Fire suppression guns fire an aqueous film-forming foam in the 3-Bay hangar during a final test of the fire suppression system Sept. 23, 2014, on Grand Forks Air Force Base, North Dakota. The suppression guns spray 110 gallons of foam per square inch onto the floor of the hangar to protect an aircraft in the event of a fire. (U.S. Air Force photo/Senior Airman Xavier Navarro)
Aqueous film-forming foam covers the floor during a fire suppression system test in the 3-Bay hangar Sept. 23, 2014, on Grand Forks Air Force Base, North Dakota. The AFFF foam system test is part of a $3.2 million project to repair the fire suppression system in the hangars to protect aircraft in the event of a fire. (U.S. Air Force photo/Senior Airman Xavier Navarro)