------
Carbon Monoxide (CO)................................... 630-80-0
------------------------------------------------------------------------

1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
carbon monoxide (CO) continuous emission monitoring systems (CEMS) at
the time of installation or soon after and whenever specified in an
applicable subpart of the regulations. This specification was developed
primarily for CEMS that comply with low emission standards (less than
200 ppmv).
1.2.2 This specification is not designed to evaluate the installed
CEMS performance over an extended period of time nor does it identify
specific calibration techniques and other auxiliary procedures to assess
CEMS performance. The source owner or operator is responsible to
calibrate, maintain, and operate the CEMS. The Administrator may
require, under Section 114 of the Act, the source owner or operator to
conduct CEMS performance evaluations at other times besides the initial
test to evaluate CEMS performance. See 40 CFR Part 60, Section 60.13(c).
1.2.3 The definitions, performance specification, test procedures,
calculations and data analysis procedures for determining calibration
drifts (CD) and relative accuracy (RA), of Performance Specification 2
(PS 2), Sections 3, 8.0, and 12, respectively, apply to this
specification.

2.0 Summary of Performance Specification

The CD and RA tests are conducted to determine conformance of the
CEMS to the specification.

3.0 Definitions

Same as in Section 3.0 of PS 2.

4.0 Interferences [Reserved]

5.0 Safety

6.0 Equipment and Supplies

Same as Section 6.0 of PS 2 with the following additions.
6.1 Data Recorder Scale.
6.1.1 This specification is the same as Section 6.1 of PS 2. The
CEMS shall be capable of measuring emission levels under normal
conditions and under periods of short-duration peaks of high
concentrations. This dual-range capability may be met using two separate
analyzers (one for each range) or by using dual-range units which have
the capability of measuring both levels with a single unit. In the
latter case, when the reading goes above the full-scale measurement
value of the lower range, the higher-range operation shall be started
automatically. The

[[Page 624]]

CEMS recorder range must include zero and a high-level value. Under
applications of consistent low emissions, a single-range analyzer is
allowed provided normal and spike emissions can be quantified. In this
case, set an appropriate high-level value to include all emissions.
6.1.2 For the low-range scale of dual-range units, the high-level
value shall be between 1.5 times the pollutant concentration
corresponding to the emission standard level and the span value. For the
high-range scale, the high-level value shall be set at 2000 ppm, as a
minimum, and the range shall include the level of the span value. There
shall be no concentration gap between the low-and high-range scales.

7.0 Reagents and Standards

Same as Section 7.0 of PS 2.

8.0 Sample Collection, Preservation, Storage, and Transport

8.1 Relative Accuracy Test Procedure. Sampling Strategy for
reference method (RM) Tests, Number of RM Tests, and Correlation of RM
and CEMS Data are the same as PS 2, Sections 8.4.3, 8.4.4, and 8.4.5,
respectively.
8.2 Reference Methods. Unless otherwise specified in an applicable
subpart of the regulation, Methods 10, 10A, 10B, or other approved
alternative is the RM for this PS. When evaluating nondispersive
infrared CEMS using Method 10 as the RM, the alternative interference
trap specified in Section 16.0 of Method 10 shall be used.
8.3 Response Time Test Procedure. The response time test applies to
all types of CEMS, but will generally have significance only for
extractive systems.
8.3.1 Introduce zero gas into the analyzer. When the system output
has stabilized (no change greater than 1 percent of full scale for 30
sec), introduce an upscale calibration gas and wait for a stable value.
Record the time (upscale response time) required to reach 95 percent of
the final stable value. Next, reintroduce the zero gas and wait for a
stable reading before recording the response time (downscale response
time). Repeat the entire procedure three times and determine the mean
upscale and downscale response times. The slower or longer of the two
means is the system response time.
8.4 Interference Check. The CEMS must be shown to be free from the
effects of any interferences.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Sample collection and analysis are concurrent for this performance
specification (see Section 8.0). Refer to the RM for specific analytical
procedures.

12.0 Calculations and Data Analysis. Same as Section 12.0 of PS 2

13.0 Method Performance

13.1 Calibration Drift. The CEMS calibration must not drift or
deviate from the reference value of the calibration gas, gas cell, or
optical filter by more than 5 percent of the established span value for
6 out of 7 test days.
13.2 Relative Accuracy. The RA of the CEMS must be no greater than
10 percent when the average RM value is used to calculate RA, 5 percent
when the applicable emission standard is used to calculate RA, or within
5 ppmv when the RA is calculated as the absolute average difference
between the RM and CEMS plus the 2.5 percent confidence coefficient.
13.3 Response Time. The CEMS response time shall not exceed 1.5 min
to achieve 95 percent of the final stable value.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Alternative Procedures

16.1 Under conditions where the average CO emissions are less than
10 percent of the standard and this is verified by Method 10, a cylinder
gas audit may be performed in place of the RA test to determine
compliance with these limits. In this case, the cylinder gas shall
contain CO in 12 percent carbon dioxide as an interference check. If
this option is exercised, Method 10 must be used to verify that emission
levels are less than 10 percent of the standard.

17.0 References

Same as Section 17 of PS 4.

18.0 Tables, Diagrams, Flowcharts, and Validation Data

Same as Section 18.0 of PS 2.

Performance Specification 4B--Specifications and Test Procedures for
Carbon Monoxide and Oxygen Continuous Monitoring Systems in Stationary
Sources

a. Applicability and Principle

1.1 Applicability. a. This specification is to be used for
evaluating the acceptability of carbon monoxide (CO) and oxygen
(O2) continuous emission monitoring systems (CEMS) at the
time of or soon after installation and whenever specified in the
regulations. The CEMS may include, for certain stationary sources, (a)
flow monitoring equipment to allow measurement of the dry volume of
stack effluent sampled, and (b) an automatic sampling system.

[[Page 625]]

b. This specification is not designed to evaluate the installed
CEMS' performance over an extended period of time nor does it identify
specific calibration techniques and auxiliary procedures to assess the
CEMS' performance. The source owner or operator, however, is responsible
to properly calibrate, maintain, and operate the CEMS. To evaluate the
CEMS' performance, the Administrator may require, under section 114 of
the Act, the operator to conduct CEMS performance evaluations at times
other than the initial test.
c. The definitions, installation and measurement location
specifications, test procedures, data reduction procedures, reporting
requirements, and bibliography are the same as in PS 3 (for
O2) and PS 4A (for CO) except as otherwise noted below.
1.2 Principle. Installation and measurement location specifications,
performance specifications, test procedures, and data reduction
procedures are included in this specification. Reference method tests,
calibration error tests, calibration drift tests, and interferant tests
are conducted to determine conformance of the CEMS with the
specification.

b. Definitions

2.1 Continuous Emission Monitoring System (CEMS). This definition is
the same as PS 2 Section 2.1 with the following addition. A continuous
monitor is one in which the sample to be analyzed passes the measurement
section of the analyzer without interruption.
2.2 Response Time. The time interval between the start of a step
change in the system input and when the pollutant analyzer output
reaches 95 percent of the final value.
2.3 Calibration Error (CE). The difference between the concentration
indicated by the CEMS and the known concentration generated by a
calibration source when the entire CEMS, including the sampling
interface is challenged. A CE test procedure is performed to document
the accuracy and linearity of the CEMS over the entire measurement
range.

3. Installation and Measurement Location Specifications

3.1 The CEMS Installation and Measurement Location. This
specification is the same as PS 2 Section 3.1 with the following
additions. Both the CO and O2 monitors should be installed at
the same general location. If this is not possible, they may be
installed at different locations if the effluent gases at both sample
locations are not stratified and there is no in-leakage of air between
sampling locations.
3.1.1 Measurement Location. Same as PS 2 Section 3.1.1.
3.1.2 Point CEMS. The measurement point should be within or
centrally located over the centroidal area of the stack or duct cross
section.
3.1.3 Path CEMS. The effective measurement path should: (1) Have at
least 70 percent of the path within the inner 50 percent of the stack or
duct cross sectional area, or (2) be centrally located over any part of
the centroidal area.
3.2 Reference Method (RM) Measurement Location and Traverse Points.
This specification is the same as PS 2 Section 3.2 with the following
additions. When pollutant concentration changes are due solely to
diluent leakage and CO and O2 are simultaneously measured at
the same location, one half diameter may be used in place of two
equivalent diameters.
3.3 Stratification Test Procedure. Stratification is defined as the
difference in excess of 10 percent between the average concentration in
the duct or stack and the concentration at any point more than 1.0 meter
from the duct or stack wall. To determine whether effluent
stratification exists, a dual probe system should be used to determine
the average effluent concentration while measurements at each traverse
point are being made. One probe, located at the stack or duct centroid,
is used as a stationary reference point to indicate change in the
effluent concentration over time. The second probe is used for sampling
at the traverse points specified in Method 1 (40 CFR part 60 appendix
A). The monitoring system samples sequentially at the reference and
traverse points throughout the testing period for five minutes at each
point.

d. Performance and Equipment Specifications

4.1 Data Recorder Scale. For O2, same as specified in PS
3, except that the span must be 25 percent. The span of the
O2 may be higher if the O2 concentration at the
sampling point can be greater than 25 percent. For CO, same as specified
in PS 4A, except that the low-range span must be 200 ppm and the high
range span must be 3000 ppm. In addition, the scale for both CEMS must
record all readings within a measurement range with a resolution of 0.5
percent.
4.2 Calibration Drift. For O2, same as specified in PS 3.
For CO, the same as specified in PS 4A except that the CEMS calibration
must not drift from the reference value of the calibration standard by
more than 3 percent of the span value on either the high or low range.
4.3 Relative Accuracy (RA). For O2, same as specified in
PS 3. For CO, the same as specified in PS 4A.
4.4 Calibration Error (CE). The mean difference between the CEMS and
reference values at all three test points (see Table I) must be no
greater than 5 percent of span value for CO monitors and 0.5 percent for
O2 monitors.

[[Page 626]]

4.5 Response Time. The response time for the CO or O2
monitor must not exceed 2 minutes.

e. Performance Specification Test Procedure

5.1 Calibration Error Test and Response Time Test Periods. Conduct
the CE and response time tests during the CD test period.

F. The CEMS Calibration Drift and Response Time Test Procedures

The response time test procedure is given in PS 4A, and must be
carried out for both the CO and O2 monitors.
7. Relative Accuracy and Calibration Error Test Procedures
7.1 Calibration Error Test Procedure. Challenge each monitor (both
low and high range CO and O2) with zero gas and EPA Protocol
1 cylinder gases at three measurement points within the ranges specified
in Table I.

Table I. Calibration Error Concentration Ranges
------------------------------------------------------------------------
CO Low
Measurement point range CO High O2 (%)
(ppm) range (ppm)
------------------------------------------------------------------------
1................................. 0-40 0-600 0-2
2................................. 60-80 900-1200 8-10
3................................. 140-160 2100-2400 14-16
------------------------------------------------------------------------

Operate each monitor in its normal sampling mode as nearly as possible.
The calibration gas must be injected into the sample system as close to
the sampling probe outlet as practical and should pass through all CEMS
components used during normal sampling. Challenge the CEMS three non-
consecutive times at each measurement point and record the responses.
The duration of each gas injection should be sufficient to ensure that
the CEMS surfaces are conditioned.
7.1.1 Calculations. Summarize the results on a data sheet. Average
the differences between the instrument response and the certified
cylinder gas value for each gas. Calculate the CE results according to:
[GRAPHIC] [TIFF OMITTED] TR30SE99.010

where d is the mean difference between the CEMS response and the known
reference concentration and FS is the span value.

7.2 Relative Accuracy Test Procedure. Follow the RA test procedures
in PS 3 (for O2) section 3 and PS 4A (for CO) section 4.
7.3 Alternative RA Procedure. Under some operating conditions, it
may not be possible to obtain meaningful results using the RA test
procedure. This includes conditions where consistent, very low CO
emission or low CO emissions interrupted periodically by short duration,
high level spikes are observed. It may be appropriate in these
circumstances to waive the RA test and substitute the following
procedure.
Conduct a complete CEMS status check following the manufacturer's
written instructions. The check should include operation of the light
source, signal receiver, timing mechanism functions, data acquisition
and data reduction functions, data recorders, mechanically operated
functions, sample filters, sample line heaters, moisture traps, and
other related functions of the CEMS, as applicable. All parts of the
CEMS must be functioning properly before the RA requirement can be
waived. The instrument must also successfully passed the CE and CD
specifications. Substitution of the alternate procedure requires
approval of the Regional Administrator.
8. Bibliography
1. 40 CFR Part 266, Appendix IX, Section 2, ``Performance
Specifications for Continuous Emission Monitoring Systems.''

Performance Specification 5--Specifications and Test Procedures for TRS
Continuous Emission Monitoring Systems in Stationary Sources

1.0 Scope and Application

1.1 Analytes.

------------------------------------------------------------------------
Analyte CAS No.
------------------------------------------------------------------------
Total Reduced Sulfur (TRS)............................. NA
------------------------------------------------------------------------

1.2 Applicability. This specification is for evaluating the
applicability of TRS continuous emission monitoring systems (CEMS) at
the time of installation or soon after and whenever specified in an
applicable subpart of the regulations. The CEMS may include oxygen
monitors which are subject to Performance Specification 3 (PS 3).
1.3 The definitions, performance specification, test procedures,
calculations and data analysis procedures for determining calibration
drifts (CD) and relative accuracy (RA) of PS 2, Sections 3.0, 8.0, and
12.0, respectively, apply to this specification.

2.0 Summary of Performance Specification

The CD and RA tests are conducted to determine conformance of the
CEMS to the specification.

3.0 Definitions

Same as in Section 3.0 of PS 2.

4.0 Interferences [Reserved]

5.0 Safety

[[Page 627]]

safety and health practices and determine the applicable regulatory
limitations prior to performing this performance specification. The CEMS
users manual should be consulted for specific precautions to be taken
with regard to the analytical procedures.

6.0 Equipment and Supplies

Same as Section 6.0 of PS 2.

7.0 Reagents and Standards

Same as Section 7.0 of PS 2.

8.0 Sample Collection, Preservation, Storage, and Transport

Note: For Method 16, a sample is made up of at least three separate
injects equally space over time. For Method 16A, a sample is collected
for at least 1 hour.

8.2 Reference Methods. Unless otherwise specified in the applicable
subpart of the regulations, Method 16, Method 16A, 16B or other approved
alternative is the RM for TRS.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Sample collection and analysis are concurrent for this performance
specification (see Section 8.0). Refer to the reference method for
specific analytical procedures.

12.0 Calculations and Data Analysis

Same as Section 12.0 of PS 2.

13.0 Method Performance

13.1 Calibration Drift. The CEMS detector calibration must not drift
or deviate from the reference value of the calibration gas by more than
5 percent of the established span value for 6 out of 7 test days. This
corresponds to 1.5 ppm drift for Subpart BB sources where the span value
is 30 ppm. If the CEMS includes pollutant and diluent monitors, the CD
must be determined separately for each in terms of concentrations (see
PS 3 for the diluent specifications).
13.2 Relative Accuracy. The RA of the CEMS must be no greater than
20 percent when the average RM value is used to calculate RA or 10
percent when the applicable emission standard is used to calculate RA.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Alternative Procedures [Reserved]

17.0 References

1. Department of Commerce. Experimental Statistics, National Bureau
of Standards, Handbook 91. 1963. Paragraphs 3-3.1.4, p. 3-31.
2. A Guide to the Design, Maintenance and Operation of TRS
Monitoring Systems. National Council for Air and Stream Improvement
Technical Bulletin No. 89. September 1977.
3. Observation of Field Performance of TRS Monitors on a Kraft
Recovery Furnace. National Council for Air and Stream Improvement
Technical Bulletin No. 91. January 1978.

18.0 Tables, Diagrams, Flowcharts, and Validation Data

Same as Section 18.0 of PS 2.

Performance Specification 6--Specifications and Test Procedures for
Continuous Emission Rate Monitoring Systems in Stationary Sources

1.0 Scope and Application

1.1 Applicability. This specification is used for evaluating the
acceptability of continuous emission rate monitoring systems (CERMSs).
1.2 The installation and measurement location specifications,
performance specification test procedure, calculations, and data
analysis procedures, of Performance Specifications (PS 2), Sections 8.0
and 12, respectively, apply to this specification.

2.0 Summary of Performance Specification

The calibration drift (CD) and relative accuracy (RA) tests are
conducted to determine conformance of the CERMS to the specification.

3.0 Definitions

The definitions are the same as in Section 3 of PS 2, except this
specification refers to the continuous emission rate monitoring system
rather than the continuous emission monitoring system. The following
definitions are added:
3.1 Continuous Emission Rate Monitoring System (CERMS). The total
equipment required for the determining and recording the pollutant mass
emission rate (in terms of mass per unit of time).
3.2 Flow Rate Sensor. That portion of the CERMS that senses the
volumetric flow rate and generates an output proportional to that flow
rate. The flow rate sensor shall have provisions to check the CD for
each flow rate

[[Page 628]]

parameter that it measures individually (e.g., velocity, pressure).

4.0 Interferences [Reserved]

5.0 Safety

This performance specification may involve hazardous materials,
operations, and equipment. This performance specification may not
address all of the safety problems associated with its use. It is the
responsibility of the user to establish appropriate safety and health
practices and determine the applicable regulatory limitations prior to
performing this performance specification. The CERMS users manual should
be consulted for specific precautions to be taken with regard to the
analytical procedures.

6.0 Equipment and Supplies

Same as Section 6.0 of PS 2.

7.0 Reagents and Standards

Same as Section 7.0 of PS 2.

8.0 Sample Collection, Preservation, Storage, and Transport

8.1 Calibration Drift Test Procedure.
8.1.1 The CD measurements are to verify the ability of the CERMS to
conform to the established CERMS calibrations used for determining the
emission rate. Therefore, if periodic automatic or manual adjustments
are made to the CERMS zero and calibration settings, conduct the CD
tests immediately before these adjustments, or conduct them in such a
way that CD can be determined.
8.1.2 Conduct the CD tests for pollutant concentration at the two
values specified in Section 6.1.2 of PS 2. For other parameters that are
selectively measured by the CERMS (e.g., velocity, pressure, flow rate),
use two analogous values (e.g., Low: 0-20% of full scale, High: 50-100%
of full scale). Introduce to the CERMS the reference signals (these need
not be certified). Record the CERMS response to each and subtract this
value from the respective reference value (see example data sheet in
Figure 6-1).
8.2 Relative Accuracy Test Procedure.
8.2.1 Sampling Strategy for reference method (RM) Tests, Correlation
of RM and CERMS Data, and Number of RM Tests are the same as PS 2,
Sections 8.4.3, 8.4.5, and 8.4.4, respectively. Summarize the results on
a data sheet. An example is shown in Figure 6-1. The RA test may be
conducted during the CD test period.
8.2.2 Reference Methods. Unless otherwise specified in the
applicable subpart of the regulations, the RM for the pollutant gas is
the Appendix A method that is cited for compliance test purposes, or its
approved alternatives. Methods 2, 2A, 2B, 2C, or 2D, as applicable, are
the RMs for the determination of volumetric flow rate.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Same as Section 11.0 of PS 2.

12.0 Calculations and Data Analysis

Same as Section 12.0 of PS 2.

13.0 Method Performance

13.1 Calibration Drift. Since the CERMS includes analyzers for
several measurements, the CD shall be determined separately for each
analyzer in terms of its specific measurement. The calibration for each
analyzer associated with the measurement of flow rate shall not drift or
deviate from each reference value of flow rate by more than 3 percent of
the respective high-level value. The CD specification for each analyzer
for which other PSs have been established (e.g., PS 2 for SO2
and NOX), shall be the same as in the applicable PS.
13.2 CERMS Relative Accuracy. The RA of the CERMS shall be no
greater than 20 percent of the mean value of the RM's test data in terms
of the units of the emission standard, or 10 percent of the applicable
standard, whichever is greater.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Alternative Procedures

Same as in Section 16.0 of PS 2.

17.0 References

1. Brooks, E.F., E.C. Beder, C.A. Flegal, D.J. Luciani, and R.
Williams. Continuous Measurement of Total Gas Flow Rate from Stationary
Sources. U.S. Environmental Protection Agency. Research Triangle Park,
North Carolina. Publication No. EPA-650/2-75-020. February 1975. 248 p.

18.0 Tables, Diagrams, Flowcharts, and Validation Data

----------------------------------------------------------------------------------------------------------------
Emission rate (kg/hr)a
--------------------------------------------------------------------
Run No. Date and time Difference (RMs-
CERMS RMs CERMS)
----------------------------------------------------------------------------------------------------------------
1 .....................
--------------------

[[Page 629]]

2 .....................
--------------------
3 .....................
--------------------
4 .....................
--------------------
5 .....................
--------------------
6 .....................
--------------------
7 .....................
--------------------
8 .....................
--------------------
9 .....................
----------------------------------------------------------------------------------------------------------------
\a\ The RMs and CERMS data as corrected to a consistent basis (i.e., moisture, temperature, and pressure
conditions).

Figure 6-1--Emission Rate Determinations

Performance Specification 7--Specifications and Test Procedures for
Hydrogen Sulfide Continuous Emission Monitoring Systems in Stationary
Sources

1.0 Scope and Application

1.1 Analytes.

------------------------------------------------------------------------
Analyte CAS No.
------------------------------------------------------------------------
Hydrogen Sulfide........................................ 7783-06-4
------------------------------------------------------------------------

1.2 Applicability.
1.2.1 This specification is to be used for evaluating the
acceptability of hydrogen sulfide (H2S) continuous emission
monitoring systems (CEMS) at the time of or soon after installation and
whenever specified in an applicable subpart of the regulations.
1.2.2 This specification is not designed to evaluate the installed
CEMS performance over an extended period of time nor does it identify
specific calibration techniques and other auxiliary procedures to assess
CEMS performance. The source owner or operator, however, is responsible
to calibrate, maintain, and operate the CEMS. To evaluate CEMS
performance, the Administrator may require, under Section 114 of the
Act, the source owner or operator to conduct CEMS performance
evaluations at other times besides the initial test. See Section
60.13(c).

