Clean Air Act Standards


The EPA continually updates the Clean Air Act standards, which includes rules for Area Source boilers and Major Source boilers.

A facility is considered an Area Source, unless it emits 10 tons or more per year of any single air toxic or 25 tons or more per year of any combination of air toxics.  Both Major and Area source requirements vary depending upon: the type of fuel(s) combusted, boiler commissioning date and boiler size. Major source facilities are subject to Boiler MACT requirements.

Get a complete breakdown of Area Source and Major Source EPA rules and resources to ensure compliance:

Publishing the rules in the Federal Register makes them official for the purpose of compliance.

The adjustments to Area Source and Major Source rules reflect new data provided to the EPA, including additional information about real-world performance and conditions under which affected boilers operate. The basic framework for the EPA emissions compliance regulations remains the same. Learn more about: