National Emission Standards for Hazardous Air Pollutants (NESHAP)

National Emission Standards for Hazardous Air Pollutants (NESHAP)

The purpose of EPA’s National Emission Standards for Hazardous Air Pollutants (NESHAP) program is to regulate 187 hazardous air pollutants (HAPs) known to cause cancer or other health issues. HAPs include benzene, mercury, arsenic, and asbestos among many others.

NESHAP regulations are found in both 40 CFR Part 61 and 40 CFR Part 63. The original Part 61 NESHAP standards, promulgated before the 1990 Clean Air Act (CAA) Amendments, regulate seven (7) individual HAPs. The Part 63 NESHAP standards, promulgated after the 1990 CAA Amendments, regulate a much broader range of HAPs in specific source categories.

The Part 63 NESHAPs are also known as Maximum Achievable Control Technology (MACT) standards. The MACT standards were developed based on the HAP emission levels already achieved by the best-performing similar facilities. They generally set a performance level versus prescribe a specific control technology.

Under MACT regulations, facilities are classified as either a “major source” or an “area source”. A facility’s source type depends on its overall potential-to-emit of HAPs as defined below.

Facility (HAP) Source TypeFacility Potential-to-Emit (HAPs)
Major Source PTE ≥ 10 tons/year of a single HAP ≤ 25 tons/year of any combination of HAPs
Area Source Not a HAP “Major Source”

The following are a sampling of EPA’s MACT standards and the source categories they regulate:

MACT Subpart [40 CFR 63 Section]Source CategoryApplies To
Subpart CC (Refinery MACT I) [§63.640 to 657]Petroleum RefineriesMajor Sources
Subpart UUU (Refinery MACT II) [§63.1560 to 1579]
Petroleum RefineriesMajor Sources
Subpart DDDDD (Boiler MACT) [§63.7480 to 7575]
Process Heaters and BoilersMajor Sources
Subpart JJJJJJ (Boiler MACT) [§11193 to 11237]
BoilersArea Sources
Subpart ZZZZ (RICE MACT) [§63.6580 to 6675]
Reciprocating Internal Combustion Engines (RICE)Major Sources and Area Sources
Subpart R [§63.420 to 429]
Bulk Gasoline Distribution Major Sources
Subpart BBBBBB [§63.11080 to 11100]
Bulk Gasoline Distribution Area Sources
Subpart EEEE (OLD MACT) [§63.2330 to 2406]
Organic Liquids DistributionMajor Sources

Davenport Engineering is well versed in the NESHAP standards relevant to your business. Please contact us for assistance or inquiries you have pertaining to specific NESHAP standards.