Code of Federal Regulations (Last Updated: October 10, 2024) |
Title 40 - Protection of Environment |
Chapter I - Environmental Protection Agency |
SubChapter C - Air Programs |
Part 50 - National Primary and Secondary Ambient Air Quality Standards |
§ 50.1 - Definitions. |
§ 50.2 - Scope. |
§ 50.3 - Reference conditions. |
§ 50.4 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide). |
§ 50.5 - National secondary ambient air quality standard for sulfur oxides (sulfur dioxide). |
§ 50.6 - National primary and secondary ambient air quality standards for PM10. |
§ 50.7 - National primary and secondary ambient air quality standards for PM2.5. |
§ 50.8 - National primary ambient air quality standards for carbon monoxide. |
§ 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone. |
§ 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone. |
§ 50.11 - National primary and secondary ambient air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator). |
§ 50.12 - National primary and secondary ambient air quality standards for lead. |
§ 50.13 - National primary and secondary ambient air quality standards for PM2.5. |
§ 50.14 - Treatment of air quality monitoring data influenced by exceptional events. |
§ 50.15 - National primary and secondary ambient air quality standards for ozone. |
§ 50.16 - National primary and secondary ambient air quality standards for lead. |
§ 50.17 - National primary ambient air quality standards for sulfur oxides (sulfur dioxide). |
§ 50.18 - National primary ambient air quality standards for PM2.5. |
§ 50.19 - National primary and secondary ambient air quality standards for ozone. |
§ 50.20 - National primary ambient air quality standards for PM2.5. |
Appendix A-1 to Part 50 - Reference Measurement Principle and Calibration Procedure for the Measurement of Sulfur Dioxide in the Atmosphere (Ultraviolet Fluorescence Method) |
Appendix A-2 to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method) |
Appendix A to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method) |
Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High-Volume Method) |
Appendix C to Part 50 - Measurement Principle and Calibration Procedure for the Measurement of Carbon Monoxide in the Atmosphere (Non-Dispersive Infrared Photometry) |
Appendix D to Part 50 - —Reference Measurement Principle and Calibration Procedure for the Measurement of Ozone in the Atmosphere (Chemiluminescence Method) |
Appendix E to Part 50 |
Appendix E to Part 50 - [Reserved] |
Appendix F to Part 50 - Measurement Principle and Calibration Procedure for the Measurement of Nitrogen Dioxide in the Atmosphere (Gas Phase Chemiluminescence) |
Appendix G to Part 50 - Reference Method for the Determination of Lead in Total Suspended Particulate Matter |
Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone |
Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone |
Appendix J to Part 50 - Reference Method for the Determination of Particulate Matter as PM10 in the Atmosphere |
Appendix K to Part 50 - —Interpretation of the National Ambient Air Quality Standards for Particulate Matter |
Appendix L to Part 50 - —Reference Method for the Determination of Fine Particulate Matter as PM2.5 in the Atmosphere |
Appendix M to Part 50 |
Appendix M to Part 50 - [Reserved] |
Appendix N to Part 50 - —Interpretation of the National Ambient Air Quality Standards for PM2.5 |
Appendix O to Part 50 - Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere |
Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone |
Appendix Q to Part 50 - Reference Method for the Determination of Lead in Particulate Matter as PM10 Collected From Ambient Air |
Appendix R to Part 50 - Interpretation of the National Ambient Air Quality Standards for Lead |
Appendix S to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide) |
Appendix T to Part 50 - Interpretation of the Primary National Ambient Air Quality Standards for Oxides of Sulfur (Sulfur Dioxide) |
Appendix U to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone |