MACT / GACT Rules

National Emission Standards for Hazardous Air Pollutants (NESHAPs)

Maximum Achievable Control Technology (MACT) and
Generally Available Control Technology (GACT)

The federal Clean Air Act requires the U.S. Environmental Protection Agency (EPA) to regulate emissions of hazardous air pollutants (HAPs) from a published list of industrial source categories. As required under the act, the EPA has developed a list of source categories that must meet control technology requirements for these toxic air pollutants that are known or suspected to cause cancer or other serious health problems, such as reproductive or birth defects, or environmental problems. These standards are called the National Emission Standards for Hazardous Air Pollutants or NESHAPs.

The NESHAPs are found in 40 CFR Part 63 of the Clean Air Act. These standards require application of technology-based emissions standards referred to as Maximum Achievable Control Technology (MACT) or Generally Available Control Technology (GACT). The NESHAPs are delegated to the states, but both the EPA and the states implement and enforce these standards. Compliance with an applicable federal and/or state rule is the responsibility of the facility.

The EPA has finalized almost all of the MACT standards and a majority of the GACT standards to date. North Carolina's implementation information regarding key MACT and GACT regulations can be found in the following links:

• Boiler MACT (Subpart 5D) and CISWI / NHSM
• Boiler GACT (Subpart 6J)
  • List of boiler tune-up professionals
  • Energy Assessments - DAQ Fact Sheet
  • EPA Boiler Videos
• Reciprocating Internal Combustion Engines (Subpart 4Z)

CONTACTS: