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Title 40

Displaying title 40, up to date as of 7/20/2026. Title 40 was last amended 7/16/2026.
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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 DDDNational Emission Standards for Hazardous Air Pollutants for Mineral Wool Production63.1175 – 63.1199
§ 63.1175What is the purpose of this subpart?
§ 63.1176Where can I find definitions of key words used in this subpart?
§ 63.1177Am I subject to this subpart?
Standards63.1178 – 63.1180
§ 63.1178For cupolas, what standards must I meet?
§ 63.1179For curing ovens or combined collection/curing operations, what standards must I meet?
§ 63.1180When must I meet these standards?
Compliance With Standards63.1181 – 63.1183
§ 63.1181How do I comply with the particulate matter standards for existing, new, and reconstructed cupolas?
§ 63.1182How do I comply with the carbon monoxide, carbonyl sulfide, hydrogen fluoride, and hydrogen chloride standards for existing, new, and reconstructed cupolas?
§ 63.1183How do I comply with the formaldehyde, phenol, and methanol standards for existing, new, and reconstructed combined collection/curing operations?
Additional Monitoring Information63.1184 – 63.1187
§ 63.1184What do I need to know about the design specifications, installation, and operation of a bag leak detection system?
§ 63.1185How do I establish the average operating temperature of an incinerator?
§ 63.1186How may I change the compliance levels of monitored parameters?
§ 63.1187What do I need to know about operations, maintenance, and monitoring plans?
Performance Tests and Methods63.1188 – 63.1190
§ 63.1188What performance test requirements must I meet?
§ 63.1189What test methods do I use?
§ 63.1190How do I determine compliance?
Notification, Recordkeeping, and Reporting63.1191 – 63.1193
§ 63.1191What notifications must I submit?
§ 63.1192What recordkeeping requirements must I meet?
§ 63.1193What reports must I submit?
Other Requirements and Information63.1194 – 63.1199
§ 63.1194Which general provisions apply?
§ 63.1195Who implements and enforces this subpart?
§ 63.1196What definitions should I be aware of?
§ 63.1197Startups and shutdowns.
§§ 63.1198-63.1199 [Reserved]
Table 1 to Subpart DDD of Part 63
Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart DDD of Part 63
Table 2 to Subpart DDD of Part 63
Emissions Limits and Compliance Dates
Appendix A to Subpart DDD of Part 63
Free Formaldehyde Analysis of Insulation Resins by the Hydroxylamine Hydrochloride Method