NFPA Removes Bizav Hangar Foam Requirement
The National Fire Protection Association’s revision of its 409 Standard on Aircraft Hangars removes the mandate for foam fire systems in Group 2 hangars.
With the 2022 revision to NFPA's Standard on Aircraft Hangars easing the requirements for hangar fire foam systems in Group 2 hangars, costly accidental discharge events such as this could become a less frequent occurrence in the business aviation industry.

The National Fire Protection Association (NFPA) has removed the requirement for foam fire systems in Group 2 hangars under its just-published 409 Standard on Aircraft Hangars—a change long anticipated by the business aviation industry. Group 2 hangars include those with door heights of 28 feet or less and a single hangar bay less than 40,000 sq ft. While NFPA has no rulemaking authority on its own, its guidance is generally accepted as an industry standard and referenced by state and local governments when approving hangar construction.

This measure had been championed by hangar-keepers and NATA, which pointed out the inefficacy of the systems. Despite their propensity for costly accidental discharges, the systems virtually never encountered the types of situations they were originally designed to safeguard against.

"Historically there has only been one path, prescriptive; you are this size hangar, you have to do this," said Michael France, NATA’s managing director of safety and training. “The new standard includes a performance-based design process and a risk-analysis process that provides alternative methods for FBOs and other aviation businesses based upon their specific location, operations hangar designs, and so on, to propose changes to the way they are going to protect against fire, and then empowers the local fire marshal or municipality—whoever has authority—to be able to approve those [changes].”

Under the new standard, FBOs and other aviation businesses with Group 2 hangars would not require the pricey foam systems and could rely on other firefighting equipment such as sprinklers if hazardous activities such as fuel transfer, welding, torch cutting, soldering, fuel tank repairs, and spray finishing are not conducted in them. NATA initially pushed for the establishment of a new category of Group 2 hangars, ones in which such activities were permitted. "Instead of creating a new type of hangar, what [NFPA] did was just create an exemption for an existing type," explained France. "They just said if you are a Group 2 hangar and you prohibit hazardous activities you can now put in a sprinkler system instead of foam."

The revision is good news for those with plans for developing new hangars, as the foam systems can add 30 to 40 percent to the total cost of construction. But even for those with hangars already so equipped, the possible deactivation and removal of these systems could save them thousands of dollars a year in periodic maintenance and testing, along with avoiding the threat of an accidental foam discharge, which can cost millions of dollars in remediation, system resetting, and repairs to any unfortunate aircraft caught within.

France explained that his organization's focus is now on creating educational materials to create awareness of the new standard. "Then from there, we will begin to help our membership understand how to leverage that standard whether it is new hangar development or with existing hangars wanting to migrate away from a foam system." He noted that hangar operators can now use this new 409 standard in their discussions with their local authorities. "If I were an FBO and I had a foam system, I would begin that conversation with 'Have you seen the new standard, there are some changes in it. How do you see that impacting our ability to shut down our foam system and move to a closed head sprinkler system or something along those lines?'" 

Along with the foam system revision, NATA had requested a height change to the hangar doors under the Group II classification, due to the increasing size of large-cabin business jets. While the NFPA technical committee rejected an across-the-board door height increase for the category at its meeting earlier this year, the organization's standards council, its ultimate deciding body, acknowledged that the performance design review and the risk analysis processes were perfectly acceptable routes for a developer to request an increased door height for their new hangar on an ad hoc basis. "Really the door height was the one thing we really hoped to get that we did not," France told AIN, "but we do have a pathway for FBOs to be able to design and submit for approval hangars that have door heights above 28 feet, yet maintain Group 2 protection requirements.

"As we've said all along, the [hangar fire protection] codes needed to begin the process of modernization, and we think this is a great first step," France concluded.