Following the incident at Eglin Air Force Base’s Hangar 130, an investigation produced recommendations regarding High Expansion Foam (HEF) suppression systems in three major areas: “changes to HEF suppression system configuration, incident and rescue operations, and HEF system-equipped hangar worker training.”

Because this is of great interest to Harrington Group, Inc. we reviewed the investigator’s findings and have summarized a few of its key points. Meaningful progress often involves extracting key lessons from tragic events; here are the ones we took from the Eglin incident:


  • Knowledge is our most powerful weapon. This would likely take several forms with several different audiences. Employees working in proximity to HEF systems should have formal training about the system, including “…(at a minimum) automatic and manual system activation sequences, alarm sounds and lights, sequence timing, abort switch/button availability and location, specific risks to hangar users with respect to specific areas of the facility (enclosed locations, elevators, stairwells, tool cages, etc.), dangers of HEF (suffocation and contact risks), evacuation, survival methods, and accountability.”
  • In addition, HEF rescue techniques should be incorporated into training for emergency responders. New systems are being installed routinely and preparation is key. Personnel can also be trained on-site with the planned discharge of a working system.

Building modifications and/or preparedness

  • Often, the building itself can be engineered to prevent similar incidents. For example, in this case, the elevator could have been programmed to remain on the third floor in the event of an HEF discharge, movable only with a firefighter key.
  • Alternate emergency exits should be considered for rooms and spaces only accessible from the protected area to ensure there is a way out that does not require passing through the HEF system protected space.
  • As of today, main doors are set to automatically close with the activation of an HEF system. Keeping the building’s system parameters and potential environmental impact in mind, each facility should be reassessed to see if doors should automatically close or be manually operated when a fire or accidental discharge occurs.

HEF system adjustments

  • HEF systems are currently linked with the building’s fire sprinkler system. However, there could be a benefit to converting the HEF system activation sequence into a ‘pre-action’ sequence, requiring something in addition to simply water flow through the sprinkler system. This would potentially mitigate the system’s vulnerability to water pressure fluctuations caused by temperature swings (among other things) and reduce the risk of accidental activation.
  • Every building with an HEF system should have a contingency plan in place for extreme weather conditions. If this last winter taught us anything, it’s to expect the unexpected.
  • The foam suppresses the fire, but what suppresses the foam? Base fire departments with hangars that are HEF-equipped should consider staging a quantity of anti-foam agent with appropriate distribution equipment (e.g., eductors on hoses). This would rapidly break down HEF following a discharge (this measure would be contingent upon extensive research into effectiveness and environmental impact).

What happened at Hangar 130 was at once accidental, devastating, preventable, and ultimately, a learning experience. It’s an example of how we must learn from tragic events in order to prevent them from occurring. It’s our hope that sharing these lessons will help prevent similar incidents in the future.