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Title 40

Displaying title 40, up to date as of 7/16/2026. Title 40 was last amended 7/16/2026.
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  1. Title 40 —Protection of Environment
  2. Chapter I —Environmental Protection Agency
  3. Subchapter C —Air Programs
  4. Part 63 —National Emission Standards for Hazardous Air Pollutants for Source Categories
  5. Subpart TTTTT   View Full Text
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eCFR Content

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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 TTTTTNational Emissions Standards for Hazardous Air Pollutants for Primary Magnesium Refining63.9880 – 63.9942
What This Subpart Covers63.9880 – 63.9883
§ 63.9880What is the purpose of this subpart?
§ 63.9881Am I subject to this subpart?
§ 63.9882What parts of my plant does this subpart cover?
§ 63.9883When do I have to comply with this subpart?
Emission Limitations and Work Practice Standards63.9890 – 63.9891
§ 63.9890What emission limitations must I meet?
§ 63.9891What work practice standards must I meet for my fugitive dust sources?
Operation and Maintenance Requirements63.9900
§ 63.9900What are my operation and maintenance requirements?
General Compliance Requirements63.9910
§ 63.9910What are my general requirements for complying with this subpart?
Initial Compliance Requirements63.9911 – 63.9918
§ 63.9911By what date must I conduct performance tests or other initial compliance demonstrations?
§ 63.9912When must I conduct subsequent performance tests?
§ 63.9913What test methods and other procedures must I use to demonstrate initial compliance with the emission limits for particulate matter and PM10?
§ 63.9914What test methods and other procedures must I use to demonstrate initial compliance with chlorine and hydrochloric acid emission limits?
§ 63.9915What test methods and other procedures must I use to demonstrate initial compliance with dioxin/furan emission limits?
§ 63.9916What test methods and other procedures must I use to establish and demonstrate initial compliance with the operating limits?
§ 63.9917How do I demonstrate initial compliance with the emission limitations and work practice standards that apply to me?
§ 63.9918How do I demonstrate initial compliance with the operation and maintenance requirements that apply to me?
Continuous Compliance Requirements63.9920 – 63.9925
§ 63.9920What are my continuous monitoring requirements?
§ 63.9921What are the installation, operation and maintenance requirements for my monitors?
§ 63.9922How do I monitor and collect data to demonstrate continuous compliance?
§ 63.9923How do I demonstrate continuous compliance with the emission limitations and work practice standards that apply to me?
§ 63.9924How do I demonstrate continuous compliance with the operation and maintenance requirements that apply to me?
§ 63.9925What other requirements must I meet to demonstrate continuous compliance?
Notifications, Reports, and Records63.9930 – 63.9933
§ 63.9930What notifications must I submit and when?
§ 63.9931What reports must I submit and when?
§ 63.9932What records must I keep?
§ 63.9933In what form and how long must I keep my records?
Other Requirements and Information63.9940 – 63.9942
§ 63.9940What parts of the General Provisions apply to me?
§ 63.9941Who implements and enforces this subpart?
§ 63.9942What definitions apply to this subpart?
Table 1 to Subpart TTTTT of Part 63
Emission Limits
Table 2 to Subpart TTTTT of Part 63
Toxic Equivalency Factors
Table 3 to Subpart TTTTT of Part 63
Initial Compliance With Emission Limits
Table 4 to Subpart TTTTT of Part 63
Continuous Compliance With Emission Limits
Table 5 to Subpart TTTTT of Part 63
Applicability of General Provisions to Subpart TTTTT of Part 63
eCFR Content