2.0 Summary

Calibration drift (CD) and relative accuracy (RA) tests are
conducted to determine that the CEMS conforms to the specification.

3.0 Definitions

Same as Section 3.0 of PS 2.

4.0 Interferences [Reserved]

5.0 Safety

The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This performance
specification may not address all of the safety problems associated with
these procedures. It is the responsibility of the user to establish
appropriate safety problems associated with these procedures. It is the
responsibility of the user to establish appropriate safety and health
practices and determine the application regulatory limitations prior to
performing these procedures. The CEMS user's manual and materials
recommended by the reference method should be consulted for specific
precautions to be taken.

6.0 Equipment and Supplies

6.1 Instrument Zero and Span. This specification is the same as
Section 6.1 of PS 2.
6.2 Calibration Drift. The CEMS calibration must not drift or
deviate from the reference value of the calibration gas or reference
source by more than 5 percent of the established span value for 6 out of
7 test days (e.g., the established span value is 300 ppm for Subpart J
fuel gas combustion devices).
6.3 Relative Accuracy. The RA of the CEMS must be no greater than 20
percent when the average reference method (RM) value is used to
calculate RA or 10 percent when the applicable emission standard is used
to calculate RA.

7.0 Reagents and Standards

Same as Section 7.0 of PS 2.

8.0 Sample Collection, Preservation, Storage, and Transport.

8.1 Installation and Measurement Location Specification. Same as
Section 8.1 of PS 2.

[[Page 630]]

8.2 Pretest Preparation. Same as Section 8.2 of PS 2.
8.3 Calibration Drift Test Procedure. Same as Section 8.3 of PS 2.
8.4 Relative Accuracy Test Procedure.
8.4.1 Sampling Strategy for RM Tests, Correlation of RM and CEMS
Data, and Number of RM Tests. These are the same as that in PS 2,
Sections 8.4.3, 8.4.5, and 8.4.4, respectively.
8.4.2 Reference Methods. Unless otherwise specified in an applicable
subpart of the regulation, Method 11 is the RM for this PS.
8.5 Reporting. Same as Section 8.5 of PS 2.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardizations [Reserved]

11.0 Analytical Procedures

Sample Collection and analysis are concurrent for this PS (see
Section 8.0). Refer to the RM for specific analytical procedures.

12.0 Data Analysis and Calculations

Same as Section 12.0 of PS 2.

13.0 Method Performance [Reserved]

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 References

1. U.S. Environmental Protection Agency. Standards of Performance
for New Stationary Sources; Appendix B; Performance Specifications 2 and
3 for SO2, NOX, CO2, and O2
Continuous Emission Monitoring Systems; Final Rule. 48 CFR 23608.
Washington, D.C. U.S. Government Printing Office. May 25, 1983.
2. U.S. Government Printing Office. Gaseous Continuous Emission
Monitoring Systems--Performance Specification Guidelines for
SO2, NOX, CO2, O2, and TRS.
U.S. Environmental Protection Agency. Washington, D.C. EPA-450/3-82-026.
October 1982. 26 p.
3. Maines, G.D., W.C. Kelly (Scott Environmental Technology, Inc.),
and J.B. Homolya. Evaluation of Monitors for Measuring H2S in
Refinery Gas. Prepared for the U.S. Environmental Protection Agency.
Research Triangle Park, N.C. Contract No. 68-02-2707. 1978. 60 p.
4. Ferguson, B.B., R.E. Lester (Harmon Engineering and Testing), and
W.J. Mitchell. Field Evaluation of Carbon Monoxide and Hydrogen Sulfide
Continuous Emission Monitors at an Oil Refinery. Prepared for the U.S.
Environmental Protection Agency. Research Triangle Park, N.C.
Publication No. EPA-600/4-82-054. August 1982. 100 p.

17.0 Tables, Diagrams, Flowcharts, and Validation Data

Same as Section 18.0 of PS 2.

Performance Specification 8--Performance Specifications for Volatile
Organic Compound Continuous Emission Monitoring Systems in Stationary
Sources

1.0 Scope and Application

1.1 Analytes. Volatile Organic Compounds (VOCs).
1.2 Applicability.
1.2.1 This specification is to be used for evaluating a continuous
emission monitoring system (CEMS) that measures a mixture of VOC's and
generates a single combined response value. The VOC detection principle
may be flame ionization (FI), photoionization (PI), non-dispersive
infrared absorption (NDIR), or any other detection principle that is
appropriate for the VOC species present in the emission gases and that
meets this performance specification. The performance specification
includes procedures to evaluate the acceptability of the CEMS at the
time of or soon after its installation and whenever specified in
emission regulations or permits. This specification is not designed to
evaluate the installed CEMS performance over an extended period of time,
nor does it identify specific calibration techniques and other auxiliary
procedures to assess the CEMS performance. The source owner or operator,
however, is responsible to calibrate, maintain, and operate the CEMS
properly. To evaluate the CEMS performance, the Administrator may
require, under Section 114 of the Act, the operator to conduct CEMS
performance evaluations in addition to the initial test. See Section
60.13(c).
1.2.2 In most emission circumstances, most VOC monitors can provide
only a relative measure of the total mass or volume concentration of a
mixture of organic gases, rather than an accurate quantification. This
problem is removed when an emission standard is based on a total VOC
measurement as obtained with a particular detection principle. In those
situations where a true mass or volume VOC concentration is needed, the
problem can be mitigated by using the VOC CEMS as a relative indicator
of total VOC concentration if statistical analysis indicates that a
sufficient margin of compliance exists for this approach to be
acceptable. Otherwise, consideration can be given to calibrating the
CEMS with a mixture of the same VOC's in the same proportions as they
actually occur in the measured source. In those circumstances where only
one organic species is present in the source, or where equal incremental
amounts of each of the organic species present generate equal CEMS

[[Page 631]]

responses, the latter choice can be more easily achieved.

2.0 Summary of Performance Specification

2.1 Calibration drift and relative accuracy tests are conducted to
determine adherence of the CEMS with specifications given for those
items. The performance specifications include criteria for installation
and measurement location, equipment and performance, and procedures for
testing and data reduction.

3.0 Definitions.

Same as Section 3.0 of PS 2.

4.0 Interferences [Reserved]

5.0 Safety

The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This performance
specification may not address all of the safety problems associated with
these procedures. It is the responsibility of the user to establish
appropriate safety problems associated with these procedures. It is the
responsibility of the user to establish appropriate safety and health
practices and determine the application regulatory limitations prior to
performing these procedures. The CEMS user's manual and materials
recommended by the reference method should be consulted for specific
precautions to be taken.

6.0 Equipment and Supplies

6.1 VOC CEMS Selection. When possible, select a VOC CEMS with the
detection principle of the reference method specified in the regulation
or permit (usually either FI, NDIR, or PI). Otherwise, use knowledge of
the source process chemistry, previous emission studies, or gas
chromatographic analysis of the source gas to select an appropriate VOC
CEMS. Exercise extreme caution in choosing and installing any CEMS in an
area with explosive hazard potential.
6.2 Data Recorder Scale. Same as Section 6.1 of PS 2.

7.0 Reagents and Standards [Reserved]

8.0 Sample Collection, Preservation, Storage, and Transport

8.1 Installation and Measurement Location Specifications. Same as
Section 8.1 of PS 2.
8.2 Pretest Preparation. Same as Section 8.2 of PS 2.
8.3 Reference Method (RM). Use the method specified in the
applicable regulation or permit, or any approved alternative, as the RM.
8.4 Sampling Strategy for RM Tests, Correlation of RM and CEMS Data,
and Number of RM Tests. Follow PS 2, Sections 8.4.3, 8.4.5, and 8.4.4,
respectively.
8.5 Reporting. Same as Section 8.5 of PS 2.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization [Reserved]

11.0 Analytical Procedure

Sample collection and analysis are concurrent for this PS (see
Section 8.0). Refer to the RM for specific analytical procedures.

12.0 Calculations and Data Analysis

Same as Section 12.0 of PS 2.

13.0 Method Performance

13.1 Calibration Drift. The CEMS calibration must not drift by more
than 2.5 percent of the span value.
13.2 CEMS Relative Accuracy. Unless stated otherwise in the
regulation or permit, the RA of the CEMS must not be greater than 20
percent of the mean value of the RM test data in terms of the units of
the emission standard, or 10 percent of the applicable standard,
whichever is greater.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 References

Same as Section 17.0 of PS 2.

17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]

Performance Specification 8A--Specifications and Test Procedures for
Total Hydrocarbon Continuous Monitoring Systems in Stationary Sources

1. Applicability and Principle

1.1 Applicability. These performance specifications apply to
hydrocarbon (HC) continuous emission monitoring systems (CEMS) installed
on stationary sources. The specifications include procedures which are
intended to be used to evaluate the acceptability of the CEMS at the
time of its installation or whenever specified in regulations or
permits. The procedures are not designed to evaluate CEMS performance
over an extended period of time. The source owner or operator is
responsible for the proper calibration, maintenance, and operation of
the CEMS at all times.
1.2 Principle. A gas sample is extracted from the source through a
heated sample line and heated filter to a flame ionization detector
(FID). Results are reported as volume concentration equivalents of
propane.

[[Page 632]]

Installation and measurement location specifications, performance and
equipment specifications, test and data reduction procedures, and brief
quality assurance guidelines are included in the specifications.
Calibration drift, calibration error, and response time tests are
conducted to determine conformance of the CEMS with the specifications.

2. Definitions

2.1 Continuous Emission Monitoring System (CEMS). The total
equipment used to acquire data, which includes sample extraction and
transport hardware, analyzer, data recording and processing hardware,
and software. The system consists of the following major subsystems:
2.1.1 Sample Interface. That portion of the system that is used for
one or more of the following: Sample acquisition, sample transportation,
sample conditioning, or protection of the analyzer from the effects of
the stack effluent.
2.1.2 Organic Analyzer. That portion of the system that senses
organic concentration and generates an output proportional to the gas
concentration.
2.1.3 Data Recorder. That portion of the system that records a
permanent record of the measurement values. The data recorder may
include automatic data reduction capabilities.
2.2 Instrument Measurement Range. The difference between the minimum
and maximum concentration that can be measured by a specific instrument.
The minimum is often stated or assumed to be zero and the range
expressed only as the maximum.
2.3 Span or Span Value. Full scale instrument measurement range. The
span value must be documented by the CEMS manufacturer with laboratory
data.
2.4 Calibration Gas. A known concentration of a gas in an
appropriate diluent gas.
2.5 Calibration Drift (CD). The difference in the CEMS output
readings from the established reference value after a stated period of
operation during which no unscheduled maintenance, repair, or adjustment
takes place. A CD test is performed to demonstrate the stability of the
CEMS calibration over time.
2.6 Response Time. The time interval between the start of a step
change in the system input (e.g., change of calibration gas) and the
time when the data recorder displays 95 percent of the final value.
2.7 Accuracy. A measurement of agreement between a measured value
and an accepted or true value, expressed as the percentage difference
between the true and measured values relative to the true value. For
these performance specifications, accuracy is checked by conducting a
calibration error (CE) test.
2.8 Calibration Error (CE). The difference between the concentration
indicated by the CEMS and the known concentration of the cylinder gas. A
CE test procedure is performed to document the accuracy and linearity of
the monitoring equipment over the entire measurement range.
2.9 Performance Specification Test (PST) Period. The period during
which CD, CE, and response time tests are conducted.
2.10 Centroidal Area. A concentric area that is geometrically
similar to the stack or duct cross section and is no greater than 1
percent of the stack or duct cross-sectional area.

3. Installation and Measurement Location Specifications

3.1 CEMS Installation and Measurement Locations. The CEMS must be
installed in a location in which measurements representative of the
source's emissions can be obtained. The optimum location of the sample
interface for the CEMS is determined by a number of factors, including
ease of access for calibration and maintenance, the degree to which
sample conditioning will be required, the degree to which it represents
total emissions, and the degree to which it represents the combustion
situation in the firebox (where applicable). The location should be as
free from in-leakage influences as possible and reasonably free from
severe flow disturbances. The sample location should be at least two
equivalent duct diameters downstream from the nearest control device,
point of pollutant generation, or other point at which a change in the
pollutant concentration or emission rate occurs and at least 0.5
diameter upstream from the exhaust or control device. The equivalent
duct diameter is calculated as per 40 CFR part 60, appendix A, method 1,
section 2.1. If these criteria are not achievable or if the location is
otherwise less than optimum, the possibility of stratification should be
investigated as described in section 3.2. The measurement point must be
within the centroidal area of the stack or duct cross section.
3.2 Stratification Test Procedure. Stratification is defined as a
difference in excess of 10 percent between the average concentration in
the duct or stack and the concentration at any point more than 1.0 meter
from the duct or stack wall. To determine whether effluent
stratification exists, a dual probe system should be used to determine
the average effluent concentration while measurements at each traverse
point are being made. One probe, located at the stack or duct centroid,
is used as a stationary reference point to indicate the change in
effluent concentration over time. The second probe is used for sampling
at the traverse points specified in 40 CFR part 60 appendix A, method 1.
The monitoring system samples sequentially at the

[[Page 633]]

reference and traverse points throughout the testing period for five
minutes at each point.

4. CEMS Performance and Equipment Specifications

If this method is applied in highly explosive areas, caution and
care must be exercised in choice of equipment and installation.
4.1 Flame Ionization Detector (FID) Analyzer. A heated FID analyzer
capable of meeting or exceeding the requirements of these
specifications. Heated systems must maintain the temperature of the
sample gas between 150 [deg]C (300 [deg]F) and 175 [deg]C (350 [deg]F)
throughout the system. This requires all system components such as the
probe, calibration valve, filter, sample lines, pump, and the FID to be
kept heated at all times such that no moisture is condensed out of the
system. The essential components of the measurement system are described
below:
4.1.1 Sample Probe. Stainless steel, or equivalent, to collect a gas
sample from the centroidal area of the stack cross-section.
4.1.2 Sample Line. Stainless steel or Teflon tubing to transport the
sample to the analyzer.

Note: Mention of trade names or specific products does not
constitute endorsement by the Environmental Protection Agency.

4.1.3 Calibration Valve Assembly. A heated three-way valve assembly
to direct the zero and calibration gases to the analyzer is recommended.
Other methods, such as quick-connect lines, to route calibration gas to
the analyzers are applicable.
4.1.4 Particulate Filter. An in-stack or out-of-stack sintered
stainless steel filter is recommended if exhaust gas particulate loading
is significant. An out-of-stack filter must be heated.
4.1.5 Fuel. The fuel specified by the manufacturer (e.g., 40 percent
hydrogen/60 percent helium, 40 percent hydrogen/60 percent nitrogen gas
mixtures, or pure hydrogen) should be used.
4.1.6 Zero Gas. High purity air with less than 0.1 parts per million
by volume (ppm) HC as methane or carbon equivalent or less than 0.1
percent of the span value, whichever is greater.
4.1.7 Calibration Gases. Appropriate concentrations of propane gas
(in air or nitrogen). Preparation of the calibration gases should be
done according to the procedures in EPA Protocol 1. In addition, the
manufacturer of the cylinder gas should provide a recommended shelf life
for each calibration gas cylinder over which the concentration does not
change by more than 2 percent from the certified
value.
4.2 CEMS Span Value. 100 ppm propane. The span value must be
documented by the CEMS manufacturer with laboratory data.
4.3 Daily Calibration Gas Values. The owner or operator must choose
calibration gas concentrations that include zero and high-level
calibration values.
4.3.1 The zero level may be between zero and 0.1 ppm (zero and 0.1
percent of the span value).
4.3.2 The high-level concentration must be between 50 and 90 ppm (50
and 90 percent of the span value).
4.4 Data Recorder Scale. The strip chart recorder, computer, or
digital recorder must be capable of recording all readings within the
CEMS' measurement range and must have a resolution of 0.5 ppm (0.5
percent of span value).
4.5 Response Time. The response time for the CEMS must not exceed 2
minutes to achieve 95 percent of the final stable value.
4.6 Calibration Drift. The CEMS must allow the determination of CD
at the zero and high-level values. The CEMS calibration response must
not differ by more than 3 ppm (3 percent of the span value) after each 24-hour period
of the 7-day test at both zero and high levels.
4.7 Calibration Error. The mean difference between the CEMS and
reference values at all three test points listed below must be no
greater than 5 ppm (5 percent of the span value).
4.7.1 Zero Level. Zero to 0.1 ppm (0 to 0.1 percent of span value).
4.7.2 Mid-Level. 30 to 40 ppm (30 to 40 percent of span value).
4.7.3 High-Level. 70 to 80 ppm (70 to 80 percent of span value).
4.8 Measurement and Recording Frequency. The sample to be analyzed
must pass through the measurement section of the analyzer without
interruption. The detector must measure the sample concentration at
least once every 15 seconds. An average emission rate must be computed
and recorded at least once every 60 seconds.
4.9 Hourly Rolling Average Calculation. The CEMS must calculate
every minute an hourly rolling average, which is the arithmetic mean of
the 60 most recent 1-minute average values.
4.10 Retest. If the CEMS produces results within the specified
criteria, the test is successful. If the CEMS does not meet one or more
of the criteria, necessary corrections must be made and the performance
tests repeated.

5. Performance Specification Test (PST) Periods

5.1 Pretest Preparation Period. Install the CEMS, prepare the PTM
test site according to the specifications in section 3, and prepare the
CEMS for operation and calibration according to the manufacturer's
written instructions. A pretest conditioning period

[[Page 634]]

similar to that of the 7-day CD test is recommended to verify the
operational status of the CEMS.
5.2 Calibration Drift Test Period. While the facility is operating
under normal conditions, determine the magnitude of the CD at 24-hour
intervals for seven consecutive days according to the procedure given in
section 6.1. All CD determinations must be made following a 24-hour
period during which no unscheduled maintenance, repair, or adjustment
takes place. If the combustion unit is taken out of service during the
test period, record the onset and duration of the downtime and continue
the CD test when the unit resumes operation.
5.3 Calibration Error Test and Response Time Test Periods. Conduct
the CE and response time tests during the CD test period.

6. Performance Specification Test Procedures

6.1 Relative Accuracy Test Audit (RATA) and Absolute Calibration
Audits (ACA). The test procedures described in this section are in lieu
of a RATA and ACA.
6.2 Calibration Drift Test.
6.2.1 Sampling Strategy. Conduct the CD test at 24-hour intervals
for seven consecutive days using calibration gases at the two daily
concentration levels specified in section 4.3. Introduce the two
calibration gases into the sampling system as close to the sampling
probe outlet as practical. The gas must pass through all CEM components
used during normal sampling. If periodic automatic or manual adjustments
are made to the CEMS zero and calibration settings, conduct the CD test
immediately before these adjustments, or conduct it in such a way that
the CD can be determined. Record the CEMS response and subtract this
value from the reference (calibration gas) value. To meet the
specification, none of the differences may exceed 3 percent of the span
of the CEM.
6.2.2 Calculations. Summarize the results on a data sheet. An
example is shown in Figure 1. Calculate the differences between the CEMS
responses and the reference values.
6.3 Response Time. The entire system including sample extraction and
transport, sample conditioning, gas analyses, and the data recording is
checked with this procedure.
6.3.1 Introduce the calibration gases at the probe as near to the
sample location as possible. Introduce the zero gas into the system.
When the system output has stabilized (no change greater than 1 percent
of full scale for 30 sec), switch to monitor stack effluent and wait for
a stable value. Record the time (upscale response time) required to
reach 95 percent of the final stable value.
6.3.2 Next, introduce a high-level calibration gas and repeat the
above procedure. Repeat the entire procedure three times and determine
the mean upscale and downscale response times. The longer of the two
means is the system response time.
6.4 Calibration Error Test Procedure.
6.4.1 Sampling Strategy. Challenge the CEMS with zero gas and EPA
Protocol 1 cylinder gases at measurement points within the ranges
specified in section 4.7.
6.4.1.1 The daily calibration gases, if Protocol 1, may be used for
this test.

[[Page 635]]

[GRAPHIC] [TIFF OMITTED] TR30SE99.011

6.4.1.2 Operate the CEMS as nearly as possible in its normal
sampling mode. The calibration gas should be injected into the sampling
system as close to the sampling probe outlet as practical and must pass
through all filters, scrubbers, conditioners, and other monitor
components used during normal sampling. Challenge the CEMS three non-
consecutive times at each measurement point and record the responses.
The duration of each gas injection should be for a sufficient period of
time to ensure that the CEMS surfaces are conditioned.
6.4.2 Calculations. Summarize the results on a data sheet. An
example data sheet is shown in Figure 2. Average the differences between
the instrument response and the certified cylinder gas value for each
gas. Calculate three CE results according to Equation 1. No confidence
coefficient is used in CE calculations.

7. Equations

Calibration Error. Calculate CE using Equation 1.
[GRAPHIC] [TIFF OMITTED] TR30SE99.012

Where:

d=Mean difference between CEMS response and the known reference
concentration, determined using Equation 2.

[[Page 636]]

[GRAPHIC] [TIFF OMITTED] TR30SE99.013

Where:

di=Individual difference between CEMS response and the known
reference concentration.

8. Reporting

At a minimum, summarize in tabular form the results of the CD,
response time, and CE test, as appropriate. Include all data sheets,
calculations, CEMS data records, and cylinder gas or reference material
certifications.
[GRAPHIC] [TIFF OMITTED] TR30SE99.014

9. References

1. Measurement of Volatile Organic Compounds-Guideline Series. U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina,
27711, EPA-450/2-78-041, June 1978.
2. Traceability Protocol for Establishing True Concentrations of
Gases Used for Calibration and Audits of Continuous Source Emission
Monitors (Protocol No. 1). U.S. Environmental Protection Agency ORD/
EMSL, Research Triangle Park, North Carolina, 27711, June 1978.
3. Gasoline Vapor Emission Laboratory Evaluation-Part 2. U.S.
Environmental Protection Agency, OAQPS, Research Triangle Park, North
Carolina, 27711, EMB Report No. 76-GAS-6, August 1975.

