[Code of Federal Regulations]
[Title 40, Volume 15]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR65.104]

[Page 71-73]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 65_CONSOLIDATED FEDERAL AIR RULE--Table of Contents
 
                        Subpart F_Equipment Leaks
 
Sec.  65.104  Instrument and sensory monitoring for leaks.

    (a) Monitoring for leaks. The owner or operator of a regulated 
source subject to this subpart shall monitor regulated equipment as 
specified in paragraph (a)(1) of this section for instrument monitoring 
and paragraph (a)(2) of this section for sensory monitoring.
    (1) Instrument monitoring for leaks. (i) Valves in gas/vapor service 
and in light liquid service shall be monitored pursuant to Sec.  
65.106(b).
    (ii) Pumps in light liquid service shall be monitored pursuant to 
Sec.  65.107(b).
    (iii) Connectors in gas/vapor service and in light liquid service 
shall be monitored pursuant to Sec.  65.108(b).
    (iv) Agitators in gas/vapor service and in light liquid service 
shall be monitored pursuant to Sec.  65.109(b).

[[Page 72]]

    (v) Pressure relief devices in gas/vapor service shall be monitored 
pursuant to Sec.  65.111(b) and (c).
    (vi) Compressors designated to operate with an instrument reading 
less than 500 parts per million as described in Sec.  65.103(e) shall be 
monitored pursuant to Sec.  65.112(f).
    (2) Sensory monitoring for leaks. (i) Pumps in light liquid service 
shall be observed pursuant to Sec.  65.107(b)(4) and (e)(1)(v).
    (ii) Agitators in gas/vapor service and in light liquid service 
shall be observed pursuant to Sec.  65.109(b)(3) or (e)(1)(v).
    (b) Instrument monitoring methods. Instrument monitoring as required 
under this subpart shall comply with the requirements specified in 
paragraphs (b)(1) through (6) of this section.
    (1) Monitoring method. Monitoring shall comply with Method 21 of 
appendix A of 40 CFR part 60, except as otherwise provided in this 
section.
    (2) Detection instrument performance criteria. (i) Except as 
provided for in paragraph (b)(2)(ii) of this section, the detection 
instrument shall meet the performance criteria of Method 21 of appendix 
A of 40 CFR part 60, except the instrument response factor criteria in 
section 3.1.2(a) of Method 21 shall be for the representative 
composition of the process fluid not each individual organic compound in 
the stream. For process streams that contain nitrogen, air, water, or 
other inerts that are not organic hazardous air pollutants or volatile 
organic compounds, the response factor shall be determined on an inert-
free basis. The response factor may be determined at any concentration 
for which monitoring for leaks will be conducted. Maintain the record 
specified by Sec.  65.119(b)(8).
    (ii) If no instrument is available at the plant site that will meet 
the performance criteria specified in paragraph (b)(2)(i) of this 
section, the instrument readings may be adjusted by multiplying by the 
representative response factor of the process fluid calculated on an 
inert-free basis as described in paragraph (b)(2)(i) of this section.
    (3) Detection instrument calibration procedure. The detection 
instrument shall be calibrated before use on each day of its use by the 
procedures specified in Method 21 of appendix A of 40 CFR part 60.
    (4) Detection instrument calibration gas. Calibration gases shall be 
zero air (less than 10 parts per million of hydrocarbon in air) and the 
gases specified in paragraph (b)(4)(i) of this section except as 
provided in paragraph (b)(4)(ii) of this section.
    (i) Mixtures of methane in air at a concentration no more than 2,000 
parts per million greater than the leak definition concentration of the 
equipment monitored. If the monitoring instrument's design allows for 
multiple calibration scales, then the lower scale shall be calibrated 
with a calibration gas that is no higher than 2,000 parts per million 
above the concentration specified as a leak, and the highest scale shall 
be calibrated with a calibration gas that is approximately equal to 
10,000 parts per million. If only one scale on an instrument will be 
used during monitoring, the owner or operator need not calibrate the 
scales that will not be used during that day's monitoring.
    (ii) A calibration gas other than methane in air may be used if the 
instrument does not respond to methane or if the instrument does not 
meet the performance criteria specified in paragraph (b)(2)(i) of this 
section. In such cases, the calibration gas may be a mixture of one or 
more of the compounds to be measured in air.
    (5) Monitoring performance. Monitoring shall be performed when the 
equipment is in regulated material service or is in use with any other 
detectable material.
    (6) Monitoring data. Monitoring data obtained prior to the regulated 
source becoming subject to the referencing subpart that do not meet the 
criteria specified in paragraphs (b)(1) through (5) of this section may 
still be used to qualify initially for less frequent monitoring under 
the provisions in Sec.  65.106(a)(2), (b)(3), or (b)(4) for valves or 
Sec.  65.108(b)(3) for connectors, provided the departures from the 
criteria or from the specified monitoring frequency of Sec.  
65.106(b)(3) or (4) are minor and do not significantly affect the 
quality of the data. Examples of minor departures are monitoring at a 
slightly different frequency (such as every 6

