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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 63National Emission Standards for Hazardous Air Pollutants for Source Categories63.1 – 63.12099
Subpart XXNational Emission Standards for Ethylene Manufacturing Process Units: Heat Exchange Systems and Waste Operations63.1080 – 63.1097
Introduction63.1080 – 63.1081
§ 63.1080What is the purpose of this subpart?
§ 63.1081When must I comply with the requirements of this subpart?
Definitions63.1082
§ 63.1082What definitions do I need to know?
Applicability for Heat Exchange Systems63.1083 – 63.1084
§ 63.1083Does this subpart apply to my heat exchange system?
§ 63.1084What heat exchange systems are exempt from the requirements of this subpart?
Heat Exchange System Requirements63.1085
§ 63.1085What are the general requirements for heat exchange systems?
Monitoring Requirements for Heat Exchange Systems63.1086
§ 63.1086How must I monitor for leaks to cooling water?
Repair Requirements for Heat Exchange Systems63.1087 – 63.1088
§ 63.1087What actions must I take if a leak is detected?
§ 63.1088In what situations may I delay leak repair, and what actions must I take for delay of repair?
Recordkeeping and Reporting Requirements for Heat Exchange Systems63.1089 – 63.1090
§ 63.1089What records must I keep?
§ 63.1090What reports must I submit?
Background for Waste Requirements63.1091 – 63.1092
§ 63.1091What do the waste requirements do?
§ 63.1092What are the major differences between the requirements of 40 CFR part 61, subpart FF, and the waste requirements for ethylene production sources?
Applicability for Waste Requirements63.1093 – 63.1094
§ 63.1093Does this subpart apply to my waste streams?
§ 63.1094What waste streams are exempt from the requirements of this subpart?
Waste Requirements63.1095 – 63.1096
§ 63.1095What specific requirements must I comply with?
§ 63.1096What requirements must I comply with if I transfer waste off-site?
Implementation and Enforcement63.1097
§ 63.1097Who implements and enforces this subpart?
Table 1 to Subpart XX of Part 63
Hazardous Air Pollutants
Table 2 to Subpart XX of Part 63
Requirements of 40 CFR Part 61, Subpart FF, Not Included in the Requirements for This Subpart and Alternate Requirements