[[Page 637]]

Performance Specification 9--Specifications and Test Procedures for Gas
Chromatographic Continuous Emission Monitoring Systems in Stationary
Sources

1.0 Scope and Application

1.1 Applicability. These requirements apply to continuous emission
monitoring systems (CEMSs) that use gas chromatography (GC) to measure
gaseous organic compound emissions. The requirements include procedures
intended to evaluate the acceptability of the CEMS at the time of its
installation and whenever specified in regulations or permits. Quality
assurance procedures for calibrating, maintaining, and operating the
CEMS properly at all times are also given in this procedure.

2.0 Summary of Performance Specification

2.1 Calibration precision, calibration error, and performance audit
tests are conducted to determine conformance of the CEMS with these
specifications. Daily calibration and maintenance requirements are also
specified.

3.0 Definitions

3.1 Gas Chromatograph (GC). That portion of the system that
separates and detects organic analytes and generates an output
proportional to the gas concentration. The GC must be temperature
controlled.

Note: The term temperature controlled refers to the ability to
maintain a certain temperature around the column. Temperature-
programmable GC is not required for this performance specification, as
long as all other requirements for precision, linearity and accuracy
listed in this performance specification are met. It should be noted
that temperature programming a GC will speed up peak elution, thus
allowing increased sampling frequency.

3.1.1 Column. Analytical column capable of separating the analytes
of interest.
3.1.2 Detector. A detection system capable of detecting and
quantifying all analytes of interest.
3.1.3 Integrator. That portion of the system that quantifies the
area under a particular sample peak generated by the GC.
3.1.4 Data Recorder. A strip chart recorder, computer, or digital
recorder capable of recording all readings within the instrument's
calibration range.
3.2 Calibration Precision. The error between triplicate injections
of each calibration standard.

4.0 Interferences [Reserved]

5.0 Safety

The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This performance
specification does not purport to address all of the safety problems
associated with these procedures. It is the responsibility of the user
to establish appropriate safety problems associated with these
procedures. It is the responsibility of the user to establish
appropriate safety and health practices and determine the application
regulatory limitations prior to performing these procedures. The CEMS
user's manual and materials recommended by the reference method should
be consulted for specific precautions to be taken.

6.0 Equipment and Supplies

6.1 Presurvey Sample Analysis and GC Selection. Determine the
pollutants to be monitored from the applicable regulation or permit and
determine the approximate concentration of each pollutant (this
information can be based on past compliance test results). Select an
appropriate GC configuration to measure the organic compounds. The GC
components should include a heated sample injection loop (or other
sample introduction systems), separatory column, temperature-controlled
oven, and detector. If the source chooses dual column and/or dual
detector configurations, each column/detector is considered a separate
instrument for the purpose of this performance specification and thus
the procedures in this performance specification shall be carried out on
each system. If this method is applied in highly explosive areas,
caution should be exercised in selecting the equipment and method of
installation.
6.2 Sampling System. The sampling system shall be heat traced and
maintained at a minimum of 120 [deg]C with no cold spots. All system
components shall be heated, including the probe, calibration valve,
sample lines, sampling loop (or sample introduction system), GC oven,
and the detector block (when appropriate for the type of detector being
utilized, e.g., flame ionization detector).

7.0 Reagents and Standards

7.1 Calibration Gases. Obtain three concentrations of calibration
gases certified by the manufacturer to be accurate to within 2 percent
of the value on the label. A gas dilution system may be used to prepare
the calibration gases from a high concentration certified standard if
the gas dilution system meets the requirements specified in Test Method
205, 40 CFR Part 51, Appendix M. The performance test specified in Test
Method 205 shall be repeated quarterly, and the results of the Method
205 test shall be included in the report. The calibration gas
concentration of each target analyte shall be as follows (measured
concentration is based on the

[[Page 638]]

presurvey concentration determined in Section 6.1).

Note: If the low level calibration gas concentration falls at or
below the limit of detection for the instrument for any target
pollutant, a calibration gas with a concentration at 4 to 5 times the
limit of detection for the instrument may be substituted for the low-
level calibration gas listed in Section 7.1.1.

7.1.1 Low-level. 40-60 percent of measured concentration.
7.1.2 Mid-level. 90-110 percent of measured concentration.
7.1.3 High-level. 140-160 percent of measured concentration, or
select highest expected concentration.
7.2 Performance Audit Gas. A certified EPA audit gas shall be used,
when possible. A gas mixture containing all the target compounds within
the calibration range and certified by EPA's Traceability Protocol for
Assay and Certification of Gaseous Calibration Standards may be used
when EPA performance audit materials are not available. The instrument
relative error shall be <= 10 percent of the certified value of the
audit gas.

8.0 Sample Collection, Preservation, Storage, and Transport

8.1 Installation and Measurement Location Specifications. Install
the CEMs in a location where the measurements are representative of the
source emissions. Consider other factors, such as ease of access for
calibration and maintenance purposes. The location should not be close
to air in-leakages. The sampling location should be at least two
equivalent duct diameters downstream from the nearest control device,
point of pollutant generation, or other point at which a change in the
pollutant concentration or emission rate occurs. The location should be
at least 0.5 diameter upstream from the exhaust or control device. To
calculate equivalent duct diameter, see Section 12.2 of Method 1 (40 CFR
Part 60, Appendix A). Sampling locations not conforming to the
requirements in this section may be used if necessary upon approval of
the Administrator.
8.2 Pretest Preparation Period. Using the procedures described in
Method 18
(40 CFR Part 60, Appendix A), perform initial tests to determine GC
conditions that provide good resolution and minimum analysis time for
compounds of interest. Resolution interferences that may occur can be
eliminated by appropriate GC column and detector choice or by shifting
the retention times through changes in the column flow rate and the use
of temperature programming.
8.3 7-Day Calibration Error (CE) Test Period. At the beginning of
each 24-hour period, set the initial instrument setpoints by conducting
a multi-point calibration for each compound. The multi-point calibration
shall meet the requirements in Section 13.3. Throughout the 24-hour
period, sample and analyze the stack gas at the sampling intervals
prescribed in the regulation or permit. At the end of the 24 hour
period, inject the three calibration gases for each compound in
triplicate and determine the average instrument response. Determine the
CE for each pollutant at each level using the equation in Section 9-2.
Each CE shall be <= 10 percent. Repeat this procedure six more times
for a total of 7 consecutive days.
8.4 Performance Audit Test Periods. Conduct the performance audit
once during the initial 7-day CE test and quarterly thereafter. Sample
and analyze the EPA audit gas(es) (or the gas mixture prepared by EPA's
traceability protocol if an EPA audit gas is not available) three times.
Calculate the average instrument response. Report the audit results as
part of the reporting requirements in the appropriate regulation or
permit (if using a gas mixture, report the certified cylinder
concentration of each pollutant).
8.5 Reporting. Follow the reporting requirements of the applicable
regulation or permit. If the reporting requirements include the results
of this performance specification, summarize in tabular form the results
of the CE tests. Include all data sheets, calculations, CEMS data
records, performance audit results, and calibration gas concentrations
and certifications.

9.0 Quality Control [Reserved]

10.0 Calibration and Standardization

10.1 Initial Multi-Point Calibration. After initial startup of the
GC, after routine maintenance or repair, or at least once per month,
conduct a multi-point calibration of the GC for each target analyte. The
multi-point calibration for each analyte shall meet the requirements in
Section 13.3.
10.2 Daily Calibration. Once every 24 hours, analyze the mid-level
calibration standard for each analyte in triplicate. Calculate the
average instrument response for each analyte. The average instrument
response shall not vary more than 10 percent from the certified
concentration value of the cylinder for each analyte. If the difference
between the analyzer response and the cylinder concentration for any
target compound is greater than 10 percent, immediately inspect the
instrument making any necessary adjustments, and conduct an initial
multi-point calibration as described in Section 10.1.

[[Page 639]]

11.0 Analytical Procedure. Sample Collection and Analysis Are Concurrent
for This Performance Specification (See Section 8.0)

12.0 Calculations and Data Analysis

12.1 Nomenclature.

Cm=average instrument response, ppm.
Ca=cylinder gas value, ppm.
F=Flow rate of stack gas through sampling system, in Liters/min.
n=Number of measurement points.
r²=Coefficient of determination.
V=Sample system volume, in Liters, which is the volume inside the sample
probe and tubing leading from the stack to the sampling loop.
x=CEMS response.
y=Actual value of calibration standard.

12.2 Coefficient of Determination. Calculate r² using
linear regression analysis and the average concentrations obtained at
three calibration points as shown in Equation 9-1.
[GRAPHIC] [TIFF OMITTED] TR17OC00.461

12.3 Calibration Error Determination. Determine the percent
calibration error (CE) at each concentration for each pollutant using
the following equation.
[GRAPHIC] [TIFF OMITTED] TR17OC00.462

12.4 Sampling System Time Constant (T).
[GRAPHIC] [TIFF OMITTED] TR17OC00.463

13.0 Method Performance

13.1 Calibration Error (CE). The CEMS must allow the determination
of CE at all three calibration levels. The average CEMS calibration
response must not differ by more than 10 percent of calibration gas
value at each level after each 24-hour period of the initial test.
13.2 Calibration Precision and Linearity. For each triplicate
injection at each concentration level for each target analyte, any one
injection shall not deviate more than 5 percent from the average
concentration measured at that level. The linear regression curve for
each organic compound at all three levels shall have an r²
=0.995 (using Equation 9-1).
13.3 Measurement Frequency. The sample to be analyzed shall flow
continuously through the sampling system. The sampling system time
constant shall be <=5 minutes or the sampling frequency specified in the
applicable regulation, whichever is less. Use Equation 9-3 to determine
T. The analytical system shall be capable of measuring the effluent
stream at the frequency specified in the appropriate regulation or
permit.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 References [Reserved]

17.0 Tables, Diagrams, Flowcharts, and Validation Data [Reserved]

Performance Specification 11--Specifications and Test Procedures for
Particulate Matter Continuous Emission Monitoring Systems at Stationary
Sources

1.0 What Are the Purpose and Applicability of Performance Specification
11?

The purpose of Performance Specification 11 (PS-11) is to establish
the initial installation and performance procedures that are required
for evaluating the acceptability of a particulate matter (PM) continuous
emission monitoring system (CEMS); it is not to evaluate the ongoing
performance of your PM CEMS over an extended period of time, nor to
identify specific calibration techniques and auxiliary procedures to
assess CEMS performance. You will find procedures for evaluating the
ongoing performance of a PM CEMS in Procedure 2 of Appendix F--Quality
Assurance Requirements for Particulate Matter Continuous Emission
Monitoring Systems Used at Stationary Sources.
1.1 Under what conditions does PS-11 apply to my PM CEMS? The PS-11
applies to your PM CEMS if you are required by any provision of Title 40
of the Code of Federal Regulations (CFR) to install and operate PM CEMS.
1.2 When must I comply with PS-11? You must comply with PS-11 when
directed by the applicable rule that requires you to install and operate
a PM CEMS.
1.3 What other monitoring must I perform? To report your PM
emissions in units of the emission standard, you may need to

[[Page 640]]

monitor additional parameters to correct the PM concentration reported
by your PM CEMS. Your CEMS may include the components listed in
paragraphs (1) through (3) of this section:
(1) A diluent monitor (i.e., O2, CO2, or other
CEMS specified in the applicable regulation), which must meet its own
performance specifications (also found in this appendix),
(2) Auxiliary monitoring equipment to allow measurement,
determination, or input of the flue gas temperature, pressure, moisture
content, and/or dry volume of stack effluent sampled, and
(3) An automatic sampling system. The performance of your PM CEMS
and the establishment of its correlation to manual reference method
measurements must be determined in units of mass concentration as
measured by your PM CEMS (e.g., milligrams per actual cubic meter (mg/
acm) or milligrams per dry standard cubic meter (mg/dscm)).

2.0 What Are the Basic Requirements of PS-11?

The PS-11 requires you to perform initial installation and
calibration procedures that confirm the acceptability of your CEMS when
it is installed and placed into operation. You must develop a site-
specific correlation of your PM CEMS response against manual gravimetric
reference method measurements (including those made using EPA Methods 5,
5I, or 17).
2.1 What types of PM CEMS technologies are covered? Several
different types of PM CEMS technologies (e.g., light scattering, Beta
attenuation, etc.) can be designed with in-situ or extractive sample gas
handling systems. Each PM CEMS technology and sample gas handling
technology has certain site-specific advantages. You should select and
install a PM CEMS that is appropriate for the flue gas conditions at
your source.
2.2 How is PS-11 different from other performance specifications?
The PS-11 is based on a technique of correlating PM CEMS responses
relative to emission concentrations determined by the reference method.
This technique is called ``the correlation.'' This differs from CEMS
used to measure gaseous pollutants that have available calibration gases
of known concentration. Because the type and characteristics of PM vary
from source to source, a single PM correlation, applicable to all
sources, is not possible.
2.3 How are the correlation data handled? You must carefully review
your manual reference method data and your PM CEMS responses to include
only valid, high-quality data. For the correlation, you must convert the
manual reference method data to measurement conditions (e.g., wet or dry
basis) that are consistent with your PM CEMS. Then, you must correlate
the manual method and PM CEMS data in terms of the output as received
from the monitor (e.g., milliamps). At the appropriate PM CEMS response
specified in section 13.2 of this performance specification, you must
calculate the confidence interval half range and tolerance interval half
range as a percentage of the applicable PM concentration emission limit
and compare the confidence interval and tolerance interval percentages
with the performance criteria. Also, you must calculate the correlation
coefficient and compare the correlation coefficient with the applicable
performance criterion specified in section 13.2 of this performance
specification.
Situations may arise where you will need two or more correlations.
If you need multiple correlations, you must collect sufficient data for
each correlation, and each correlation must satisfy the performance
criteria specified in section 13.2 of this performance specification.
2.4 How do I design my PM CEMS correlation program? When planning
your PM CEMS correlation effort, you must address each of the items in
paragraphs (1) through (7) of this section to enhance the probability of
success. You will find each of these elements further described in this
performance specification or in the applicable reference method
procedure.
(1) What type of PM CEMS should I select? You should select a PM
CEMS that is appropriate for your source with technical consideration
for potential factors such as interferences, site-specific
configurations, installation location, flue gas conditions, PM
concentration range, and other PM characteristics. You can find guidance
on which technology is best suited for specific situations in our report
``Current Knowledge of Particulate Matter (PM) Continuous Emission
Monitoring'' (PM CEMS Knowledge Document, see section 16.5).
(2) Where should I install my PM CEMS? Your PM CEMS must be
installed in a location that is most representative of PM emissions, as
determined by the reference method, such that the correlation between PM
CEMS response and emissions determined by the reference method will meet
these performance specifications. Care must be taken in selecting a
location and measurement point to minimize problems due to flow
disturbances, cyclonic flow, and varying PM stratification.
(3) How should I record my CEMS data? You need to ensure that your
PM CEMS and data logger are set up to collect and record all normal
emission levels and excursions. You must ensure that your data logger
and PM CEMS have been properly programmed to accept and transfer status
signals of valid monitor operation (e.g., flags for internal
calibration, suspect data, or maintenance periods).
(4) What CEMS data should I review? You must review drift data daily
to document

[[Page 641]]

proper operation. You must also ensure that any audit material is
appropriate for the typical operating range of your PM CEMS.
(5) How long should I operate my PM CEMS before conducting the
initial correlation test? You should allow sufficient time for your PM
CEMS to operate for you to become familiar with your PM CEMS.
(i) You should observe PM CEMS response over time during normal and
varying process conditions. This will ensure that your PM CEMS has been
properly set up to operate at a range that is compatible with the
concentrations and characteristics of PM emissions for your source. You
should use this information to establish the range of operating
conditions necessary to determine the correlations of PM CEMS data to
manual reference method measurements over a wide operating range.
(ii) You must determine the types of process changes that will
influence, on a definable and repeatable basis, flue gas PM
concentrations and the resulting PM CEMS responses. You may find this
period useful to make adjustments to your planned approach for operating
your PM CEMS at your source. For instance, you may change the
measurement range or batch sampling period to something other than those
you initially planned to use.
(6) How do I conduct the initial correlation test? When conducting
the initial correlation test of your PM CEMS response to PM emissions
determined by the reference method, you must pay close attention to
accuracy and details. Your PM CEMS must be operating properly. You must
perform the manual reference method testing accurately, with attention
to eliminating site-specific systemic errors. You must coordinate the
timing of the manual reference method testing with the sampling cycle of
your PM CEMS. You must complete a minimum of 15 manual reference method
tests. You must perform the manual reference method testing over the
full range of PM CEMS responses that correspond to normal operating
conditions for your source and control device and will result in the
widest range of emission concentrations.
(7) How should I perform the manual reference method testing? You
must perform the manual reference method testing in accordance with
specific rule requirements, coordinated closely with PM CEMS and process
operations. It is highly recommended that you use paired trains for the
manual reference method testing. You must perform the manual reference
method testing over a suitable PM concentration range that corresponds
to the full range of normal process and control device operating
conditions. Because the manual reference method testing for this
correlation test is not for compliance reporting purposes, you may
conduct the reference method test runs for less than the typical minimum
test run duration of 1 hour.
(8) What do I do with the manual reference method data and PM CEMS
data? You must complete each of the activities in paragraphs (8)(i)
through (v) of this section.
(i) Screen the manual reference method data for validity (e.g.,
isokinetics, leak checks), quality assurance, and quality control (e.g.,
outlier identification).
(ii) Screen your PM CEMS data for validity (e.g., daily drift check
requirements) and quality assurance (e.g., flagged data).
(iii) Convert the manual reference method test data into measurement
units (e.g., mg/acm) consistent with the measurement conditions of your
PM CEMS.
(iv) Calculate the correlation equation(s) as specified in section
12.3.
(v) Calculate the correlation coefficient, confidence interval half
range, and tolerance interval half range for the complete set of PM CEMS
and reference method correlation data for comparison with the
correlation performance criteria specified in section 13.2.
2.5 What other procedures must I perform? Before conducting the
initial correlation test, you must successfully complete a 7-day drift
test (See section 8.5).

3.0 What Special Definitions Apply to PS-11?

3.1 ``Appropriate Measurement Range of your PM CEMS'' means a
measurement range that is capable of recording readings over the
complete range of your source's PM emission concentrations during
routine operations. The appropriate range is determined during the
pretest preparations as specified in section 8.4.
3.2 ``Appropriate Data Range for PM CEMS Correlation'' means the
data range that reflects the full range of your source's PM emission
concentrations recorded by your PM CEMS during the correlation test
planning period or other normal operations as defined in the applicable
regulations.
3.3 ``Batch Sampling'' means that gas is sampled on an intermittent
basis and concentrated on a collection medium before intermittent
analysis and follow-up reporting. Beta gauge PM CEMS are an example of
batch sampling devices.
3.4 ``Confidence Interval Half Range (CI)'' means the statistical
term for one-half of the width of the 95 percent confidence interval
around the predicated mean PM concentration (y value) calculated at the
PM CEMS response value (x value) where the confidence interval is
narrowest. Procedures for calculating CI are specified in section
12.3(1)(ii) for linear correlations and in section 12.3(2)(ii) for
polynomial correlations. The CI as a percent of the emission limit value
(CI%) is calculated at the appropriate PM CEMS response value specified
in Section 13.2(2).

