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Title 40

Displaying title 40, up to date as of 7/10/2026. Title 40 was last amended 7/09/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter CAir Programs50 – 99
Part 53Ambient Air Monitoring Reference and Equivalent Methods53.1 – 53.66
Subpart AGeneral Provisions53.1 – 53.16
Subpart BProcedures for Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO253.20 – 53.23
§ 53.20General provisions.
§ 53.21Test conditions.
§ 53.22Generation of test atmospheres.
§ 53.23Test procedures.
Figure B-1 to Subpart B of Part 53
Example
Table B-1 to Subpart B of Part 53
Performance Limit Specifications for Automated Methods
Table B-2 to Subpart B of Part 53
Test Atmospheres
Table B-3 to Subpart B of Part 53
Interferent Test Concentration, 1 Parts per Million
Table B-4 to Subpart B of Part 53
Line Voltage and Room Temperature Test Conditions
Table B-5 to Subpart B of Part 53
Symbols and Abbreviations
Appendix A to Subpart B of Part 53
Optional Forms for Reporting Test Results
Subpart CProcedures for Determining Comparability Between Candidate Methods and Reference Methods53.30 – 53.35
Subpart DProcedures for Testing Performance Characteristics of Methods for PM 1053.40 – 53.43
§ 53.40General provisions.
§ 53.41Test conditions.
§ 53.42Generation of test atmospheres for wind tunnel tests.
§ 53.43Test procedures.
Subpart EProcedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM 2.5 or PM 10-2.553.50 – 53.59
Subpart FProcedures for Testing Performance Characteristics of Class II Equivalent Methods for PM 2.553.60 – 53.66