You are here: News > Industry News > Aerospace Maximum Achievable Control Technology (MACT) Residual Risk/Technology Review

Aerospace Maximum Achievable Control Technology (MACT) Residual Risk/Technology Review

Contact: David Darling Tuesday, July 09, 2013

The U.S. Environmental Protection Agency (EPA) is currently reviewing the Aerospace Manufacturing Maximum Achievable Control Technology (MACT) standards under the National Emission Standards for Hazardous Air Pollutants rule for aerospace manufacturing. As part of its review, EPA visited 10 facilities and required the aerospace industry to submit detailed information on the coatings used at aerospace manufacturing operations. It appears that the agency is seeking to change the measurement of HAP limits from the current lbs./gal., to volume coating solids.

ACA and industry are engaging on this front in order to ensure that the new limits are technically feasible and cost effective. In addition, based on a recent court ruling, EPA believes that aerospace operations excluded from the original rule (including specialty coatings) must now be regulated.

EPA is required to complete a residual risk and technology review 8 years after a MACT standard is finalized, to see if additional tightening of the MACT standards are needed to eliminate any significant "residual risks" that might remain. EPA is scheduled to release a proposed rule on March 15, 2014 and a final rule on Jan. 1, 2015. It is important to note that EPA must complete residual risk rules for an additional 11 surface coating sectors in the next few years, including Auto and Light Duty Truck, Miscellaneous Metals, and Plastic Parts surface coating rules.

For the Aerospace MACT, ACA has identified the following issues of concern:

  • EPA is considering various standards for primer and topcoat applications – including standards based on solids content (lb. HAP/lb. solids or lb. HAP/gal. solids) or a facility-wide limit (while this may provide flexibility, facilities may not be able to use higher HAP products and meet the limit);  
  • Capture and Control, currently 81%, may be revised based on survey data; and
  • EPA believes that it must set standards for operations that were not regulated in the original MACT standard, including specialty coatings (special purpose coatings, adhesives, and lubricants).

EPA also released an emission rate calculation procedure/assumptions document, and a summary sheet that lists the gallon use and emissions for all the aerospace facilities under review by EPA. ACA has found several problems with the summary sheet. First and foremost, it appears that EPA just added all the HAPs, divided by coatings solids, and developed the lbs HAP/gal solids estimates for each facility, without any understanding as to what the facility actually does. Additionally, ACA believes many of the “synthetic area” facilities should not be on this list, since they applied for synthetic minor status before Sept. 1, 1998 — the first compliance date of the Aerospace MACT. If some of these facilities drop out, then the number could change considerably since EPA details the synthetic minor issue at the bottom of the summary sheet.

ACA’s Industrial Coatings Air Regulatory Committee tracks, reviews, and comments on industrial surface coating regulations, and ACA provides its members with resources to follow and comply with these rules. Further background on the aerospace MACT rulemaking is available at

Contact ACA’s This e-mail address is being protected from spambots. You need JavaScript enabled to view it or This e-mail address is being protected from spambots. You need JavaScript enabled to view it for more information. 


Join ACA Today

ACA offers valued benefits to technical professionals, educators, sales and marketing professionals, and consultants working in the paint and coatings industry. We also offer memberships for students who may be interested in learning more about the industry and retired professionals who have served the industry during their careers.

Membership Information

Did You Know?

The United States exported $1.8 billion in paint and coatings products in 2010, up by 24 percent, or $343 million, from 2009.

Membership Service Center

Phone: (202) 462-6272
Fax: (202) 462-8549
1500 Rhode Island Ave., NW
Washington DC, 20005
Staff: Staff Contacts