[[Page 642]]

3.5 ``Continuous Emission Monitoring System (CEMS)'' means all of
the equipment required for determination of PM mass concentration in
units of the emission standard. The sample interface, pollutant monitor,
diluent monitor, other auxiliary data monitor(s), and data recorder are
the major subsystems of your CEMS.
3.6 ``Correlation'' means the primary mathematical relationship for
correlating the output from your PM CEMS to a PM concentration, as
determined by the PM reference method. The correlation is expressed in
the measurement units that are consistent with the measurement
conditions (e.g., mg/dscm, mg/acm) of your PM CEMS.
3.7 ``Correlation Coefficient (r)'' means a quantitative measure of
the association between your PM CEMS outputs and the reference method
measurements. Equations for calculating the r value are provided in
section 12.3(1)(iv) for linear correlations and in section 12.3(2)(iv)
for polynomial correlations.
3.8 ``Cycle Time'' means the time required to complete one sampling,
measurement, and reporting cycle. For a batch sampling PM CEMS, the
cycle time would start when sample gas is first extracted from the
stack/duct and end when the measurement of that batch sample is complete
and a new result for that batch sample is produced on the data recorder.
3.9 ``Data Recorder'' means the portion of your CEMS that provides a
permanent record of the monitor output in terms of response and status
(flags). The data recorder may also provide automatic data reduction and
CEMS control capabilities (see section 6.6).
3.10 ``Diluent Monitor and Other Auxiliary Data Monitor(s) (if
applicable)'' means the portion of your CEMS that provides the diluent
gas concentration (such as O2 or CO2, as specified
by the applicable regulations), temperature, pressure, and/or moisture
content, and generates an output proportional to the diluent gas
concentration or gas property.
3.11 ``Drift Check'' means a check of the difference between your PM
CEMS output readings and the established reference value of a reference
standard or procedure after a stated period of operation during which no
unscheduled maintenance, repair, or adjustment took place. The
procedures used to determine drift are specific to the operating
principles of your specific PM CEMS. A drift check includes both a zero
drift check and an upscale drift check.
3.12 ``Exponential Correlation'' means an exponential equation used
to define the relationship between your PM CEMS output and the reference
method PM concentration, as indicated by Equation 11-37.
3.13 ``Flagged Data'' means data marked by your CEMS indicating that
the response value(s) from one or more CEMS subsystems is suspect or
invalid or that your PM CEMS is not in source-measurement operating
mode.
3.14 ``Linear Correlation'' means a first-order mathematical
relationship between your PM CEMS output and the reference method PM
concentration that is linear in form, as indicated by Equation 11-3.
3.15 ``Logarithmic Correlation'' means a first-order mathematical
relationship between the natural logarithm of your PM CEMS output and
the reference method PM concentration that is linear in form, as
indicated by Equation 11-34.
3.16 ``Low-Emitting Source'' means a source that operated at no more
than 50 percent of the emission limit during the most recent performance
test, and, based on the PM CEMS correlation, the daily average emissions
for the source, measured in the units of the applicable emission limit,
have not exceeded 50 percent of the emission limit for any day since the
most recent performance test.
3.17 ``Paired Trains'' means two reference method trains that are
used to conduct simultaneous measurements of PM concentrations. Guidance
on the use of paired sampling trains can be found in the PM CEMS
Knowledge Document (see section 16.5).
3.18 ``Polynomial Correlation'' means a second-order equation used
to define the relationship between your PM CEMS output and reference
method PM concentration, as indicated by Equation 11-16.
3.19 ``Power Correlation'' means an equation used to define a power
function relationship between your PM CEMS output and the reference
method concentration, as indicated by Equation 11-42.
3.20 ``Reference Method'' means the method defined in the applicable
regulations, but commonly refers to those methods collectively known as
EPA Methods 5, 5I, and 17 (for particulate matter), found in Appendix A
of 40 CFR 60. Only the front half and dry filter catch portions of the
reference method can be correlated to your PM CEMS output.
3.21 ``Reference Standard'' means a reference material or procedure
that produces a known and unchanging response when presented to the
pollutant monitor portion of your CEMS. You must use these standards to
evaluate the overall operation of your PM CEMS, but not to develop a PM
CEMS correlation.
3.22 ``Response Time'' means the time interval between the start of
a step change in the system input and the time when the pollutant
monitor output reaches 95 percent of the final value (see sections 6.5
and 13.3 for procedures and acceptance criteria).
3.23 ``Sample Interface'' means the portion of your CEMS used for
one or more of the following: sample acquisition, sample delivery,
sample conditioning, or protection of

[[Page 643]]

the monitor from the effects of the stack effluent.
3.24 ``Sample Volume Check'' means a check of the difference between
your PM CEMS sample volume reading and the sample volume reference
value.
3.25 ``Tolerance Interval half range (TI)'' means one-half of the
width of the tolerance interval with upper and lower limits, within
which a specified percentage of the future data population is contained
with a given level of confidence, as defined by the respective tolerance
interval half range equations in section 12.3(1)(iii) for linear
correlations and in section 12.3(2)(iii) for polynomial correlations.
The TI as a percent of the emission limit value (TI%) is calculated at
the appropriate PM CEMS response value specified in Section 13.2(3).
3.26 ``Upscale Check Value'' means the expected response to a
reference standard or procedure used to check the upscale response of
your PM CEMS.
3.27 ``Upscale Drift (UD) Check'' means a check of the difference
between your PM CEMS output reading and the upscale check value.
3.28 ``Zero Check Value'' means the expected response to a reference
standard or procedure used to check the response of your PM CEMS to
particulate-free or low-particulate concentration conditions.
3.29 ``Zero Drift (ZD) Check'' means a check of the difference
between your PM CEMS output reading and the zero check value.
3.30 ``Zero Point Correlation Value'' means a value added to PM CEMS
correlation data to represent low or near zero PM concentration data
(see section 8.6 for rationale and procedures).

4.0 Are There Any Potential Interferences for My PM CEMS?

Yes, condensible water droplets or condensible acid gas aerosols
(i.e., those with condensation temperatures above those specified by the
reference method) at the measurement location can be interferences for
your PM CEMS if the necessary precautions are not met.
4.1 Where are interferences likely to occur? Interferences may
develop if your CEMS is installed downstream of a wet air pollution
control system or any other conditions that produce flue gases, which,
at your PM CEMS measurement point, normally or occasionally contain
entrained water droplets or condensible salts before release to the
atmosphere.
4.2 How do I deal with interferences? We recommend that you use a PM
CEMS that extracts and heats representative samples of the flue gas for
measurement to simulate results produced by the reference method for
conditions such as those described in section 4.1. Independent of your
PM CEMS measurement technology and extractive technique, you should have
a configuration simulating the reference method to ensure that:
(1) No formation of new PM or deposition of PM occurs in sample
delivery from the stack or duct; and
(2) No condensate accumulates in the sample flow measurement
apparatus.
4.3 What PM CEMS measurement technologies should I use? You should
use a PM CEMS measurement technology that is free of interferences from
any condensible constituent in the flue gas.

5.0 What Do I Need To Know To Ensure the Safety of Persons Using PS-11?

People using the procedures required under PS-11 may be exposed to
hazardous materials, operations, site conditions, and equipment. This
performance specification does not purport to address all of the safety
issues associated with its use. It is your responsibility to establish
appropriate safety and health practices and determine the applicable
regulatory limitations before performing these procedures. You must
consult your CEMS user's manual and other reference materials
recommended by the reference method for specific precautions to be
taken.

6.0 What Equipment and Supplies Do I Need?

Different types of PM CEMS use different operating principles. You
should select an appropriate PM CEMS based on your site-specific
configurations, flue gas conditions, and PM characteristics.
(1) Your PM CEMS must sample the stack effluent continuously or, for
batch sampling PM CEMS, intermittently.
(2) You must ensure that the averaging time, the number of
measurements in an average, the minimum data availability, and the
averaging procedure for your CEMS conform with those specified in the
applicable emission regulation.
(3) Your PM CEMS must include, as a minimum, the equipment described
in sections 6.1 through 6.7.
6.1 What equipment is needed for my PM CEMS's sample interface? Your
PM CEMS's sample interface must be capable of delivering a
representative sample of the flue gas to your PM CEMS. This subsystem
may be required to heat the sample gas to avoid PM deposition or
moisture condensation, provide dilution air, perform other gas
conditioning to prepare the sample for analysis, or measure the sample
volume or flow rate.
(1) If your PM CEMS is installed downstream of a wet air pollution
control system such that the flue gases normally or occasionally contain
entrained water droplets, we recommend that you select a sampling system
that includes equipment to extract and heat a representative sample of
the flue gas for measurement so that the pollutant

[[Page 644]]

monitor portion of your CEMS measures only dry PM. Heating should be
sufficient to raise the temperature of the extracted flue gas above the
water condensation temperature and should be maintained at all times and
at all points in the sample line from where the flue gas is extracted,
including the pollutant monitor and any sample flow measurement devices.
(2) You must consider the measured conditions of the sample gas
stream to ensure that manual reference method test data are converted to
units of PM concentration that are appropriate for the correlation
calculations. Additionally, you must identify what, if any, additional
auxiliary data from other monitoring and handling systems are necessary
to convert your PM CEMS response into the units of the PM standard.
(3) If your PM CEMS is an extractive type and your source's flue gas
volumetric flow rate varies by more than 10 percent from nominal, your
PM CEMS should maintain an isokinetic sampling rate (within 10 percent
of true isokinetic). If your extractive-type PM CEMS does not maintain
an isokinetic sampling rate, you must use actual site-specific data or
data from a similar installation to prove to us, the State, and/or local
enforcement agency that isokinetic sampling is not necessary.
6.2 What type of equipment is needed for my PM CEMS? Your PM CEMS
must be capable of providing an electronic output that can be correlated
to the PM concentration.
(1) Your PM CEMS must be able to perform zero and upscale drift
checks. You may perform these checks manually, but performing these
checks automatically is preferred.
(2) We recommend that you select a PM CEMS that is capable of
performing automatic diagnostic checks and sending instrument status
signals (flags) to the data recorder.
(3) If your PM CEMS is an extractive type that measures the sample
volume and uses the measured sample volume as part of calculating the
output value, your PM CEMS must be able to perform a check of the sample
volume to verify the accuracy of the sample volume measuring equipment.
The sample volume check must be conducted daily and at the normal
sampling rate of your PM CEMS.
6.3 What is the appropriate measurement range for my PM CEMS?
Initially, your PM CEMS must be set up to measure over the expected
range of your source's PM emission concentrations during routine
operations. You may change the measurement range to a more appropriate
range prior to correlation testing.
6.4 What if my PM CEMS does automatic range switching? Your PM CEMS
may be equipped to perform automatic range switching so that it is
operating in a range most sensitive to the detected concentrations. If
your PM CEMS does automatic range switching, you must configure the data
recorder to handle the recording of data values in multiple ranges
during range-switching intervals.
6.5 What averaging time and sample intervals should be used? Your
CEMS must sample the stack effluent such that the averaging time, the
number of measurements in an average, the minimum sampling time, and the
averaging procedure for reporting and determining compliance conform
with those specified in the applicable regulation. Your PM CEMS must be
designed to meet the specified response time and cycle time established
in this performance specification (see section 13.3).
6.6 What type of equipment is needed for my data recorder? Your CEMS
data recorder must be able to accept and record electronic signals from
all the monitors associated with your PM CEMS.
(1) Your data recorder must record the signals from your PM CEMS
that can be correlated to PM mass concentrations. If your PM CEMS uses
multiple ranges, your data recorder must identify what range the
measurement was made in and provide range-adjusted results.
(2) Your data recorder must accept and record monitor status signals
(flagged data).
(3) Your data recorder must accept signals from auxiliary data
monitors, as appropriate.
6.7 What other equipment and supplies might I need? You may need
other supporting equipment as defined by the applicable reference
method(s) (see section 7) or as specified by your CEMS manufacturer.

7.0 What Reagents and Standards Do I Need?

You will need reference standards or procedures to perform the zero
drift check, the upscale drift check, and the sample volume check.
7.1 What is the reference standard value for the zero drift check?
You must use a zero check value that is no greater than 20 percent of
the PM CEMS's response range. You must obtain documentation on the zero
check value from your PM CEMS manufacturer.
7.2 What is the reference standard value for the upscale drift
check? You must use an upscale check value that produces a response
between 50 and 100 percent of the PM CEMS's response range. For a PM
CEMS that produces output over a range of 4 mA to 20 mA, the upscale
check value must produce a response in the range of 12 mA to 20 mA. You
must obtain documentation on the upscale check value from your PM CEMS
manufacturer.
7.3 What is the reference standard value for the sample volume
check? You must use a reference standard value or procedure that
produces a sample volume value equivalent

[[Page 645]]

to the normal sampling rate. You must obtain documentation on the sample
volume value from your PM CEMS manufacturer.

8.0 What Performance Specification Test Procedure Do I Follow?

You must complete each of the activities in sections 8.1 through 8.8
for your performance specification test.
8.1 How should I select and set up my equipment? You should select a
PM CEMS that is appropriate for your source, giving consideration to
potential factors such as flue gas conditions, interferences, site-
specific configuration, installation location, PM concentration range,
and other PM characteristics. Your PM CEMS must meet the equipment
specifications in sections 6.1 and 6.2.
(1) You should select a PM CEMS that is appropriate for the flue gas
conditions at your source. If your source's flue gas contains entrained
water droplets, we recommend that your PM CEMS include a sample delivery
and conditioning system that is capable of extracting and heating a
representative sample.
(i) Your PM CEMS must maintain the sample at a temperature
sufficient to prevent moisture condensation in the sample line before
analysis of PM.
(ii) If condensible PM is an issue, we recommend that you operate
your PM CEMS to maintain the sample gas temperature at the same
temperature as the reference method filter.
(iii) Your PM CEMS must avoid condensation in the sample flow rate
measurement lines.
(2) Some PM CEMS do not have a wide measurement range capability.
Therefore, you must select a PM CEMS that is capable of measuring the
full range of PM concentrations expected from your source from normal
levels through the emission limit concentration.
(3) Some PM CEMS are sensitive to particle size changes, water
droplets in the gas stream, particle charge, stack gas velocity changes,
or other factors. Therefore, you should select a PM CEMS appropriate for
the emission characteristics of your source.
(4) We recommend that you consult your PM CEMS vendor to obtain
basic recommendations on the instrument capabilities and setup
configuration. You are ultimately responsible for setup and operation of
your PM CEMS.
8.2 Where do I install my PM CEMS? You must install your PM CEMS at
an accessible location downstream of all pollution control equipment.
You must perform your PM CEMS concentration measurements from a location
considered representative or be able to provide data that can be
corrected to be representative of the total PM emissions as determined
by the manual reference method.
(1) You must select a measurement location that minimizes problems
due to flow disturbances, cyclonic flow, and varying PM stratification
(refer to Method 1 for guidance).
(2) If you plan to achieve higher emissions for correlation test
purposes by adjusting the performance of the air pollution control
device (per section 8.6(4)(i)), you must locate your PM CEMS and
reference method sampling points well downstream of the control device
(e.g., downstream of the induced draft fan), in order to minimize PM
stratification that may be created in these cases.
8.3 How do I select the reference method measurement location and
traverse points? You must follow EPA Method 1 for identifying manual
reference method traverse points. Ideally, you should perform your
manual reference method measurements at locations that satisfy the
measurement site selection criteria specified in EPA Method 1 of at
least eight duct diameters downstream and at least two duct diameters
upstream of any flow disturbance. Where necessary, you may conduct
testing at a location that is two diameters downstream and 0.5 diameters
upstream of flow disturbances. If your location does not meet the
minimum downstream and upstream requirements, you must obtain approval
from us to test at your location.
8.4 What are my pretest preparation steps? You must install your
CEMS and prepare the reference method test site according to the
specifications in sections 8.2 and 8.3.
(1) After completing the initial field installation, we recommend
that you operate your PM CEMS according to the manufacturer's
instructions to familiarize yourself with its operation before you begin
correlation testing.
(i) During this initial period of operation, we recommend that you
conduct daily checks (zero and upscale drift and sample volume, as
appropriate), and, when any check exceeds the daily specification (see
section 13.1), make adjustments and perform any necessary maintenance to
ensure reliable operation.
(2) When you are confident that your PM CEMS is operating properly,
we recommend that you operate your CEMS over a correlation test planning
period of sufficient duration to identify the full range of operating
conditions and PM emissions to be used in your PM CEMS correlation test.
(i) During the correlation test planning period, you should operate
the process and air pollution control equipment over the normal range of
operating conditions, except when you attempt to produce higher
emissions.
(ii) Your data recorder should record PM CEMS response during the
full range of routine process operating conditions.

[[Page 646]]

(iii) You should try to establish the relationships between
operating conditions and PM CEMS response, especially those conditions
that produce the highest PM CEMS response over 15-minute averaging
periods, and the lowest PM CEMS response as well. The objective is to be
able to reproduce the conditions for purposes of the actual correlation
testing discussed in section 8.6.
(3) You must set the response range of your PM CEMS such that the
instrument measures the full range of responses that correspond to the
range of source operating conditions that you will implement during
correlation testing.
(4) We recommend that you perform preliminary reference method
testing after the correlation test planning period. During this
preliminary testing, you should measure the PM emission concentration
corresponding to the highest PM CEMS response observed during the full
range of normal operation, when perturbing the control equipment, or as
the result of PM spiking.
(5) Before performing correlation testing, you must perform a 7-day
zero and upscale drift test (see section 8.5).
(6) You must not change the response range of the monitor once the
response range has been set and the drift test successfully completed.
8.5 How do I perform the 7-day drift test? You must check the zero
(or low-level value between 0 and 20 percent of the response range of
the instrument) and upscale (between 50 and 100 percent of the
instrument's response range) drift. You must perform this check at least
once daily over 7 consecutive days. Your PM CEMS must quantify and
record the zero and upscale measurements and the time of the
measurements. If you make automatic or manual adjustments to your PM
CEMS zero and upscale settings, you must conduct the drift test
immediately before these adjustments, or conduct it in such a way that
you can determine the amount of drift. You will find the calculation
procedures for drift in section 12.1 and the acceptance criteria for
allowable drift in section 13.1.
(1) What is the purpose of 7-day drift tests? The purpose of the 7-
day drift test is to demonstrate that your system is capable of
operating in a stable manner and maintaining its calibration for at
least a 7-day period.
(2) How do I conduct the 7-day drift test? To conduct the 7-day
drift test, you must determine the magnitude of the drift once each day,
at 24-hour intervals, for 7 consecutive days while your source is
operating normally.
(i) You must conduct the 7-day drift test at the two points
specified in section 8.5. You may perform the 7-day drift tests
automatically or manually by introducing to your PM CEMS suitable
reference standards (these need not be certified) or by using other
appropriate procedures.
(ii) You must record your PM CEMS zero and upscale response and
evaluate them against the zero check value and upscale check value.
(3) When must I conduct the 7-day drift test? You must complete a
valid 7-day drift test before attempting the correlation test.
8.6 How do I conduct my PM CEMS correlation test? You must conduct
the correlation test according to the procedure given in paragraphs (1)
through (5) of this section. If you need multiple correlations, you must
conduct sufficient testing and collect at least 15 pairs of reference
method and PM CEMS data for calculating each separate correlation.
(1) You must use the reference method for PM (usually EPA Methods 5,
5I, or 17) that is prescribed by the applicable regulations. You may
need to perform other reference methods or performance specifications
(e.g., Method 3 for oxygen, Method 4 for moisture, etc.) depending on
the units in which your PM CEMS reports PM concentration.
(i) We recommend that you use paired reference method trains when
collecting manual PM data to identify and screen the reference method
data for imprecision and bias. Procedures for checking reference method
data for bias and precision can be found in the PM CEMS Knowledge
Document (see section 16.5).
(ii) You may use test runs that are shorter than 60 minutes in
duration (e.g., 20 or 30 minutes). You may perform your PM CEMS
correlation tests during new source performance standards performance
tests or other compliance tests subject to the Clean Air Act or other
statutes, such as the Resource Conservation and Recovery Act. In these
cases, your reference method results obtained during the PM CEMS
correlation test may be used to determine compliance so long as your
source and the test conditions and procedures (e.g., reference method
sample run durations) are consistent with the applicable regulations and
the reference method.
(iii) You must convert the reference method results to units
consistent with the conditions of your PM CEMS measurements. For
example, if your PM CEMS measures and reports PM emissions in the units
of mass per actual volume of stack gas, you must convert your reference
method results to those units (e.g., mg/acm). If your PM CEMS extracts
and heats the sample gas to eliminate water droplets, then measures and
reports PM emissions under those actual conditions, you must convert
your reference method results to those same conditions (e.g., mg/acm at
160 [deg]C).
(2) During each test run, you must coordinate process operations,
reference method

[[Page 647]]

sampling, and PM CEMS operations. For example, you must ensure that the
process is operating at the targeted conditions, both reference method
trains are sampling simultaneously (if paired sampling trains are being
used), and your PM CEMS and data logger are operating properly.
(i) You must coordinate the start and stop times of each run between
the reference method sampling and PM CEMS operation. For a batch
sampling PM CEMS, you must start the reference method at the same time
as your PM CEMS sampling.
(ii) You must note the times for port changes (and other periods
when the reference method sampling may be suspended) on the data sheets
so that you can adjust your PM CEMS data accordingly, if necessary.
(iii) You must properly align the time periods for your PM CEMS and
your reference method measurements to account for your PM CEMS response
time.
(3) You must conduct a minimum of 15 valid runs each consisting of
simultaneous PM CEMS and reference method measurement sets.
(i) You may conduct more than 15 sets of CEMS and reference method
measurements. If you choose this option, you may reject certain test
results so long as the total number of valid test results you use to
determine the correlation is greater than or equal to 15.
(ii) You must report all data, including the rejected data.
(iii) You may reject the results of up to five test runs without
explanation.
(iv) If you reject the results of more than five test runs, the
basis for rejecting the results of the additional test runs must be
explicitly stated in the reference method, this performance
specification, Procedure 2 of appendix F, or your quality assurance
plan.
(4) Simultaneous PM CEMS and reference method measurements must be
performed in a manner to ensure that the range of data that will be used
to establish the correlation for your PM CEMS is maximized. You must
first attempt to maximize your correlation range by following the
procedures described in paragraphs (4)(i) through (iv) of this section.
If you cannot obtain the three levels as described in paragraphs (i)
through (iv), then you must use the procedure described in section
8.6(5).
(i) You must attempt to obtain the three different levels of PM mass
concentration by varying process operating conditions, varying PM
control device conditions, or by means of PM spiking.
(ii) The three PM concentration levels you use in the correlation
tests must be distributed over the complete operating range experienced
by your source.
(iii) At least 20 percent of the minimum 15 measured data points you
use should be contained in each of the following levels:
Level 1: From no PM (zero concentration)
emissions to 50 percent of the maximum PM concentration;
Level 2: 25 to 75 percent of the maximum PM
concentration; and
Level 3: 50 to 100 percent of the maximum PM
concentration.
(iv) Although the above levels overlap, you may only apply
individual run data to one level.
(5) If you cannot obtain three distinct levels of PM concentration
as described, you must perform correlation testing over the maximum
range of PM concentrations that is practical for your PM CEMS. To ensure
that the range of data used to establish the correlation for your PM
CEMS is maximized, you must follow one or more of the steps in
paragraphs (5)(i) through (iv) of this section.
(i) Zero point data for in-situ instruments should be obtained, to
the extent possible, by removing the instrument from the stack and
monitoring ambient air on a test bench.
(ii) Zero point data for extractive instruments should be obtained
by removing the extractive probe from the stack and drawing in clean
ambient air.
(iii) Zero point data also can be obtained by performing manual
reference method measurements when the flue gas is free of PM emissions
or contains very low PM concentrations (e.g., when your process is not
operating, but the fans are operating or your source is combusting only
natural gas).
(iv) If none of the steps in paragraphs (5)(i) through (iii) of this
section are possible, you must estimate the monitor response when no PM
is in the flue gas (e.g., 4 mA = 0 mg/acm).
8.7 What do I do with the initial correlation test data for my PM
CEMS? You must calculate and report the results of the correlation
testing, including the correlation coefficient, confidence interval, and
tolerance interval for the PM CEMS response and reference method
correlation data that are use to establish the correlation, as specified
in section 12. You must include all data sheets, calculations, charts
(records of PM CEMS responses), process data records including PM
control equipment operating parameters, and reference media
certifications necessary to confirm that your PM CEMS met the
requirements of this performance specification. In addition, you must:
(1) Determine the integrated (arithmetic average) PM CEMS output
over each reference method test period;
(2) Adjust your PM CEMS outputs and reference method test data to
the same clock time (considering response time of your PM CEMS);
(3) Confirm that the reference method results are consistent with
your PM CEMS response in terms of, where applicable, moisture,
temperature, pressure, and diluent concentrations; and

[[Page 648]]

(4) Determine whether any of the reference method test results do
not meet the test method criteria.
8.8 What is the limitation on the range of my PM CEMS correlation?
Although the data you collect during the correlation testing should be
representative of the full range of normal operating conditions at your
source, you must conduct additional correlation testing if either of the
conditions specified in paragraphs (1) and (2) of this section occurs.
(1) If your source is a low-emitting source, as defined in section
3.16 of this specification, you must conduct additional correlation
testing if either of the events specified in paragraphs (1)(i) or (ii)
of this section occurs while your source is operating under normal
conditions.
(i) Your source generates 24 consecutive hourly average PM CEMS
responses that are greater than 125 percent of the highest PM CEMS
response (e.g., mA reading) used for the correlation curve or are
greater than the PM CEMS response that corresponds to 50 percent of the
emission limit, whichever is greater, or
(ii) The cumulative hourly average PM CEMS responses generated by
your source are greater than 125 percent of the highest PM CEMS response
used for the correlation curve or are greater than the PM CEMS response
that corresponds to 50 percent of the emission limit, whichever is
greater, for more than 5 percent of your PM CEMS operating hours for the
previous 30-day period.
(2) If your source is not a low-emitting source, as defined in
section 3.16 of this specification, you must conduct additional
correlation testing if either of the events specified in paragraph (i)
or (ii) of this section occurs while your source is operating under
normal conditions.
(i) Your source generates 24 consecutive hourly average PM CEMS
responses that are greater than 125 percent of the highest PM CEMS
response (e.g., mA reading) used for the correlation curve, or
(ii) The cumulative hourly average PM CEMS responses generated by
your source are greater than 125 percent of the highest PM CEMS response
used for the correlation curve for more than 5 percent of your PM CEMS
operating hours for the previous 30-day period.
(3) If additional correlation testing is required, you must conduct
at least three additional test runs under the conditions that caused the
higher PM CEMS response.
(i) You must complete the additional testing and use the resulting
new data along with the previous data to calculate a revised correlation
equation within 60 days after the occurrence of the event that requires
additional testing, as specified in paragraphs 8.8(1) and (2).
(4) If your source generates consecutive PM CEMS hourly responses
that are greater than 125 percent of the highest PM CEMS response used
to develop the correlation curve for 24 hours or for a cumulative period
that amounts to more than 5 percent of the PM CEMS operating hours for
the previous 30-day period, you must report the reason for the higher PM
CEMS responses.

