[Code of Federal Regulations]
[Title 40, Volume 30]
[Revised as of July 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR1065.125]

[Page 658]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 1065_TEST PROCEDURES AND EQUIPMENT--Table of Contents
 
                    Subpart B_Equipment and Analyzers
 
Sec. 1065.125  Analyzers (overview/general response characteristics).

    (a) General. The following sections and subparts describe the 
specifications for analyzers and analytical equipment:
    (1) The analyzers for measuring hydrocarbon, NOX, CO, and 
CO2 emission concentrations are specified in Sec. 1065.130 
through Sec. 1065.140.
    (2) The analytical equipment for measuring particulate emissions is 
specified in Subpart H of this part.
    (3) The analytical equipment for measuring emissions of oxygenated 
compounds (for example, methanol) is specified in Subpart I of this 
part.
    (4) The analytical equipment for measuring in-use emissions is 
specified in Subpart J of this part.
    (b) Response time. Analyzers must have the following response 
characteristics:
    (1) For steady-state testing and transient testing with bag sample 
analysis, the analyzer must reach at least 90 percent of its final 
response within 5.0 seconds after any step change to the input 
concentration at or above 80 percent of full scale.
    (2) For transient testing with continuous measurement, the analyzer 
must reach at least 90 percent of its final response within 1.0 second 
after any step change to the input concentration at or above 80 percent 
of full scale.
    (c) Precision and noise. Analyzers must meet the following 
characteristics for precision and noise:
    (1) Precision must be no worse than 1 percent 
of full-scale concentration for each range used above 155 ppm (or ppmC), 
or 2 percent for each range used below 155 ppm (or 
ppmC). For this paragraph (c)(1), we define precision as 2.5 times the 
standard deviation of 10 repetitive responses to a given calibration or 
span gas.
    (2) Peak-to-peak response to zero and calibration or span gases over 
any 10-second period must be no more than 2 percent of full-scale chart 
deflection on all ranges used.
    (d) Drift. Analyzers must meet specifications for zero-response and 
span drift.
    (1) The zero-response drift during one hour must be less than 2 
percent of full-scale chart deflection on the lowest range used. Zero-
response is the mean response, including noise, to a zero-gas during a 
30-second interval.
    (2) The span drift during one hour must be less than 2 percent of 
full-scale chart deflection on the lowest range used. Span is the 
difference between the span-response and the zero-response. Span-
response is the mean response, including noise, to a span gas during a 
30-second interval.
    (e) Calibration. See subpart D of this part for specifications to 
calibrate analyzers.