The high expansion foam (HEF) system incident in Hangar 130 at Eglin Air Force Base that occurred early in 2014 left a tragic impression on everyone involved. There were questions to answer: What caused the system to trigger? Could it have been prevented? And, what can we learn from this, in terms of processes that can improve the safety of HEF systems?

A previous analysis of the HEF system at Eglin was primarily focused on the function of the system itself and its environmental impact following a discharge in 2012. Fortunately, no injuries resulted from the 2012 incident. The major questions of the investigation involved preventing foam runoff from entering the storm drains that discharged into local streams, however, the human tragedy of the January 8th, 2014 incident gave investigators a different set of issues to tackle.

The Hangar 130 incident provided unprecedented insight into the safety of foam fire protection systems. Up until the time of the incident, recommendations had been largely theoretical. We understood the technical aspects of the system, but we hadn’t seen just how dangerous it could be for building occupants. Loss of life is always tragic and regrettable, but the incident did leave some valuable lessons in its wake.

A major goal, of course, is to ensure that building occupants have adequate warning so that they can exit or avoid the protected area prior to the discharge of foam. The Hangar 130 case illustrates that anyone working in proximity to an HEF system should have a working knowledge of its risks and how to mitigate them. Major lessons learned from the Eglin incident include:

  • Visibility – Foam has historically had relatively benign reputation outside of the fire protection circles. However, this specific type of foam is very different than the kind encountered in bathtubs or at parties; it is a highly dense, visually impenetrable blanket that smothers the senses and is very disorienting. The contractors immersed in the HEF in Hangar 130 that survived navigated their way out by moving along the ground, finding a wall and feeling their way to an exit. The sense of touch is perhaps the only one that can be consistently used in a situation like this.
  • Sound – When emergency personnel were dispatched to find the missing contractors, they quickly discovered that their voices were stopped short by the foam. Verbal communication was virtually impossible.
  • Breathing – Predictably, high expansion foam can and will expand into places like the nose and mouth. As a result, simply remaining conscious is a battle for those who find themselves immersed in HEF. According to the investigation report, effective measures include staying close to a solid surface, clearing a breathing space, and pulling the shirt over the mouth.

Emergency personnel remarked that even for trained professionals, immersion in HEF is a stark, disorienting, and terrifying experience. While these situations are largely preventable, it is vital for all individuals working in proximity to an HEF system to have a basic understanding of risk and survival techniques.