9.0 What Quality Control Measures Are Required?

Quality control measures for PM CEMS are specified in 40 CFR 60,
Appendix F, Procedure 2.

10.0 What Calibration and Standardization Procedures Must I Perform?
[Reserved]

11.0 What Analytical Procedures Apply to This Procedure?

Specific analytical procedures are outlined in the applicable
reference method(s).

12.0 What Calculations and Data Analyses Are Needed?

You must determine the primary relationship for correlating the
output from your PM CEMS to a PM concentration, typically in units of
mg/acm or mg/dscm of flue gas, using the calculations and data analysis
process in sections 12.2 and 12.3. You develop the correlation by
performing an appropriate regression analysis between your PM CEMS
response and your reference method data.
12.1 How do I calculate upscale drift and zero drift? You must
determine the difference in your PM CEMS output readings from the
established reference values (zero and upscale check values) after a
stated period of operation during which you performed no unscheduled
maintenance, repair, or adjustment.
(1) Calculate the upscale drift (UD) using Equation 11-1:
[GRAPHIC] [TIFF OMITTED] TR12JA04.003

Where:

UD = The upscale (high-level) drift of your PM CEMS in percent,
RCEM = The measured PM CEMS response to the upscale reference
standard, and
RU = The preestablished numerical value of the upscale
reference standard.

(2) Calculate the zero drift (ZD) using Equation 11-2:
[GRAPHIC] [TIFF OMITTED] TR12JA04.004

Where:

[[Page 649]]

ZD = The zero (low-level) drift of your PM CEMS in percent,
RCEM = The measured PM CEMS response to the zero reference
standard,
RL = The preestablished numerical value of the zero reference
standard, and
RU = The preestablished numerical value of the upscale
reference standard.

(3) Summarize the results on a data sheet similar to that shown in
Table 2 (see section 17).
12.2 How do I perform the regression analysis? You must couple each
reference method PM concentration measurement, y, in the appropriate
units, with an average PM CEMS response, x, over corresponding time
periods. You must complete your PM CEMS correlation calculations using
data deemed acceptable by quality control procedures identified in 40
CFR 60, Appendix F, Procedure 2.
(1) You must evaluate all flagged or suspect data produced during
measurement periods and determine whether they should be excluded from
your PM CEMS's average.
(2) You must assure that the reference method and PM CEMS results
are on a consistent moisture, temperature, and diluent basis. You must
convert the reference method PM concentration measurements (dry standard
conditions) to the units of your PM CEMS measurement conditions. The
conditions of your PM CEMS measurement are monitor-specific. You must
obtain from your PM CEMS vendor or instrument manufacturer the
conditions and units of measurement for your PM CEMS.
(i) If your sample gas contains entrained water droplets and your PM
CEMS is an extractive system that measures at actual conditions (i.e.,
wet basis), you must use the measured moisture content determined from
the impinger analysis when converting your reference method PM data to
PM CEMS conditions; do not use the moisture content calculated from a
psychrometric chart based on saturated conditions.
12.3 How do I determine my PM CEMS correlation? To predict PM
concentrations from PM CEMS responses, you must use the calculation
method of least squares presented in paragraphs (1) through (5) of this
section. When performing the calculations, each reference method PM
concentration measurement must be treated as a discrete data point; if
using paired sampling trains, do not average reference method data pairs
for any test run.
This performance specification describes procedures for evaluating
five types of correlation models: linear, polynomial, logarithmic,
exponential, and power. Procedures for selecting the most appropriate
correlation model are presented in section 12.4 of this specification.
(1) How do I evaluate a linear correlation for my correlation test
data? To evaluate a linear correlation, follow the procedures described
in paragraphs (1)(i) through (iv) of this section.
(i) Calculate the linear correlation equation, which gives the
predicted PM concentration () as a function of the PM CEMS response (x),
as indicated by Equation 11-3:
[GRAPHIC] [TIFF OMITTED] TR12JA04.005

Where:

y = the predicted PM concentration,
b0 = the intercept for the correlation curve, as calculated
using Equation 11-4,
b1 = the slope of the correlation curve, as calculated using
Equation 11-6, and
x = the PM CEMS response value.

Calculate the y intercept (b0) of the correlation curve
using Equation 11-4:
[GRAPHIC] [TIFF OMITTED] TR12JA04.006

Where:

x = the mean value of the PM CEMS response data, as calculated using
Equation 11-5, and
y = the mean value of the PM concentration data, as calculated using
Equation 11-5:
[GRAPHIC] [TIFF OMITTED] TR12JA04.007

Where:

xi = the PM CEMS response value for run i,
yi = the PM concentration value for run i, and
n = the number of data points.

Calculate the slope (b1) of the correlation curve using
Equation 11-6:
[GRAPHIC] [TIFF OMITTED] TR12JA04.008

Where:

Sxx, Sxy = as calculated using Equation 11-7:
[GRAPHIC] [TIFF OMITTED] TR12JA04.009

[[Page 650]]

(ii) Calculate the half range of the 95 percent confidence interval
(CI) for the predicted PM concentration (y) at the mean value of x,
using Equation 11-8:
[GRAPHIC] [TIFF OMITTED] TR12JA04.010

Where:

CI = the half range for the 95 percent confidence interval for the mean
x value,
tdf,1-a/2 = the value for the t statistic provided in Table 1
for df = n-2, and
SL = the scatter or deviation of values about the correlation
curve, which is determined using Equation 11-9:
[GRAPHIC] [TIFF OMITTED] TR12JA04.011

Calculate the confidence interval half range at the mean x value as
a percentage of the emission limit (CI%) using Equation 11-10:
[GRAPHIC] [TIFF OMITTED] TR12JA04.012

Where:

CI = the confidence interval half range at the mean x value, and
EL = PM emission limit, as described in section 13.2.

(iii) Calculate the half range of the tolerance interval at the mean
x value (TI) using Equation 11-11:
[GRAPHIC] [TIFF OMITTED] TR12JA04.013

Where:

TI = the tolerance interval half range at the mean x value,
kt = as calculated using Equation 11-12, and
SL = as calculated using Equation 11-9:
[GRAPHIC] [TIFF OMITTED] TR12JA04.014

Where:

n[min] = the number of test runs (n),
un[min] = the tolerance factor for 75 percent provided in
Table 1, and
vdf = the value from Table 1 for df = n-2.
Calculate the tolerance interval half range at the mean x value as a
percentage of the emission limit (TI%) using Equation 11-13:
[GRAPHIC] [TIFF OMITTED] TR12JA04.015

Where:

TI = the tolerance interval half range at the mean value of x, and
EL = PM emission limit, as described in section 13.2.

(iv) Calculate the linear correlation coefficient (r) using Equation
11-14:
[GRAPHIC] [TIFF OMITTED] TR12JA04.016

Where:

SL = as calculated using Equation 11-9, and
Sy = as calculated using Equation 11-15:
[GRAPHIC] [TIFF OMITTED] TR12JA04.017

(2) How do I evaluate a polynomial correlation for my correlation
test data? To evaluate a polynomial correlation, follow the procedures
described in paragraphs (2)(i) through (iv) of this section.
(i) Calculate the polynomial correlation equation, which is
indicated by Equation 11-16, using Equations 11-17 through 11-22:
[GRAPHIC] [TIFF OMITTED] TR12JA04.018

Where:

y = the PM CEMS concentration predicted by the polynomial correlation
equation, and
b0, b1, b2 = the coefficients
determined from the solution to the matrix equation Ab=B where:
[GRAPHIC] [TIFF OMITTED] TR12JA04.019

[[Page 651]]

[GRAPHIC] [TIFF OMITTED] TR12JA04.020

Where:

xi = the PM CEMS response for run i,
yi = the reference method PM concentration for run i, and
n = the number of test runs.

Calculate the polynomial correlation curve coefficients
(b0, b1, and b2) using Equations 11-19
to 11-21, respectively:
[GRAPHIC] [TIFF OMITTED] TR12JA04.021

[GRAPHIC] [TIFF OMITTED] TR12JA04.022

Where:
[GRAPHIC] [TIFF OMITTED] TR12JA04.023

(ii) Calculate the confidence interval half range (CI) by first
calculating the C coefficients (C0 to C5) using
Equations 11-23 and 11-24:
Where:
[GRAPHIC] [TIFF OMITTED] TR12JA04.024

Where:
[GRAPHIC] [TIFF OMITTED] TR12JA04.025

Calculate [Delta] using Equation 11-25 for each x value:
[GRAPHIC] [TIFF OMITTED] TR12JA04.026

[[Page 652]]

Determine the x value that corresponds to the minimum value of
[Delta] ([Delta]min). Determine the scatter or deviation of
values about the polynomial correlation curve (SP) using
Equation 11-26:
[GRAPHIC] [TIFF OMITTED] TR12JA04.027

Calculate the half range of the 95 percent confidence interval (CI)
at the x value that corresponds to [Delta]min using Equation
11-27:
[GRAPHIC] [TIFF OMITTED] TR12JA04.028

Where:

df = n -3, and
tdf = as listed in Table 1 (see section 17).

Calculate the confidence interval half range at the x value for
[Delta]min as a percentage of the emission limit (CI%) using
Equation 11-28:
[GRAPHIC] [TIFF OMITTED] TR12JA04.029

Where:

CI = the confidence interval half range at the x value that corresponds
to [Delta]min, and
EL = PM emission limit, as described in section 13.2.

(iii) Calculate the tolerance interval half range (TI) at the x
value for [Delta]min, as indicated in Equation 11-29 for the
polynomial correlation, using Equations 11-30 and 11-31:
[GRAPHIC] [TIFF OMITTED] TR12JA04.030

Where:
[GRAPHIC] [TIFF OMITTED] TR12JA04.031

un' = the value indicated in Table 1, and
vdf = the value indicated in Table 1 for df = n-3.

If the calculated value for n is less than 2, then n = 2.
Calculate the tolerance interval half range at the x value for
[Delta]min as a percentage of the emission limit (TI%) using
Equation 11-32:
[GRAPHIC] [TIFF OMITTED] TR12JA04.032

Where:

TI = the tolerance interval half range at the x value that corresponds
to [Delta]min, and
EL = PM emission limit, as described in section 13.2.

(iv) Calculate the polynomial correlation coefficient (r) using
Equation 11-33:
[GRAPHIC] [TIFF OMITTED] TR12JA04.033

Where:

SP = as calculated using Equation 11-26, and
Sy = as calculated using Equation 11-15.

(3) How do I evaluate a logarithmic correlation for my correlation
test data? To evaluate a logarithmic correlation, which has the form
indicated by Equation 11-34, follow the procedures described in
paragraphs (3)(i) through (iii) of this section.
[GRAPHIC] [TIFF OMITTED] TR12JA04.034

(i) Perform a logarithmic transformation of each PM CEMS response
value (x values) using Equation 11-35:
[GRAPHIC] [TIFF OMITTED] TR12JA04.035

Where:

xi' = is the transformed value of xi, and
Ln(xi) = the natural logarithm of the PM CEMS response for
run i.

(ii) Using the values for xi' in place of the values for
xi, perform the same procedures used to develop the linear
correlation equation described in paragraph (1)(i) of this section. The
resulting equation has the form indicated by Equation 11-36:
[GRAPHIC] [TIFF OMITTED] TR12JA04.036

Where:

x' = the natural logarithm of the PM CEMS response, and the variables ,
b0, and b1 are as defined in paragraph (1)(i) of
this section.

(iii) Using the values for xi' in place of the values for
xi, calculate the confidence interval half range at the mean
x' value as a percentage of the emission limit (CI%), the tolerance
interval half range at the mean x' value as a percentage of the emission
limit (TI%), and the correlation coefficient (r) using the procedures
described in paragraphs (1)(ii) through (iv) of this section.
(4) How do I evaluate an exponential correlation for my correlation
test data? To evaluate an exponential correlation, which has the form
indicated by Equation 11-37, follow the procedures described in
paragraphs (4)(i) through (v) of this section:
[GRAPHIC] [TIFF OMITTED] TR12JA04.037

(i) Perform a logarithmic transformation of each PM concentration
measurement (y values) using Equation 11-38:

[[Page 653]]

[GRAPHIC] [TIFF OMITTED] TR12JA04.038

Where:

yi' = is the transformed value of yi, and
Ln(yi) = the natural logarithm of the PM concentration
measurement for run i.

(ii) Using the values for yi in place of the values for
yi' perform the same procedures used to develop the linear
correlation equation described in paragraph (1)(i) of this section. The
resulting equation will have the form indicated by Equation 11-39.
[GRAPHIC] [TIFF OMITTED] TR12JA04.039

Where:

i' = the natural logarithm of the predicted PM concentration
values, and the variables b0, b1, and x are as
defined in paragraph (1)(i) of this section.

(iii) Using the values for yi' in place of the values for
yi, calculate the confidence interval half range (CI), as
described in paragraph (1)(ii) of this section. However, for the
exponential correlation, you must calculate the value for CI at the
median x value, instead of the mean x value for linear correlations.
Calculate the confidence interval half range at the median x value as a
percentage of the emission limit (CI%) using Equation 11-40:
[GRAPHIC] [TIFF OMITTED] TR12JA04.040

Where:

CI = the confidence interval half range at the median x value, and
Ln(EL) = the natural logarithm of the PM emission limit, as described in
section 13.2.

(iv) Using the values for yi' in place of the values for
yi, calculate the tolerance interval half range (TI), as
described in paragraph (1)(iii) of this section. For the exponential
correlation, the value for TI also must be calculated at the median x
value. Calculate the tolerance interval half range at the median x value
as a percentage of the emission limit (TI%) using Equation 11-41:
[GRAPHIC] [TIFF OMITTED] TR12JA04.041

Where:

TI = the tolerance interval half range at the median x value, and
Ln(EL) = the natural logarithm of the PM emission limit, as described in
section 13.2.

(v) Using the values for yi' in place of the values for
yi, calculate the correlation coefficient (r) using the
procedure described in paragraph (1)(iv) of this section.
(5) How do I evaluate a power correlation for my correlation test
data? To evaluate a power correlation, which has the form indicated by
Equation 11-42, follow the procedures described in paragraphs (5)(i)
through (v) of this section.
[GRAPHIC] [TIFF OMITTED] TR12JA04.042

(i) Perform logarithmic transformations of each PM CEMS response (x
values) and each PM concentration measurement (y values) using Equations
11-35 and 11-38, respectively.
(ii) Using the values for xi' in place of the values for
xi, and the values for yi' in place of the values
for yi, perform the same procedures used to develop the
linear correlation equation described in paragraph (1)(i) of this
section. The resulting equation will have the form indicated by Equation
11-43:
[GRAPHIC] [TIFF OMITTED] TR12JA04.043

Where:

' = the natural logarithm of the predicted PM concentration values, and
x' = the natural logarithm of the PM CEMS response values, and the
variables b0 and b1 are as defined in paragraph
(1)(i) of this section.

(iii) Using the values for yi' in place of the values for
yi, calculate the confidence interval half range (CI), as
described in paragraph (1)(ii) of this section. You must calculate the
value for CI at the median x' value, instead of the mean x value for
linear correlations. Calculate the confidence interval half range at the
median x' value as a percentage of the emission limit (CI%) using
Equation 11-40.
(iv) Using the values foryi, in place of the values for
yi, calculate the tolerance interval half range (TI), as
described in paragraph (1)(iii) of this section. The value for TI also
must be calculated at the median x' value. Calculate the tolerance
interval half range at the median x' value as a percentage of the
emission limit (CI%) using Equation 11-41.
(v) Using the values for yi' in place of the values for
yi, calculate the correlation coefficient (r) using the
procedure described in paragraph (1)(iv) of this section.
12.4 Which correlation model should I use? Follow the procedures
described in paragraphs (1) through (4) of this section to determine
which correlation model you should use.
(1) For each correlation model that you develop using the procedures
described in section 12.3 of this specification, compare the confidence
interval half range percentage, tolerance interval half range
percentage, and correlation coefficient to the performance criteria
specified in section 13.2 of this specification. You can use the linear,
logarithmic, exponential, or power correlation model if the model
satisfies all of the performance criteria specified in section 13.2 of
this specification. However, to use the polynomial

[[Page 654]]

model you first must check that the polynomial correlation curve
satisfies the criteria for minimum and maximum values specified in
paragraph (3) of this section.
(2) If you develop more than one correlation curve that satisfy the
performance criteria specified in section 13.2 of this specification,
you should use the correlation curve with the greatest correlation
coefficient. If the polynomial model has the greatest correlation
coefficient, you first must check that the polynomial correlation curve
satisfies the criteria for minimum and maximum values specified in
paragraph (3) of this section.
(3) You can use the polynomial model that you develop using the
procedures described in section 12.3(2) if the model satisfies the
performance criteria specified in section 13.2 of this specification,
and the minimum or maximum value of the polynomial correlation curve
does not occur within the expanded data range. The minimum or maximum
value of the polynomial correlation curve is the point where the slope
of the curve equals zero. To determine if the minimum or maximum value
occurs within the expanded data range, follow the procedure described in
paragraphs (3)(i) through (iv) of this section.
(i) Determine if your polynomial correlation curve has a minimum or
maximum point by comparing the polynomial coefficient b2 to
zero. If b2 is less than zero, the curve has a maximum value.
If b2 is greater than zero, the curve has a minimum value.
(Note: If b2 equals zero, the correlation curve is linear.)
(ii) Calculate the minimum value using Equation 11-44.
[GRAPHIC] [TIFF OMITTED] TR12JA04.044

(iii) If your polynomial correlation curve has a minimum point, you
must compare the minimum value to the minimum PM CEMS response used to
develop the correlation curve. If the correlation curve minimum value is
less than or equal to the minimum PM CEMS response value, you can use
the polynomial correlation curve, provided the correlation curve also
satisfies all of the performance criteria specified in section 13.2 of
this specification. If the correlation curve minimum value is greater
than the minimum PM CEMS response value, you cannot use the polynomial
correlation curve to predict PM concentrations.
(iv) If your polynomial correlation curve has a maximum, the maximum
value must be greater than the allowable extrapolation limit. If your
source is not a low-emitting source, as defined in section 3.16 of this
specification, the allowable extrapolation limit is 125 percent of the
highest PM CEMS response used to develop the correlation curve. If your
source is a low-emitting source, the allowable extrapolation limit is
125 percent of the highest PM CEMS response used to develop the
correlation curve or the PM CEMS response that corresponds to 50 percent
of the emission limit, whichever is greater. If the polynomial
correlation curve maximum value is greater than the extrapolation limit,
and the correlation curve satisfies all of the performance criteria
specified in section 13.2 of this specification, you can use the
polynomial correlation curve to predict PM concentrations. If the
correlation curve maximum value is less than the extrapolation limit,
you cannot use the polynomial correlation curve to predict PM
concentrations.
(4) You may petition the Administrator for alternative solutions or
sampling recommendations if the correlation models described in section
12.3 of this specification do not satisfy the performance criteria
specified in section 13.2 of this specification.

