[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: 40CFR1065.135]

[Page 659]
 
                   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. 1065.135  NOX analyzers.

    This section describes the requirements for chemiluminescent 
detectors (CLD) used to measure NOX. Good engineering 
practice may require the use of other detectors.
    (a) A CLD must meet the following requirements:
    (1) Make sure your CLD meets the accuracy and precision 
specifications in ISO 8178-1 (incorporated by reference in Sec. 
1065.1010).
    (2) The NO to NO2 converter must have an efficiency of at 
least 90 percent.
    (3) Use an overflow sampling system for continuous CLDs. (In an 
overflow system excess zero gas or span gas spills out of the probe when 
you are doing zero or span checks.)
    (4) You do not need a heated CLD to test spark-ignition engines.
    (b) Using CLDs is generally acceptable even though they measure only 
NO and NO2, since conventional engines do not emit 
significant amounts of other NOX species.