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Title 40

Displaying title 40, up to date as of 7/09/2026. 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 57Primary Nonferrous Smelter Orders57.101 – 57.816
Subpart AGeneral57.101 – 57.111
Subpart BThe Application and the NSO Process57.201 – 57.205
§ 57.201Where to apply.
§ 57.202How to apply.
§ 57.203Contents of the application.
§ 57.204EPA action on second period NSOs which have already been issued.
§ 57.205Submission of supplementary information upon relaxation of an SO2 SIP emission limitation.
Subpart CConstant Controls and Related Requirements57.301 – 57.305
§ 57.301General requirements.
§ 57.302Performance level of interim constant controls.
§ 57.303Total plantwide emission limitation.
§ 57.304Bypass, excess emissions and malfunctions.
§ 57.305Compliance monitoring and reporting.
Subpart DSupplementary Control System Requirements57.401 – 57.405
§ 57.401General requirements.
§ 57.402Elements of the supplementary control system.
§ 57.403Written consent.
§ 57.404Measurements, records, and reports.
§ 57.405Formulation, approval, and implementation of requirements.
Subpart EFugitive Emission Evaluation and Control57.501 – 57.505
Subpart FResearch and Development Requirements57.601 – 57.606
Subpart GCompliance Schedule Requirements57.701 – 57.705
Subpart HWaiver of Interim Requirement for Use of Continuous Emission Reduction Technology57.801 – 57.816
Appendix A to Part 57
Primary Nonferrous Smelter Order (NSO) Application