13.0 What Are the Performance Criteria for My PM CEMS?

You must evaluate your PM CEMS based on the 7-day drift check, the
accuracy of the correlation, and the sampling periods and cycle/response
time.
13.1 What is the 7-day drift check performance specification? Your
daily PM CEMS internal drift checks must demonstrate that the average
daily drift of your PM CEMS does not deviate from the value of the
reference light, optical filter, Beta attenuation signal, or other
technology-suitable reference standard by more than 2 percent of the
upscale value. If your CEMS includes diluent and/or auxiliary monitors
(for temperature, pressure, and/or moisture) that are employed as a
necessary part of this performance specification, you must determine the
calibration drift separately for each ancillary monitor in terms of its
respective output (see the appropriate performance specification for the
diluent CEMS specification). None of the calibration drifts may exceed
their individual specification.
13.2 What performance criteria must my PM CEMS correlation satisfy?
Your PM CEMS correlation must meet each of the minimum specifications in
paragraphs (1),

[[Page 655]]

(2), and (3) of this section. Before confidence and tolerance interval
half range percentage calculations are made, you must convert the
emission limit to the appropriate units of your PM CEMS measurement
conditions using the average of emissions gas property values (e.g.,
diluent concentration, temperature, pressure, and moisture) measured
during the correlation test.
(1) The correlation coefficient must satisfy the criterion specified
in paragraph (1)(i) or (ii), whichever applies.
(i) If your source is not a low-emitting source, as defined in
section 3.16 of this specification, the correlation coefficient (r) must
be greater than or equal to 0.85.
(ii) If your source is a low-emitting source, as defined in section
3.16 of this specification, the correlation coefficient (r) must be
greater than or equal to 0.75.
(2) The confidence interval half range must satisfy the applicable
criterion specified in paragraph (2)(i), (ii), or (iii) of this section,
based on the type of correlation model.
(i) For linear or logarithmic correlations, the 95 percent
confidence interval half range at the mean PM CEMS response value from
the correlation test must be within 10 percent of the PM emission limit
value specified in theapplicable regulation, as calculated using
Equation 11-10.
(ii) For polynomial correlations, the 95 percent confidence interval
half range at the PM CEMS response value from the correlation test that
corresponds to the minimum value for [Delta] must be within 10 percent
of the PM emission limit value specified in the applicable regulation,
as calculated using Equation 11-28.
(iii) For exponential or power correlations, the 95 percent
confidence interval half range at the median PM CEMS response value from
the correlation test must be within 10 percent of the natural logarithm
of the PM emission limit value specified in the applicable regulation,
as calculated using Equation 11-40.
(3) The tolerance interval half range must satisfy the applicable
criterion specified in paragraph (3)(i), (ii), or (iii) of this section,
based on the type of correlation model.
(i) For linear or logarithmic correlations, the tolerance interval
half range at the mean PM CEMS response value from the correlation test
must have 95 percent confidence that 75 percent of all possible values
are within 25 percent of the PM emission limit value specified in the
applicable regulation, as calculated using Equation 11-13.
(ii) For polynomial correlations, the tolerance interval half range
at the PM CEMS response value from the correlation test that corresponds
to the minimum value for [Delta] must have 95 percent confidence that 75
percent of all possible values are within 25 percent of the PM emission
limit value specified in the applicable regulation, as calculated using
Equation 11-32.
(iii) For exponential or power correlations, the tolerance interval
half range at the median PM CEMS response value from the correlation
test must have 95 percent confidence that 75 percent of all possible
values are within 25 percent of the natural logarithm of the PM emission
limit value specified in the applicable regulation, as calculated using
Equation 11-41.
13.3 What are the sampling periods and cycle/response time? You must
document and maintain the response time and any changes in the response
time following installation.
(1) If you have a batch sampling PM CEMS, you must evaluate the
limits presented in paragraphs (1)(i) and (ii) of this section.
(i) The response time of your PM CEMS, which is equivalent to the
cycle time, must be no longer than 15 minutes. In addition, the delay
between the end of the sampling time and reporting of the sample
analysis must be no greater than 3 minutes. You must document any
changes in the response time following installation.
(ii) The sampling time of your PM CEMS must be no less than 30
percent of the cycle time. If you have a batch sampling PM CEMS,
sampling must be continuous except during pauses when the collected
pollutant on the capture media is being analyzed and the next capture
medium starts collecting a new sample.
13.4 What PM compliance monitoring must I do? You must report your
CEMS measurements in the units of the standard expressed in the
regulations (e.g., mg/dscm @ 7 percent oxygen, pounds per million Btu
(lb/mmBtu), etc.). You may need to install auxiliary data monitoring
equipment to convert the units reported by your PM CEMS into units of
the PM emission standard.

14.0 Pollution Prevention [Reserved]

15.0 Waste Management [Reserved]

16.0 Which References Are Relevant to This Performance Specification?

16.1 Technical Guidance Document: Compliance Assurance Monitoring.
U.S. Environmental Protection Agency Office of Air Quality Planning and
Standards Emission Measurement Center. August 1998.
16.2 40 CFR 60, Appendix B, ``Performance Specification 2--
Specifications and Test Procedures for SO2, and
NOX, Continuous Emission Monitoring Systems in Stationary
Sources.''
16.3 40 CFR 60, Appendix B, ``Performance Specification 1--
Specification and Test Procedures for Opacity Continuous Emission
Monitoring Systems in Stationary Sources.''

[[Page 656]]

16.4 40 CFR 60, Appendix A, ``Method 1--Sample and Velocity
Traverses for Stationary Sources.''
16.5 ``Current Knowledge of Particulate Matter (PM) Continuous
Emission Monitoring.'' EPA-454/R-00-039. U.S. Environmental Protection
Agency, Research Triangle Park, NC. September 2000.
16.6 40 CFR 266, Appendix IX, Section 2, ``Performance
Specifications for Continuous Emission Monitoring Systems.''
16.7 ISO 10155, ``Stationary Source Emissions--Automated Monitoring
of Mass Concentrations of Particles: Performance Characteristics, Test
Procedures, and Specifications.'' American National Standards Institute,
New York City. 1995.

17.0 What Reference Tables and Validation Data Are Relevant to PS-11?

Use the information in Table 1 for determining the confidence and
tolerance interval half ranges. Use Table 2 to record your 7-day drift
test data.

Table 1.--Factors for Calculation of Confidence and Tolerance Interval Half Ranges
----------------------------------------------------------------------------------------------------------------
df or n' tdf vdf un' (75)
----------------------------------------------------------------------------------------------------------------
2............................................................... 4.303 4.415 1.433
3............................................................... 3.182 2.920 1.340
4............................................................... 2.776 2.372 1.295
5............................................................... 2.571 2.089 1.266
6............................................................... 2.447 1.915 1.247
7............................................................... 2.365 1.797 1.233
8............................................................... 2.306 1.711 1.223
9............................................................... 2.262 1.645 1.214
10.............................................................. 2.228 1.593 1.208
11.............................................................. 2.201 1.551 1.203
12.............................................................. 2.179 1.515 1.199
13.............................................................. 2.160 1.485 1.195
14.............................................................. 2.145 1.460 1.192
15.............................................................. 2.131 1.437 1.189
16.............................................................. 2.120 1.418 1.187
17.............................................................. 2.110 1.400 1.185
18.............................................................. 2.101 1.385 1.183
19.............................................................. 2.093 1.370 1.181
20.............................................................. 2.086 1.358 1.179
21.............................................................. 2.080 1.346 1.178
22.............................................................. 2.074 1.335 1.177
23.............................................................. 2.069 1.326 1.175
24.............................................................. 2.064 1.317 1.174
25.............................................................. 2.060 1.308 1.173
26.............................................................. 2.056 1.301 1.172
27.............................................................. 2.052 1.294 1.172
28.............................................................. 2.048 1.287 1.171
29.............................................................. 2.045 1.281 1.171
30.............................................................. 2.042 1.274 1.170
31.............................................................. 2.040 1.269 1.169
32.............................................................. 2.037 1.264 1.169
33.............................................................. 2.035 1.258 1.168
34.............................................................. 2.032 1.253 1.168
35.............................................................. 2.030 1.248 1.167
36.............................................................. 2.028 1.244 1.167
37.............................................................. 2.026 1.240 1.166
38.............................................................. 2.025 1.236 1.166
39.............................................................. 2.023 1.232 1.165
40.............................................................. 2.021 1.228 1.165
41.............................................................. 2.020 1.225 1.165
42.............................................................. 2.018 1.222 1.164
43.............................................................. 2.017 1.219 1.164
44.............................................................. 2.015 1.216 1.163
45.............................................................. 2.014 1.213 1.163
46.............................................................. 2.013 1.210 1.163
47.............................................................. 2.012 1.207 1.163
48.............................................................. 2.011 1.205 1.162
49.............................................................. 2.010 1.202 1.162
50.............................................................. 2.009 1.199 1.162
51.............................................................. 2.008 1.197 1.162
52.............................................................. 2.007 1.194 1.162
53.............................................................. 2.006 1.191 1.161
54.............................................................. 2.005 1.189 1.161
55.............................................................. 2.005 1.186 1.161
56.............................................................. 2.004 1.183 1.161
57.............................................................. 2.003 1.181 1.161
58.............................................................. 2.002 1.178 1.160

[[Page 657]]

59.............................................................. 2.001 1.176 1.160
60.............................................................. 2.000 1.173 1.160
61.............................................................. 2.000 1.170 1.160
62.............................................................. 1.999 1.168 1.160
63.............................................................. 1.999 1.165 1.159
----------------------------------------------------------------------------------------------------------------

Table 2.--7-Day Drift Test Data
----------------------------------------------------------------------------------------------------------------
Zero drift
Zero drift day Date and time Zero check value PM CEMS response Difference ((RCEMS-RL) /RU)
(RL) (RCEMS) (RCEMS-RL) x 100
----------------------------------------------------------------------------------------------------------------
1
------------------
2
------------------
3
------------------
4
------------------
5
------------------
6
------------------
7
----------------------------------------------------------------------------------------------------------------

[[Page 658]]

PM CEMS Upscale drift
Upscale drift day Date and time Upscale check response Difference ((RCEMS-RU)/RU) x
value (RU) (RCEMS) (RCEMS-RU) 100%
----------------------------------------------------------------------------------------------------------------
1
------------------
2
------------------
3
------------------
4
------------------
5
------------------
6
------------------
7
----------------------------------------------------------------------------------------------------------------

[[Page 659]]

Performance Specification 15--Performance Specification for Extractive
FTIR Continuous Emissions Monitor Systems in Stationary Sources

1.0 Scope and Application

1.1 Analytes. This performance specification is applicable for
measuring all hazardous air pollutants (HAPs) which absorb in the
infrared region and can be quantified using Fourier Transform Infrared
Spectroscopy (FTIR), as long as the performance criteria of this
performance specification are met. This specification is to be used for
evaluating FTIR continuous emission monitoring systems for measuring
HAPs regulated under Title III of the 1990 Clean Air Act Amendments.
This specification also applies to the use of FTIR CEMs for measuring
other volatile organic or inorganic species.
1.2 Applicability. A source which can demonstrate that the
extractive FTIR system meets the criteria of this performance
specification for each regulated pollutant may use the FTIR system to
continuously monitor for the regulated pollutants.

2.0 Summary of Performance Specification

For compound-specific sampling requirements refer to FTIR sampling
methods (e.g., reference 1). For data reduction procedures and
requirements refer to the EPA FTIR Protocol (reference 2), hereafter
referred to as the ``FTIR Protocol.'' This specification describes
sampling and analytical procedures for quality assurance. The infrared
spectrum of any absorbing compound provides a distinct signature. The
infrared spectrum of a mixture contains the superimposed spectra of each
mixture component. Thus, an FTIR CEM provides the capability to
continuously measure multiple components in a sample using a single
analyzer. The number of compounds that can be speciated in a single
spectrum depends, in practice, on the specific compounds present and the
test conditions.

3.0 Definitions

For a list of definitions related to FTIR spectroscopy refer to
Appendix A of the FTIR Protocol. Unless otherwise specified,
spectroscopic terms, symbols and equations in this performance
specification are taken from the FTIR Protocol or from documents cited
in the Protocol. Additional definitions are given below.
3.1 FTIR Continuous Emission Monitoring System (FTIR CEM).
3.1.1 FTIR System. Instrument to measure spectra in the mid-infrared
spectral region (500 to 4000 cm^-1). It contains an infrared
source, interferometer, sample gas containment cell, infrared detector,
and computer. The interferometer consists of a beam splitter that
divides the beam into two paths, one path a fixed distance and the other
a variable distance. The computer is equipped with software to run the
interferometer and store the raw digitized signal from the detector
(interferogram). The software performs the mathematical conversion (the
Fourier transform) of the interferogram into a spectrum showing the
frequency dependent sample absorbance. All spectral data can be stored
on computer media.
3.1.2 Gas Cell. A gas containment cell that can be evacuated. It
contains the sample as the infrared beam passes from the interferometer,
through the sample, and to the detector. The gas cell may have multi-
pass mirrors depending on the required detection limit(s) for the
application.
3.1.3 Sampling System. Equipment used to extract sample from the
test location and transport the gas to the FTIR analyzer. Sampling
system components include probe, heated line, heated non-reactive pump,
gas distribution manifold and valves, flow measurement devices and any
sample conditioning systems.
3.2 Reference CEM. An FTIR CEM, with sampling system, that can be
used for comparison measurements.
3.3 Infrared Band (also Absorbance Band or Band). Collection of
lines arising from rotational transitions superimposed on a vibrational
transition. An infrared absorbance band is analyzed to determine the
analyte concentration.
3.4 Sample Analysis. Interpreting infrared band shapes, frequencies,
and intensities to obtain sample component concentrations. This is
usually performed by a software routine using a classical least squares
(cls), partial least squares (pls), or K- or P- matrix method.
3.5 (Target) Analyte. A compound whose measurement is required,
usually to some established limit of detection and analytical
uncertainty.
3.6 Interferant. A compound in the sample matrix whose infrared
spectrum overlaps at least part of an analyte spectrum complicating the
analyte measurement. The interferant may not prevent the analyte
measurement, but could increase the analytical uncertainty in the
measured concentration. Reference spectra of interferants are used to
distinguish the interferant bands from the analyte bands. An interferant
for one analyte may not be an interferant for other analytes.
3.7 Reference Spectrum. Infrared spectra of an analyte, or
interferant, prepared under controlled, documented, and reproducible
laboratory conditions (see Section 4.6 of the FTIR Protocol). A suitable
library of reference spectra can be used to measure target analytes in
gas samples.
3.8 Calibration Spectrum. Infrared spectrum of a compound suitable
for characterizing the FTIR instrument configuration (Section 4.5 in the
FTIR Protocol).

[[Page 660]]

3.9 One hundred percent line. A double beam transmittance spectrum
obtained by combining two successive background single beam spectra.
Ideally, this line is equal to 100 percent transmittance (or zero
absorbance) at every point in the spectrum. The zero absorbance line is
used to measure the RMS noise of the system.
3.10 Background Deviation. Any deviation (from 100 percent) in the
one hundred percent line (or from zero absorbance). Deviations greater
than 5 percent in any analytical region are
unacceptable. Such deviations indicate a change in the instrument
throughput relative to the single-beam background.
3.11 Batch Sampling. A gas cell is alternately filled and evacuated.
A Spectrum of each filled cell (one discreet sample) is collected and
saved.
3.12 Continuous Sampling. Sample is continuously flowing through a
gas cell. Spectra of the flowing sample are collected at regular
intervals.
3.13 Continuous Operation. In continuous operation an FTIR CEM
system, without user intervention, samples flue gas, records spectra of
samples, saves the spectra to a disk, analyzes the spectra for the
target analytes, and prints concentrations of target analytes to a
computer file. User intervention is permitted for initial set-up of
sampling system, initial calibrations, and periodic maintenance.
3.14 Sampling Time. In batch sampling--the time required to fill the
cell with flue gas. In continuous sampling--the time required to collect
the infrared spectrum of the sample gas.
3.15 PPM-Meters. Sample concentration expressed as the
concentration-path length product, ppm (molar) concentration multiplied
by the path length of the FTIR gas cell. Expressing concentration in
these units provides a way to directly compare measurements made using
systems with different optical configurations. Another useful expression
is (ppm-meters)/K, where K is the absolute temperature of the sample in
the gas cell.
3.16 CEM Measurement Time Constant. The Time Constant (TC, minutes
for one cell volume to flow through the cell) determines the minimum
interval for complete removal of an analyte from the FTIR cell. It
depends on the sampling rate (Rs in Lpm), the FTIR cell
volume (Vcell in L) and the chemical and physical properties
of an analyte.
[GRAPHIC] [TIFF OMITTED] TR17OC00.464

For example, if the sample flow rate (through the FTIR cell) is 5 Lpm
and the cell volume is 7 liters, then TC is equal to 1.4 minutes (0.71
cell volumes per minute). This performance specification defines 5 * TC
as the minimum interval between independent samples.
3.17 Independent Measurement. Two independent measurements are
spectra of two independent samples. Two independent samples are
separated by, at least 5 cell volumes. The interval between independent
measurements depends on the cell volume and the sample flow rate
(through the cell). There is no mixing of gas between two independent
samples. Alternatively, estimate the analyte residence time empirically:
(1) Fill cell to ambient pressure with a (known analyte concentration)
gas standard, (2) measure the spectrum of the gas standard, (3) purge
the cell with zero gas at the sampling rate and collect a spectrum every
minute until the analyte standard is no longer detected
spectroscopically. If the measured time corresponds to less than 5 cell
volumes, use 5 * TC as the minimum interval between independent
measurements. If the measured time is greater than 5 * TC, then use this
time as the minimum interval between independent measurements.
3.18 Test Condition. A period of sampling where all process, and
sampling conditions, and emissions remain constant and during which a
single sampling technique and a single analytical program are used. One
Run may include results for more than one test condition. Constant
emissions means that the composition of the emissions remains
approximately stable so that a single analytical program is suitable for
analyzing all of the sample spectra. A greater than two-fold change in
analyte or interferant concentrations or the appearance of additional
compounds in the emissions, may constitute a new test condition and may
require modification of the analytical program.
3.19 Run. A single Run consists of spectra (one spectrum each) of at
least 10 independent samples over a minimum of one hour. The
concentration results from the spectra can be averaged together to give
a run average for each analyte measured in the test run.

4.0 Interferences

Several compounds, including water, carbon monoxide, and carbon
dioxide, are known interferences in the infrared region in which the
FTIR instrument operates. Follow the procedures in the FTIR protocol for
subtracting or otherwise dealing with these and other interferences.

5.0 Safety

[[Page 661]]

safety and health practices and determine the applicable regulatory
limitations prior to performing these procedures. The CEMS users manual
and materials recommended by this performance specification should be
consulted for specific precautions to be taken.

6.0 Equipment and Supplies

6.1 Installation of sampling equipment should follow requirements of
FTIR test Methods such as references 1 and 3 and the EPA FTIR Protocol
(reference 2). Select test points where the gas stream composition is
representative of the process emissions. If comparing to a reference
method, the probe tips for the FTIR CEM and the RM should be positioned
close together using the same sample port if possible.
6.2 FTIR Specifications. The FTIR CEM must be equipped with
reference spectra bracketing the range of path length-concentrations
(absorbance intensities) to be measured for each analyte. The effective
concentration range of the analyzer can be adjusted by changing the path
length of the gas cell or by diluting the sample. The optical
configuration of the FTIR system must be such that maximum absorbance of
any target analyte is no greater than 1.0 and the minimum absorbance of
any target analyte is at least 10 times the RMSD noise in the analytical
region. For example, if the measured RMSD in an analytical region is
equal to 10^-3, then the peak analyte absorbance is required
to be at least 0.01. Adequate measurement of all of the target analytes
may require changing path lengths during a run, conducting separate runs
for different analytes, diluting the sample, or using more than one gas
cell.
6.3 Data Storage Requirements. The system must have sufficient
capacity to store all data collected in one week of routine sampling.
Data must be stored to a write-protected medium, such as write-once-
read-many (WORM) optical storage medium or to a password protected
remote storage location. A back-up copy of all data can be temporarily
saved to the computer hard drive. The following items must be stored
during testing.
At least one sample interferogram per sampling
Run or one interferogram per hour, whichever is greater. This assumes
that no sampling or analytical conditions have changed during the run.
All sample absorbance spectra (about 12 per hr,
288 per day).
All background spectra and interferograms
(variable, but about 5 per day).
All CTS spectra and interferograms (at least 2
each 24 hour period).
Documentation showing a record of resolution,
path length, apodization, sampling time, sampling conditions, and test
conditions for all sample, CTS, calibration, and background spectra.
Using a resolution of 0.5 cm^-1, with analytical range of
3500 cm^-1, assuming about 65 Kbytes per spectrum and 130 Kb
per interferogram, the storage requirement is about 164 Mb for one week
of continuous sampling. Lower spectral resolution requires less storage
capacity. All of the above data must be stored for at least two weeks.
After two weeks, storage requirements include: (1) all analytical
results (calculated concentrations), (2) at least 1 sample spectrum with
corresponding background and sample interferograms for each test
condition, (3) CTS and calibration spectra with at least one
interferogram for CTS and all interferograms for calibrations, (4) a
record of analytical input used to produce results, and (5) all other
documentation. These data must be stored according to the requirements
of the applicable regulation.

