The “Water Only” Fire Protection Fallacy for Group 1 Aircraft Hangars

Some smaller fire protection engineering firms still assure clients that water alone can control a jet-fuel spill fire, arguing that the rarity of hangar fires makes the risk acceptable. We consider this stance negligent and a breach of a fire protection engineer’s professional responsibility as it is not based on tested data.

To demonstrate, we conducted an experiment by spilling 120 gallons of jet fuel and attempting to extinguish it using only water. This amount is merely a fraction of the fuel load of modern aircraft.

Here is what happened.

NFPA 409 and FMDS 7-93 both prohibit water-only fire protection for maintenance aircraft hangars because no full-scale fire testing has demonstrated that a water-only approach can reliably extinguish an ignitable liquid pool fire, regardless of the water flow rate provided.

Code-compliant, prescriptive fire protection is essential for protecting aircraft, personnel, and daily hangar operations. Clients deserve systems that meet the standards and perform as intended.

This is why ILDFA exists.