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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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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 NNNNNNational Emission Standards for Hazardous Air Pollutants: Hydrochloric Acid Production63.8980 – 63.9075
What This Subpart Covers63.8980 – 63.8995
§ 63.8980What is the purpose of this subpart?
§ 63.8985Am I subject to this subpart?
§ 63.8990What parts of my plant does this subpart cover?
§ 63.8995When do I have to comply with this subpart?
Emission Limitations and Work Practice Standards63.9000
§ 63.9000What emission limitations and work practice standards must I meet?
General Compliance Requirements63.9005
§ 63.9005What are my general requirements for complying with this subpart?
Testing and Initial Compliance Requirements63.9010 – 63.9030
§ 63.9010By what date must I conduct performance tests?
§ 63.9015When must I conduct subsequent performance tests?
§ 63.9020What performance tests and other procedures must I use?
§ 63.9025What are my monitoring installation, operation, and maintenance requirements?
§ 63.9030How do I demonstrate initial compliance with the emission limitations and work practice standards?
Continuous Compliance Requirements63.9035 – 63.9040
§ 63.9035How do I monitor and collect data to demonstrate continuous compliance?
§ 63.9040How do I demonstrate continuous compliance with the emission limitations and work practice standards?
Notifications, Reports, and Records63.9045 – 63.9060
§ 63.9045What notifications must I submit and when?
§ 63.9050What reports must I submit and when?
§ 63.9055What records must I keep?
§ 63.9060In what form and how long must I keep my records?
Other Requirements and Information63.9065 – 63.9075
§ 63.9065What parts of the General Provisions apply to me?
§ 63.9070Who implements and enforces this subpart?
§ 63.9075What definitions apply to this subpart?
Table 1 to Subpart NNNNN of Part 63
Emission Limits and Work Practice Standards
Table 2 to Subpart NNNNN of Part 63
Operating Limits
Table 3 to Subpart NNNNN of Part 63
Performance Test Requirements for HCl Production Affected Sources
Table 4 to Subpart NNNNN of Part 63
Initial Compliance With Emission Limitations and Work Practice Standards
Table 5 to Subpart NNNNN of Part 63
Continuous Compliance With Emission Limitations and Work Practice Standards
Table 6 to Subpart NNNNN of Part 63
Requirements for Reports
Table 7 to Subpart NNNNN of Part 63
Applicability of General Provisions to Subpart NNNNN