7.0 Reagents and Standards [Reserved]

8.0 Sample Collection, Preservation, Storage, and Transport [Reserved]

9.0 Quality Control

These procedures shall be used for periodic quarterly or semiannual
QA/QC checks on the operation of the FTIR CEM. Some procedures test only
the analytical program and are not intended as a test of the sampling
system.
9.1 Audit Sample. This can serve as a check on both the sampling
system and the analytical program.
9.1.1 Sample Requirements. The audit sample can be a mixture or a
single component. It must contain target analyte(s) at approximately the
expected flue gas concentration(s). If possible, each mixture component
concentration should be NIST traceable ( 2 percent
accuracy). If a cylinder mixture standard(s) cannot be obtained, then,
alternatively, a gas phase standard can be generated from a condensed
phase analyte sample. Audit sample contents and concentrations are not
revealed to the FTIR CEM operator until after successful completion of
procedures in 5.3.2.
9.1.2 Test Procedure. An audit sample is obtained from the
Administrator. Spike the audit sample using the analyte spike procedure
in Section 11. The audit sample is measured directly by the FTIR system
(undiluted) and then spiked into the effluent at a known dilution ratio.
Measure a series of spiked and unspiked samples using the same
procedures as those used to analyze the stack gas. Analyze the results
using Sections 12.1 and 12.2. The measured concentration of each analyte
must be within 5 percent of the expected
concentration (plus the uncertainty), i.e., the calculated correction
factor must be within

[[Page 662]]

0.93 and 1.07 for an audit with an analyte uncertainty of 2 percent.
9.2 Audit Spectra. Audit spectra can be used to test the analytical
program of the FTIR CEM, but provide no test of the sampling system.
9.2.1 Definition and Requirements. Audit spectra are absorbance
spectra that; (1) have been well characterized, and (2) contain
absorbance bands of target analyte(s) and potential interferants at
intensities equivalent to what is expected in the source effluent. Audit
spectra are provided by the administrator without identifying
information. Methods of preparing Audit spectra include; (1)
mathematically adding sample spectra or adding reference and interferant
spectra, (2) obtaining sample spectra of mixtures prepared in the
laboratory, or (3) they may be sample spectra collected previously at a
similar source. In the last case it must be demonstrated that the
analytical results are correct and reproducible. A record associated
with each Audit spectrum documents its method of preparation. The
documentation must be sufficient to enable an independent analyst to
reproduce the Audit spectra.
9.2.2 Test Procedure. Audit spectra concentrations are measured
using the FTIR CEM analytical program. Analytical results must be within
5 percent of the certified audit concentration for
each analyte (plus the uncertainty in the audit concentration). If the
condition is not met, demonstrate how the audit spectra are
unrepresentative of the sample spectra. If the audit spectra are
representative, modify the FTIR CEM analytical program until the test
requirement is met. Use the new analytical program in subsequent FTIR
CEM analyses of effluent samples.
9.3 Submit Spectra For Independent Analysis. This procedure tests
only the analytical program and not the FTIR CEM sampling system. The
analyst can submit FTIR CEM spectra for independent analysis by EPA.
Requirements for submission include; (1) three representative absorbance
spectra (and stored interferograms) for each test period to be reviewed,
(2) corresponding CTS spectra, (3) corresponding background spectra and
interferograms, (4) spectra of associated spiked samples if applicable,
and (5) analytical results for these sample spectra. The analyst will
also submit documentation of process times and conditions, sampling
conditions associated with each spectrum, file names and sampling times,
method of analysis and reference spectra used, optical configuration of
FTIR CEM including cell path length and temperature, spectral resolution
and apodization used for every spectrum. Independent analysis can also
be performed on site in conjunction with the FTIR CEM sampling and
analysis. Sample spectra are stored on the independent analytical system
as they are collected by the FTIR CEM system. The FTIR CEM and the
independent analyses are then performed separately. The two analyses
will agree to within 120 percent for each analyte
using the procedure in Section 12.3. This assumes both analytical
routines have properly accounted for differences in optical path length,
resolution, and temperature between the sample spectra and the reference
spectra.

10.0 Calibration and Standardization

10.1 Calibration Transfer Standards. For CTS requirements see
Section 4.5 of the FTIR Protocol. A well characterized absorbance band
in the CTS gas is used to measure the path length and line resolution of
the instrument. The CTS measurements made at the beginning of every 24
hour period must agree to within 5 percent after
correction for differences in pressure.
Verify that the frequency response of the instrument and CTS
absorbance intensity are correct by comparing to other CTS spectra or by
referring to the literature.
10.2 Analyte Calibration. If EPA library reference spectra are not
available, use calibration standards to prepare reference spectra
according to Section 6 of the FTIR Protocol. A suitable set of analyte
reference data includes spectra of at least 2 independent samples at
each of at least 2 different concentrations. The concentrations bracket
a range that includes the expected analyte absorbance intensities. The
linear fit of the reference analyte band areas must have a fractional
calibration uncertainty (FCU in Appendix F of the FTIR Protocol) of no
greater than 10 percent. For requirements of analyte standards refer to
Section 4.6 of the FTIR Protocol.
10.3 System Calibration. The calibration standard is introduced at a
point on the sampling probe. The sampling system is purged with the
calibration standard to verify that the absorbance measured in this way
is equal to the absorbance in the analyte calibration. Note that the
system calibration gives no indication of the ability of the sampling
system to transport the target analyte(s) under the test conditions.
10.4 Analyte Spike. The target analyte(s) is spiked at the outlet of
the sampling probe, upstream of the particulate filter, and combined
with effluent at a ratio of about 1 part spike to 9 parts effluent. The
measured absorbance of the spike is compared to the expected absorbance
of the spike plus the analyte concentration already in the effluent.
This measures sampling system bias, if any, as distinguished from
analyzer bias. It is important that spiked sample pass through all of
the sampling system components before analysis.
10.5 Signal-to-Noise Ratio (S/N). The measure of S/N in this
performance specification is the root-mean-square (RMS) noise level as
given in Appendix C of the FTIR

[[Page 663]]

Protocol. The RMS noise level of a contiguous segment of a spectrum is
defined as the RMS difference (RMSD) between the n contiguous absorbance
values (Ai) which form the segment and the mean value
(AM) of that segment.
[GRAPHIC] [TIFF OMITTED] TR17OC00.465

A decrease in the S/N may indicate a loss in optical throughput, or
detector or interferometer malfunction.
10.6 Background Deviation. The 100 percent baseline must be between
95 and 105 percent transmittance (absorbance of 0.02 to -0.02) in every
analytical region. When background deviation exceeds this range, a new
background spectrum must be collected using nitrogen or other zero gas.
10.7 Detector Linearity. Measure the background and CTS at three
instrument aperture settings; one at the aperture setting to be used in
the testing, and one each at settings one half and twice the test
aperture setting. Compare the three CTS spectra. CTS band areas should
agree to within the uncertainty of the cylinder standard. If test
aperture is the maximum aperture, collect CTS spectrum at maximum
aperture, then close the aperture to reduce the IR through-put by half.
Collect a second background and CTS at the smaller aperture setting and
compare the spectra as above. Instead of changing the aperture neutral
density filters can be used to attenuate the infrared beam. Set up the
FTIR system as it will be used in the test measurements. Collect a CTS
spectrum. Use a neutral density filter to attenuate the infrared beam
(either immediately after the source or the interferometer) to
approximately \1/2\ its original intensity. Collect a second CTS
spectrum. Use another filter to attenuate the infrared beam to
approximately \1/4\ its original intensity. Collect a third background
and CTS spectrum. Compare the CTS spectra as above. Another check on
linearity is to observe the single beam background in frequency regions
where the optical configuration is known to have a zero response. Verify
that the detector response is ``flat'' and equal to zero in these
regions. If detector response is not linear, decrease aperture, or
attenuate the infrared beam. Repeat the linearity check until system
passes the requirement.

11.0 Analytical Procedure

11.1 Initial Certification. First, perform the evaluation procedures
in Section 6.0 of the FTIR Protocol. The performance of an FTIR CEM can
be certified upon installation using EPA Method 301 type validation (40
CFR, Part 63, Appendix A), or by comparison to a reference Method if one
exists for the target analyte(s). Details of each procedure are given
below. Validation testing is used for initial certification upon
installation of a new system. Subsequent performance checks can be
performed with more limited analyte spiking. Performance of the
analytical program is checked initially, and periodically as required by
EPA, by analyzing audit spectra or audit gases.
11.1.1 Validation. Use EPA Method 301 type sampling (reference 4,
Section 5.3 of Method 301) to validate the FTIR CEM for measuring the
target analytes. The analyte spike procedure is as follows: (1) a known
concentration of analyte is mixed with a known concentration of a non-
reactive tracer gas, (2) the undiluted spike gas is sent directly to the
FTIR cell and a spectrum of this sample is collected, (3) pre-heat the
spiked gas to at least the sample line temperature, (4) introduce spike
gas at the back of the sample probe upstream of the particulate filter,
(5) spiked effluent is carried through all sampling components
downstream of the probe, (6) spike at a ratio of roughly 1 part spike to
9 parts flue gas (or more dilute), (7) the spike-to-flue gas ratio is
estimated by comparing the spike flow to the total sample flow, and (8)
the spike ratio is verified by comparing the tracer concentration in
spiked flue gas to the tracer concentration in undiluted spike gas. The
analyte flue gas concentration is unimportant as long as the spiked
component can be measured and the sample matrix (including
interferences) is similar to its composition under test conditions.
Validation can be performed using a single FTIR CEM analyzing sample
spectra collected sequentially. Since flue gas analyte (unspiked)
concentrations can vary, it is recommended that two separate sampling
lines (and pumps) are used; one line to carry unspiked flue gas and the
other line to carry spiked flue gas. Even with two sampling lines the
variation in unspiked concentration may be fast compared to the interval
between consecutive measurements. Alternatively, two FTIR CEMs can be
operated side-by-side, one measuring spiked sample, the other unspiked
sample. In this arrangement spiked and unspiked measurements can be
synchronized to minimize the affect of temporal variation in the
unspiked analyte concentration. In either sampling arrangement, the
interval between measured concentrations used in the statistical
analysis should be, at least, 5 cell volumes (5 * TC in equation 1). A
validation run consists of, at least, 24 independent analytical results,
12 spiked and 12 unspiked samples. See Section 3.17 for definition of an
``independent'' analytical result. The results are analyzed using
Sections 12.1 and 12.2 to determine if the measurements passed the
validation requirements. Several analytes can be spiked and measured in
the same sampling run, but a separate statistical analysis is

[[Page 664]]

performed for each analyte. In lieu of 24 independent measurements,
averaged results can be used in the statistical analysis. In this
procedure, a series of consecutive spiked measurements are combined over
a sampling period to give a single average result. The related unspiked
measurements are averaged in the same way. The minimum 12 spiked and 12
unspiked result averages are obtained by averaging measurements over
subsequent sampling periods of equal duration. The averaged results are
grouped together and statistically analyzed using Section 12.2.
11.1.1.1 Validation with a Single Analyzer and Sampling Line. If one
sampling line is used, connect the sampling system components and purge
the entire sampling system and cell with at least 10 cell volumes of
sample gas. Begin sampling by collecting spectra of 2 independent
unspiked samples. Introduce the spike gas into the back of the probe,
upstream of the particulate filter. Allow 10 cell volumes of spiked flue
gas to purge the cell and sampling system. Collect spectra of 2
independent spiked samples. Turn off the spike flow and allow 10 cell
volumes of unspiked flue gas to purge the FTIR cell and sampling system.
Repeat this procedure 6 times until the 24 samples are collected. Spiked
and unspiked samples can also be measured in groups of 4 instead of in
pairs. Analyze the results using Sections 12.1 and 12.2. If the
statistical analysis passes the validation criteria, then the validation
is completed. If the results do not pass the validation, the cause may
be that temporal variations in the analyte sample gas concentration are
fast relative to the interval between measurements. The difficulty may
be avoided by: (1) Averaging the measurements over long sampling periods
and using the averaged results in the statistical analysis, (2)
modifying the sampling system to reduce TC by, for example, using a
smaller volume cell or increasing the sample flow rate, (3) using two
sample lines (4) use two analyzers to perform synchronized measurements.
This performance specification permits modifications in the sampling
system to minimize TC if the other requirements of the validation
sampling procedure are met.
11.1.1.2 Validation With a Single Analyzer and Two Sampling Lines.
An alternative sampling procedure uses two separate sample lines, one
carrying spiked flue gas, the other carrying unspiked gas. A valve in
the gas distribution manifold allows the operator to choose either
sample. A short heated line connects the FTIR cell to the 3-way valve in
the manifold. Both sampling lines are continuously purged. Each sample
line has a rotameter and a bypass vent line after the rotameter,
immediately upstream of the valve, so that the spike and unspiked sample
flows can each be continuously monitored. Begin sampling by collecting
spectra of 2 independent unspiked samples. Turn the sampling valve to
close off the unspiked gas flow and allow the spiked flue gas to enter
the FTIR cell. Isolate and evacuate the cell and fill with the spiked
sample to ambient pressure. (While the evacuated cell is filling,
prevent air leaks into the cell by making sure that the spike sample
rotameter always indicates that a portion of the flow is directed out
the by-pass vent.) Open the cell outlet valve to allow spiked sample to
continuously flow through the cell. Measure spectra of 2 independent
spiked samples. Repeat this procedure until at least 24 samples are
collected.
11.1.1.3 Synchronized Measurements With Two Analyzers. Use two FTIR
analyzers, each with its own cell, to perform synchronized spiked and
unspiked measurements. If possible, use a similar optical configuration
for both systems. The optical configurations are compared by measuring
the same CTS gas with both analyzers. Each FTIR system uses its own
sampling system including a separate sampling probe and sampling line. A
common gas distribution manifold can be used if the samples are never
mixed. One sampling system and analyzer measures spiked effluent. The
other sampling system and analyzer measures unspiked flue gas. The two
systems are synchronized so that each measures spectra at approximately
the same times. The sample flow rates are also synchronized so that both
sampling rates are approximately the same (TC1
TC2 in equation 1). Start both systems at the same time.
Collect spectra of at least 12 independent samples with each (spiked and
unspiked) system to obtain the minimum 24 measurements. Analyze the
analytical results using Sections 12.1 and 12.2. Run averages can be
used in the statistical analysis instead of individual measurements.
11.1.1.4 Compare to a Reference Method (RM). Obtain EPA approval
that the method qualifies as an RM for the analyte(s) and the source to
be tested. Follow the published procedures for the RM in preparing and
setting up equipment and sampling system, performing measurements, and
reporting results. Since FTIR CEMS have multicomponent capability, it is
possible to perform more than one RM simultaneously, one for each target
analyte. Conduct at least 9 runs where the FTIR CEM and the RM are
sampling simultaneously. Each Run is at least 30 minutes long and
consists of spectra of at least 5 independent FTIR CEM samples and the
corresponding RM measurements. If more than 9 runs are conducted, the
analyst may eliminate up to 3 runs from the analysis if at least 9 runs
are used.
11.1.1.4.1 RMs Using Integrated Sampling. Perform the RM and FTIR
CEM sampling simultaneously. The FTIR CEM can measure spectra as
frequently as the analyst chooses

[[Page 665]]

(and should obtain measurements as frequently as possible) provided that
the measurements include spectra of at least 5 independent measurements
every 30 minutes. Concentration results from all of the FTIR CEM spectra
within a run may be averaged for use in the statistical comparison even
if all of the measurements are not independent. When averaging the FTIR
CEM concentrations within a run, it is permitted to exclude some
measurements from the average provided the minimum of 5 independent
measurements every 30 minutes are included: The Run average of the FTIR
CEM measurements depends on both the sample flow rate and the
measurement frequency (MF). The run average of the RM using the
integrated sampling method depends primarily on its sampling rate. If
the target analyte concentration fluctuates significantly, the
contribution to the run average of a large fluctuation depends on the
sampling rate and measurement frequency, and on the duration and
magnitude of the fluctuation. It is, therefore, important to carefully
select the sampling rate for both the FTIR CEM and the RM and the
measurement frequency for the FTIR CEM. The minimum of 9 run averages
can be compared according to the relative accuracy test procedure in
Performance Specification 2 for SO2 and NOX CEMs
(40 CFR, Part 60, App. B).
11.1.1.4.2 RMs Using a Grab Sampling Technique. Synchronize the RM
and FTIR CEM measurements as closely as possible. For a grab sampling RM
record the volume collected and the exact sampling period for each
sample. Synchronize the FTIR CEM so that the FTIR measures a spectrum of
a similar cell volume at the same time as the RM grab sample was
collected. Measure at least 5 independent samples with both the FTIR CEM
and the RM for each of the minimum 9 Runs. Compare the Run concentration
averages by using the relative accuracy analysis procedure in 40 CFR,
Part 60, App. B.
11.1.1.4.3 Continuous Emission Monitors (CEMs) as RMs. If the RM is
a CEM, synchronize the sampling flow rates of the RM and the FTIR CEM.
Each run is at least 1-hour long and consists of at least 10 FTIR CEM
measurements and the corresponding 10 RM measurements (or averages). For
the statistical comparison use the relative accuracy analysis procedure
in 40 CFR, Part 60, App. B. If the RM time constant is <\1/2\ the FTIR
CEM time constant, brief fluctuations in analyte concentrations which
are not adequately measured with the slower FTIR CEM time constant can
be excluded from the run average along with the corresponding RM
measurements. However, the FTIR CEM run average must still include at
least 10 measurements over a 1-hr period.

12.0 Calculations and Data Analysis

12.1 Spike Dilution Ratio, Expected Concentration. The Method 301
bias is calculated as follows.
[GRAPHIC] [TIFF OMITTED] TR17OC00.466

Where:

B=Bias at the spike level
Sm=Mean of the observed spiked sample concentrations
Mm=Mean of the observed unspiked sample concentrations
CS=Expected value of the spiked concentration.

The CS is determined by comparing the SF6 tracer
concentration in undiluted spike gas to the SF6 tracer
concentrations in the spiked samples;
[GRAPHIC] [TIFF OMITTED] TR17OC00.467

The expected concentration (CS) is the measured concentration of the
analyte in undiluted spike gas divided by the dilution factor
[GRAPHIC] [TIFF OMITTED] TR17OC00.468

Where:

[anal]dir=The analyte concentration in undiluted spike gas
measured directly by filling the FTIR cell with the spike gas.

If the bias is statistically significant (Section 12.2), Method 301
requires that a correction factor, CF, be multiplied by the analytical
results, and that 0.7 <= CF <= 1.3.
[GRAPHIC] [TIFF OMITTED] TR17OC00.469

12.2 Statistical Analysis of Validation Measurements. Arrange the
independent measurements (or measurement averages) as in Table 1. More
than 12 pairs of measurements can be analyzed. The statistical analysis
follows EPA Method 301, Section 6.3. Section 12.1 of this performance
specification shows the calculations for the bias, expected

[[Page 666]]

spike concentration, and correction factor. This Section shows the
determination of the statistical significance of the bias. Determine the
statistical significance of the bias at the 95 percent confidence level
by calculating the t-value for the set of measurements. First, calculate
the differences, di, for each pair of spiked and each pair of
unspiked measurements. Then calculate the standard deviation of the
spiked pairs of measurements.
[GRAPHIC] [TIFF OMITTED] TR17OC00.470

Where:

di=The differences between pairs of spiked measurements.
SDs=The standard deviation in the di values.
n=The number of spiked pairs, 2n=12 for the minimum of 12 spiked and 12
unspiked measurements.

Calculate the relative standard deviation, RSD, using SDs and
the mean of the spiked concentrations, Sm. The RSD must be
<=50%.
[GRAPHIC] [TIFF OMITTED] TR17OC00.471

Repeat the calculations in equations 7 and 8 to determine SDu
and RSD, respectively, for the unspiked samples. Calculate the standard
deviation of the mean using SDs and SDu from
equation 7.
[GRAPHIC] [TIFF OMITTED] TR17OC00.472

The t-statistic is calculated as follows to test the bias for
statistical significance;
[GRAPHIC] [TIFF OMITTED] TR17OC00.473

where the bias, B, and the correction factor, CF, are given in Section
12.1. For 11 degrees of freedom, and a one-tailed distribution, Method
301 requires that t <=2.201. If the t-statistic indicates the bias is
statistically significant, then analytical measurements must be
multiplied by the correction factor. There is no limitation on the
number of measurements, but there must be at least 12 independent spiked
and 12 independent unspiked measurements. Refer to the t-distribution
(Table 2) at the 95 percent confidence level and appropriate degrees of
freedom for the critical t-value.

16.0 References

1. Method 318, 40 CFR, Part 63, Appendix A (Draft), ``Measurement of
Gaseous Formaldehyde, Phenol and Methanol Emissions by FTIR
Spectroscopy,'' EPA Contract No. 68D20163, Work Assignment 2-18,
February, 1995.
2. ``EPA Protocol for the Use of Extractive Fourier Transform
Infrared (FTIR) Spectrometry in Analyses of Gaseous Emissions from
Stationary Industrial Sources,'' February, 1995.
3. ``Measurement of Gaseous Organic and Inorganic Emissions by
Extractive FTIR

[[Page 667]]

Spectroscopy,'' EPA Contract No. 68-D2-0165, Work Assignment 3-08.
4. ``Method 301--Field Validation of Pollutant Measurement Methods
from Various Waste Media,'' 40 CFR 63, App A.