[[Page 73]]

weeks instead of monthly or quarterly), following the performance 
criteria of section 3.1.2(a) of Method 21 of appendix A of 40 CFR part 
60 instead of paragraph (b)(2) of this section, or monitoring using a 
different leak definition if the data would indicate the presence or 
absence of a leak at the concentration specified in this subpart. 
Failure to use a calibrated instrument is not considered a minor 
departure.
    (c) Instrument monitoring readings and background adjustments. The 
owner or operator may elect to adjust or not to adjust the instrument 
readings for background. If an owner or operator elects not to adjust 
instrument readings for background, the owner or operator shall monitor 
the equipment according to the procedures specified in paragraphs (b)(1) 
through (5) of this section. In such cases, all instrument readings 
shall be compared directly to the applicable leak definition for the 
monitored equipment to determine whether there is a leak or to determine 
compliance with Sec.  65.111(b) (pressure relief devices) or Sec.  
65.112(f) (alternative compressor standard). If an owner or operator 
elects to adjust instrument readings for background, the owner or 
operator shall monitor the equipment according to the following 
procedures:
    (1) The requirements of paragraphs (b)(1) through (5) of this 
section shall apply.
    (2) The background level shall be determined using the procedures in 
Method 21 of appendix A of 40 CFR part 60.
    (3) The instrument probe shall be traversed around all potential 
leak interfaces as close to the interface as possible as described in 
Method 21 of appendix A of 40 CFR part 60.
    (4) The arithmetic difference between the maximum concentration 
indicated by the instrument and the background level shall be compared 
to the applicable leak definition for the monitored equipment to 
determine whether there is a leak or to determine compliance with Sec.  
65.111(b) (pressure relief devices) or Sec.  65.112(f) (alternative 
compressor standard).
    (d) Sensory monitoring methods. Sensory monitoring consists of 
visual, audible, olfactory, or any other detection method used to 
determine a potential leak to the atmosphere.
    (e) Leaking equipment identification and records. (1) When each leak 
is detected, a weatherproof and readily visible identification shall be 
attached to the leaking equipment.
    (2) When each leak is detected, the information specified in 
paragraphs (e)(2)(i) and (ii) of this section shall be recorded and kept 
pursuant to Sec.  65.4(a), except the information for valves complying 
with the 2-year monitoring period allowed under Sec.  65.106(b)(3)(v), 
and connectors complying with the 8-year monitoring period allowed under 
Sec.  65.108(b)(3)(iii) shall be kept 5 years beyond the date of the 
last use of the information to set a monitoring period.
    (i) The instrument, the equipment identification, and the instrument 
operator's name, initials, or identification number if a leak is 
detected or confirmed by instrument monitoring.
    (ii) The date the leak was detected.