NATA Submits Proposed Changes to NFPA 409: Standard on Aircraft Hangars

The National Air Transportation Association (NATA) announces it has submitted proposed changes to the National Fire Protection Association (NFPA) 409: Standard on Aircraft Hangars, addressing the issue of foam fire-suppression systems in aircraft hangars. NATA’s comments were developed through a collaboration with its members and the aviation industry. The Association’s comments were also based on the University of Maryland’s research report, "Review of Foam Fire Suppression System Discharges in Aircraft Hangars," written by Dr. James Milke and undergraduate students from the Department of Fire Protection Engineering, of which Dr. Milke serves as Chair.

“The recent report from the University of Maryland confirms what our industry has known for years, that foam fire-suppression systems are not necessary for most hangars, incredibly burdensome, and end up being a costly solution in search of a problem. The data shows that the risk of a fuel fire in a business aviation hangar is virtually nonexistent, while the risk of a foam system inadvertently discharging and damaging aircraft and the environment is incredibly high — amounting to 137 false discharges since 2004,” states NATA COO, Tim Obitts. 

“We are excited to propose these sensible changes to NFPA 409 that help align the standard with the reality of our industry,” says Megan Eisenstein, NATA’s director of Regulatory Affairs.

NATA’s proposed changes address three key elements that will assist in reducing the risk of aircraft and environmental damage from hangar foam fire-suppression systems:

  • Create a new category of hangar called “Hazardous Operations.” This classification will apply to hangars that permit higher risk operations such as doping, hot work, in-hangar fuel transfers, and spray finishing. Typical FBO hangars that are not classified as “Hazardous Operations” would not require foam.
  • Increase the maximum door height requirement for Group II hangars from 28 feet to 35 feet.
  • Reinstate the “Cluster Hangar” exemption that was mistakenly removed during the previous 2016 NFPA 409 revision cycle.

NATA is continuing to ask the industry to register its support of these comments through the website To date, the online support petition has been signed by 337 individuals representing 189 aviation businesses.

The NFPA 409 Technical Committee on Airport Facilities will meet in early 2020 to begin reviewing the public’s comments. The next revision of NFPA 409 will be published in 2021.