17.0 Tables, Diagrams, Flowcharts, and Validation Data

Table 1--Arrangement of Validation Measurements for Statistical Analysis
----------------------------------------------------------------------------------------------------------------
Measurement (or average) Time Spiked (ppm) di spiked Unspiked (ppm) di unspiked
----------------------------------------------------------------------------------------------------------------
1........................... .............. S1 ............... U1
-------------------------------------------------------------- -----------------
2........................... .............. S2 S2-S1 U2 U2-U1
-----------------------------
3........................... .............. S3 ............... U3
-------------------------------------------------------------- -----------------
4........................... .............. S4 S4-S3 U4 U4-U3
-----------------------------
5........................... .............. S5 ............... U5
-------------------------------------------------------------- -----------------
6........................... .............. S6 S6-S5 U6 U6-U5
-----------------------------
7........................... .............. S7 ............... U7
-------------------------------------------------------------- -----------------
8........................... .............. S8 S8-S7 U8 U8-U7
-----------------------------
9........................... .............. S9 ............... U9
-------------------------------------------------------------- -----------------
10.......................... .............. S10 S10-S9 U10 U10-U9
-----------------------------
11.......................... .............. S11 ............... U11
-------------------------------------------------------------- -----------------
12.......................... .............. S12 S12-S11 U12 U12-U11
-----------------------------
Average -........ .............. Sm ............... Mm
----------------------------------------------------------------------------------------------------------------

Table 2--t=Values
----------------------------------------------------------------------------------------------------------------
n-1a t-value n-1a t-value n-1a t-value n-1a t-value
----------------------------------------------------------------------------------------------------------------
11 2.201 17 2.110 23 2.069 29 2.045
12 2.179 18 2.101 24 2.064 30 2.042
13 2.160 19 2.093 25 2.060 40 2.021
14 2.145 20 2.086 26 2.056 60 2.000
15 2.131 21 2.080 27 2.052 120 1.980
16 2.120 22 2.074 28 2.048 8 1.960
----------------------------------------------------------------------------------------------------------------
(a)n is the number of independent pairs of measurements (a pair consists of one spiked and its corresponding
unspiked measurement). Either discreet (independent) measurements in a single run, or run averages can be
used.

[48 FR 13327, Mar. 30, 1983 and 48 FR 23611, May 25, 1983, as amended at
48 FR 32986, July 20, 1983; 51 FR 31701, Aug. 5, 1985; 52 FR 17556, May
11, 1987; 52 FR 30675, Aug. 18, 1987; 52 FR 34650, Sept. 14, 1987; 53 FR
7515, Mar. 9, 1988; 53 FR 41335, Oct. 21, 1988; 55 FR 18876, May 7,
1990; 55 FR 40178, Oct. 2, 1990; 55 FR 47474, Nov. 14, 1990; 56 FR 5526,
Feb. 11, 1991; 59 FR 64593, Dec. 15, 1994; 64 FR 53032, Sept. 30, 1999;
65 FR 62130, 62144, Oct. 17, 2000; 65 FR 48920, Aug. 10, 2000; 69 FR
1802, Jan. 12, 2004]

Effective Date Note: At 70 FR 28673, May 18, 2005, appendix B to
part 60 was amended by adding in numerical order new Performance
Specification 12A, effective July 18, 2005. For the convenience of the
user, the added text is set forth as follows:

Appendix B to Part 60--Performance Specifications

* * * * *

Performance Specification 12A--Specifications and Test Procedures For
Total Vapor Phase Mercury Continuous Emission Monitoring Systems in
Stationary Sources

1.0 Scope and Application

1.1 Analyte.

------------------------------------------------------------------------
Analyte CAS No.
------------------------------------------------------------------------
Mercury (Hg)................................................ 7439-97-6
------------------------------------------------------------------------

[[Page 668]]

1.2 Applicability.
1.2.1 This specification is for evaluating the acceptability of
total vapor phase Hg continuous emission monitoring systems (CEMS)
installed on the exit gases from fossil fuel fired boilers at the time
of or soon after installation and whenever specified in the regulations.
The Hg CEMS must be capable of measuring the total concentration in
[mu]g/m\3\ (regardless of speciation) of vapor phase Hg, and recording
that concentration on a wet or dry basis. Particle bound Hg is not
included in the measurements.
This specification is not designed to evaluate an installed CEMS's
performance over an extended period of time nor does it identify
specific calibration techniques and auxiliary procedures to assess the
CEMS's performance. The source owner or operator, however, is
responsible to calibrate, maintain, and operate the CEMS properly. The
Administrator may require, under Clean Air Act (CAA) section 114, the
operator to conduct CEMS performance evaluations at other times besides
the initial test to evaluate the CEMS performance. See Sec. 60.13(c).
1.2.2 For an affected facility that is also subject to the
requirements of subpart I of part 75 of this chapter, the owner or
operator may conduct the performance evaluation of the Hg CEMS according
to Sec. 75.20(c)(1) of this chapter and section 6 of appendix A to part
75 of this chapter, in lieu of following the procedures in this
performance specification.

2.0 Summary of Performance Specification.

Procedures for measuring CEMS relative accuracy, measurement error
and drift are outlined. CEMS installation and measurement location
specifications, and data reduction procedures are included. Conformance
of the CEMS with the Performance Specification is determined.

3.0 Definitions.

3.1 Continuous Emission Monitoring System (CEMS) means the total
equipment required for the determination of a pollutant concentration.
The system consists of the following major subsystems:
3.2 Sample Interface means that portion of the CEMS used for one or
more of the following: sample acquisition, sample transport, sample
conditioning, and protection of the monitor from the effects of the
stack effluent.
3.3 Hg Analyzer means that portion of the Hg CEMS that measures the
total vapor phase Hg mass concentration and generates a proportional
output.
3.4 Data Recorder means that portion of the CEMS that provides a
permanent electronic record of the analyzer output. The data recorder
may provide automatic data reduction and CEMS control capabilities.
3.5 Span Value means the upper limit of the intended Hg
concentration measurement range. The span value is a value equal to two
times the emission standard. Alternatively, for an affected facility
that is also subject to the requirements of subpart I of part 75 of this
chapter, the Hg span value(s) may be determined according to section
2.1.7 of appendix A to part 75 of this chapter.
3.6 Measurement Error (ME) means the absolute value of the
difference between the concentration indicated by the Hg analyzer and
the known concentration generated by a reference gas, expressed as a
percentage of the span value, when the entire CEMS, including the
sampling interface, is challenged. An ME test procedure is performed to
document the accuracy and linearity of the Hg CEMS at several points
over the measurement range.
3.7 Upscale Drift (UD) means the absolute value of the difference
between the CEMS output response and an upscale Hg reference gas,
expressed as a percentage of the span value, when the entire CEMS,
including the sampling interface, is challenged after a stated period of
operation during which no unscheduled maintenance, repair, or adjustment
took place.
3.8 Zero Drift (ZD) means the absolute value of the difference
between the CEMS output response and a zero-level Hg reference gas,
expressed as a percentage of the span value, when the entire CEMS,
including the sampling interface, is challenged after a stated period of
operation during which no unscheduled maintenance, repair, or adjustment
took place.
3.9 Relative Accuracy (RA) means the absolute mean difference
between the pollutant concentration(s) determined by the CEMS and the
value determined by the reference method (RM) plus the 2.5 percent error
confidence coefficient of a series of tests divided by the mean of the
RM tests. Alternatively, for low concentration sources, the RA may be
expressed as the absolute value of the difference between the mean CEMS
and RM values.

4.0 Interferences. [Reserved]

5.0 Safety.

The procedures required under this performance specification may
involve hazardous materials, operations, and equipment. This performance
specification may not address all of the safety problems associated with
these procedures. It is the responsibility of the user to establish
appropriate safety and health practices and determine the applicable
regulatory limitations prior to performing these procedures. The CEMS
user's manual and materials recommended by the RM should be consulted
for specific precautions to be taken.

[[Page 669]]

6.0 Equipment and Supplies.

6.1 CEMS Equipment Specifications.
6.1.1 Data Recorder Scale. The Hg CEMS data recorder output range
must include zero and a high level value. The high level value must be
approximately two times the Hg concentration corresponding to the
emission standard level for the stack gas under the circumstances
existing as the stack gas is sampled. A lower high level value may be
used, provided that the measured values do not exceed 95 percent of the
high level value. Alternatively, for an affected facility that is also
subject to the requirements of subpart I of part 75 of this chapter, the
owner or operator may set the full-scale range(s) of the Hg analyzer
according to section 2.1.7 of appendix A to part 75 of this chapter.
6.1.2 The CEMS design should also provide for the determination of
calibration drift at a zero value (zero to 20 percent of the span value)
and at an upscale value (between 50 and 100 percent of the high-level
value).
6.2 Reference Gas Delivery System. The reference gas delivery system
must be designed so that the flowrate of reference gas introduced to the
CEMS is the same at all three challenge levels specified in Section 7.1
and at all times exceeds the flow requirements of the CEMS.
6.3 Other equipment and supplies, as needed by the applicable
reference method used. See Section 8.6.2.

7.0 Reagents and Standards.

7.1 Reference Gases. Reference gas standards are required for both
elemental and oxidized Hg (Hg and mercuric chloride, HgCl2).
The use of National Institute of Standards and Technology (NIST)-
certified or NIST-traceable standards and reagents is required. The
following gas concentrations are required.
7.1.1 Zero-level. 0 to 20 percent of the span value.
7.1.2 Mid-level. 50 to 60 percent of the span value.
7.1.3 High-level. 80 to 100 percent of the span value.
7.2 Reference gas standards may also be required for the reference
methods. See Section 8.6.2.

8.0 Performance Specification (PS) Test Procedure.

8.1 Installation and Measurement Location Specifications.
8.1.1 CEMS Installation. Install the CEMS at an accessible location
downstream of all pollution control equipment. Since the Hg CEMS sample
system normally extracts gas from a single point in the stack, use a
location that has been shown to be free of stratification for
SO2 and NOX through concentration measurement
traverses for those gases. If the cause of failure to meet the RA test
requirement is determined to be the measurement location and a
satisfactory correction technique cannot be established, the
Administrator may require the CEMS to be relocated.
Measurement locations and points or paths that are most likely to
provide data that will meet the RA requirements are listed below.
8.1.2 Measurement Location. The measurement location should be (1)
at least two equivalent diameters downstream of the nearest control
device, point of pollutant generation or other point at which a change
of pollutant concentration may occur, and (2) at least half an
equivalent diameter upstream from the effluent exhaust. The equivalent
duct diameter is calculated as per 40 CFR part 60, appendix A, Method 1.
8.1.3 Hg CEMS Sample Extraction Point. Use a sample extraction point
(1) no less than 1.0 meter from the stack or duct wall, or (2) within
the centroidal velocity traverse area of the stack or duct cross
section.
8.2 RM Measurement Location and Traverse Points. Refer to PS 2 of
this appendix. The RM and CEMS locations need not be immediately
adjacent.
8.3 ME Test Procedure. The Hg CEMS must be constructed to permit the
introduction of known concentrations of Hg and HgCl2
separately into the sampling system of the CEMS immediately preceding
the sample extraction filtration system such that the entire CEMS can be
challenged. Sequentially inject each of the three reference gases (zero,
mid-level, and high level) for each Hg species. Record the CEMS response
and subtract the reference value from the CEMS value, and express the
absolute value of the difference as a percentage of the span value (see
example data sheet in Figure 12A-1). For each reference gas, the
absolute value of the difference between the CEMS response and the
reference value shall not exceed 5 percent of the span value. If this
specification is not met, identify and correct the problem before
proceeding.
8.4 UD Test Procedure.
8.4.1 UD Test Period. While the affected facility is operating at
more than 50 percent of normal load, or as specified in an applicable
subpart, determine the magnitude of the UD once each day (at 24-hour
intervals, to the extent practicable) for 7 consecutive unit operating
days according to the procedure given in Sections 8.4.2 through 8.4.3.
The 7 consecutive unit operating days need not be 7 consecutive calendar
days. Use either Hg[deg] or HgCl2 standards for this test.
8.4.2 The purpose of the UD measurement is to verify the ability of
the CEMS to conform to the established CEMS response used for
determining emission concentrations or emission rates. Therefore, if
periodic automatic or manual adjustments are made to

[[Page 670]]

the CEMS zero and response settings, conduct the UD test immediately
before these adjustments, or conduct it in such a way that the UD can be
determined.
8.4.3 Conduct the UD test at either the mid-level or high-level
point specified in Section 7.1. Introduce the reference gas to the CEMS.
Record the CEMS response and subtract the reference value from the CEMS
value, and express the absolute value of the difference as a percentage
of the span value (see example data sheet in Figure 12A-1). For the
reference gas, the absolute value of the difference between the CEMS
response and the reference value shall not exceed 5 percent of the span
value. If this specification is not met, identify and correct the
problem before proceeding.
8.5 ZD Test Procedure.
8.5.1 ZD Test Period. While the affected facility is operating at
more than 50 percent of normal load, or as specified in an applicable
subpart, determine the magnitude of the ZD once each day (at 24-hour
intervals, to the extent practicable) for 7 consecutive unit operating
days according to the procedure given in Sections 8.5.2 through 8.5.3.
The 7 consecutive unit operating days need not be 7 consecutive calendar
days. Use either nitrogen, air, Hg[deg] , or HgCl2 standards
for this test.
8.5.2 The purpose of the ZD measurement is to verify the ability of
the CEMS to conform to the established CEMS response used for
determining emission concentrations or emission rates. Therefore, if
periodic automatic or manual adjustments are made to the CEMS zero and
response settings, conduct the ZD test immediately before these
adjustments, or conduct it in such a way that the ZD can be determined.
8.5.3 Conduct the ZD test at the zero level specified in Section
7.1. Introduce the zero gas to the CEMS. Record the CEMS response and
subtract the zero value from the CEMS value and express the absolute
value of the difference as a percentage of the span value (see example
data sheet in Figure 12A-1). For the zero gas, the absolute value of the
difference between the CEMS response and the reference value shall not
exceed 5 percent of the span value. If this specification is not met,
identify and correct the problem before proceeding.
8.6 RA Test Procedure.
8.6.1 RA Test Period. Conduct the RA test according to the procedure
given in Sections 8.6.2 through 8.6.6 while the affected facility is
operating at normal full load, or as specified in an applicable subpart.
The RA test may be conducted during the ZD and UD test period.
8.6.2 RM. Unless otherwise specified in an applicable subpart of the
regulations, use either Method 29 in appendix A to this part, or
American Society of Testing and Materials (ASTM) Method D 6784-02
(incorporated by reference, see Sec. 60.17) as the RM for Hg
concentration. Alternatively, an instrumental RM may be used, subject to
the approval of the Administrator. Do not include the filterable portion
of the sample when making comparisons to the CEMS results. When Method
29 or ASTM D6784-02 is used, conduct the RM test runs with paired or
duplicate sampling systems. When an approved instrumental method is
used, paired sampling systems are not required. If the RM and CEMS
measure on a different moisture basis, data derived with Method 4 in
appendix A to this part shall also be obtained during the RA test.
8.6.3 Sampling Strategy for RM Tests. Conduct the RM tests in such a
way that they will yield results representative of the emissions from
the source and can be compared to the CEMS data. It is preferable to
conduct moisture measurements (if needed) and Hg measurements
simultaneously, although moisture measurements that are taken within an
hour of the Hg measurements may be used to adjust the Hg concentrations
to a consistent moisture basis. In order to correlate the CEMS and RM
data properly, note the beginning and end of each RM test period for
each paired RM run (including the exact time of day) on the CEMS chart
recordings or other permanent record of output.
8.6.4 Number and length of RM Tests. Conduct a minimum of nine RM
test runs. When Method 29 or ASTM D6784-02 is used, only test runs for
which the data from the paired RM trains meet the relative deviation
(RD) criteria of this PS shall be used in the RA calculations. In
addition, for Method 29 and ASTM D 6784-02, use a minimum sample run
time of 2 hours.

Note: More than nine sets of RM tests may be performed. If this
option is chosen, paired RM test results may be excluded so long as the
total number of paired RM test results used to determine the CEMS RA is
greater than or equal to nine. However, all data must be reported,
including the excluded data.

8.6.5 Correlation of RM and CEMS Data. Correlate the CEMS and the RM
test data as to the time and duration by first determining from the CEMS
final output (the one used for reporting) the integrated average
pollutant concentration for each RM test period. Consider system
response time, if important, and confirm that the results are on a
consistent moisture basis with the RM test. Then, compare each
integrated CEMS value against the corresponding RM value. When Method 29
or ASTM D6784-02 is used, compare each CEMS value against the
corresponding average of the paired RM values.
8.6.6 Paired RM Outliers.
8.6.6.1 When Method 29 or ASTM D6784-02 is used, outliers are
identified through the

[[Page 671]]

determination of relative deviation (RD) of the paired RM tests. Data
that do not meet this criteria should be flagged as a data quality
problem. The primary reason for performing paired RM sampling is to
ensure the quality of the RM data. The percent RD of paired data is the
parameter used to quantify data quality. Determine RD for two paired
data points as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY05.021

where Ca and Cb are concentration values
determined from each of the two samples respectively.
8.6.6.2 A minimum performance criteria for RM Hg data is that RD for
any data pair must be <=10 percent as long as the mean Hg concentration
is greater than 1.0 [mu]g/m\3\. If the mean Hg concentration is less
than or equal to 1.0 [mu]g/m\3\, the RD must be <=20 percent. Pairs of
RM data exceeding these RD criteria should be eliminated from the data
set used to develop a Hg CEMS correlation or to assess CEMS RA.
8.6.7 Calculate the mean difference between the RM and CEMS values
in the units of micrograms per cubic meter ([mu]g/m\3\), the standard
deviation, the confidence coefficient, and the RA according to the
procedures in Section 12.0.
8.7 Reporting. At a minimum (check with the appropriate EPA Regional
Office, State or local Agency for additional requirements, if any),
summarize in tabular form the results of the RD tests and the RA tests
or alternative RA procedure, as appropriate. Include all data sheets,
calculations, charts (records of CEMS responses), reference gas
concentration certifications, and any other information necessary to
confirm that the performance of the CEMS meets the performance criteria.

9.0 Quality Control. [Reserved]

10.0 Calibration and Standardization. [Reserved]

11.0 Analytical Procedure.

Sample collection and analysis are concurrent for this PS (see
Section 8.0). Refer to the RM employed for specific analytical
procedures.

12.0 Calculations and Data Analysis.

Summarize the results on a data sheet similar to that shown in
Figure 2-2 for PS 2.
12.1 Consistent Basis. All data from the RM and CEMS must be
compared in units of [mu]g/m\3\, on a consistent and identified moisture
and volumetric basis (STP = 20 [deg]C, 760 millimeters (mm) Hg).
12.1.1 Moisture Correction (as applicable). If the RM and CEMS
measure Hg on a different moisture basis, use Equation 12A-2 to make the
appropriate corrections to the Hg concentrations.
[GRAPHIC] [TIFF OMITTED] TR18MY05.006

In Equation 12-A-2, Bws is the moisture content of the
flue gas from Method 4, expressed as a decimal fraction (e.g., for 8.0
percent H2O, Bws = 0.08).
12.2 Arithmetic Mean. Calculate the arithmetic mean of the
difference, d, of a data set as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY05.007

Where:

n = Number of data points.
12.3 Standard Deviation. Calculate the standard deviation,
Sd, as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY05.008

Where:

[[Page 672]]

[GRAPHIC] [TIFF OMITTED] TR18MY05.009

12.4 Confidence Coefficient (CC). Calculate the 2.5 percent error
confidence coefficient (one-tailed), CC, as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY05.010

12.5 RA. Calculate the RA of a set of data as follows:
[GRAPHIC] [TIFF OMITTED] TR18MY05.011

Where:

[GRAPHIC] [TIFF OMITTED] TR18MY05.032

13.0 Method Performance.

13.1 ME. ME is assessed at zero-level, mid-level and high-level
values as given below using standards for both Hg⁰ and
HgCl2. The mean difference between the indicated CEMS
concentration and the reference concentration value for each standard
shall be no greater than 5 percent of the span value.
13.2 UD. The UD shall not exceed 5 percent of the span value on any
of the 7 days of the UD test.
13.3 ZD. The ZD shall not exceed 5 percent of the span value on any
of the 7 days of the ZD test.
13.4 RA. The RA of the CEMS must be no greater than 20 percent of
the mean value of the RM test data in terms of units of [mu]g/m\3\.
Alternatively, if the mean RM is less than 5.0 [mu]g/m\3\, the results
are acceptable if the absolute value of the difference between the mean
RM and CEMS values does not exceed 1.0 [mu]g/m\3\.

14.0 Pollution Prevention. [Reserved]

15.0 Waste Management. [Reserved]

16.0 Alternative Procedures. [Reserved]

17.0 Bibliography.

17.1 40 CFR part 60, appendix B, ``Performance Specification 2--
Specifications and Test Procedures for SO2 and NOX
Continuous Emission Monitoring Systems in Stationary Sources.''
17.2 40 CFR part 60, appendix A, ``Method 29--Determination of
Metals Emissions from Stationary Sources.''
17.3 ASTM Method D6784-02, ``Standard Test Method for Elemental,
Oxidized, Particle-Bound and Total Mercury in Flue Gas Generated from
Coal-Fired Stationary Sources (Ontario Hydro Method).''

18.0 Tables and Figures.

Table 12A-1.--T-Values
----------------------------------------------------------------------------------------------------------------
na t0.975 na t0.975 na t0.975
----------------------------------------------------------------------------------------------------------------
2........................................................ 12.706 7 2.447 12 2.201
3........................................................ 4.303 8 2.365 13 2.179
4........................................................ 3.182 9 2.306 14 2.160
5........................................................ 2.776 10 2.262 15 2.145
6........................................................ 2.571 11 2.228 16 2.131
----------------------------------------------------------------------------------------------------------------
\a\ The values in this table are already corrected for n-1 degrees of freedom. Use n equal to the number of
individual values.

[[Page 673]]

Figure 12A-1.--ME, ZD and UD Determination
--------------------------------------------------------------------------------------------------------------------------------------------------------
Drift or
Date Time Reference Gas value CEMS measured Absolute difference measurement error
[mu]g/m\3\ value [mu]g/m\3\ (% of span value)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Zero level..........
-----------------------

-----------------------

=======================
Mid level...........
-----------------------

-----------------------

=======================
High level..........
-----------------------

-----------------------

--------------------------------------------------------------------------------------------------------------------------------------------------------

[[Page 674]]

* * * * *