A B-52H Stratofortress receives a refill of liquid oxygen on Barksdale Air Force Base, La., April 4, 2013. A B-52 can hold up to 75 gallons of liquid oxygen, providing the aircrew with breathable air during high altitude missions. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Staff Sgt. Mitchell Newman and Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, fill lox carts with liquid oxygen on Barksdale Air Force Base, La., April 4, 2013. The liquid oxygen carts are used by crew chiefs to supply a B-52H Stratofortress crew with a source of breathable air during flight. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Staff Sgt. Mitchell Newman, 2nd Logistics Readiness Squadron Fuels Facilities, puts on personal protective equipment prior to refilling liquid oxygen carts on Barksdale Air Force Base, La., April 4, 2013. Personnel handling liquid oxygen must be extremely careful; if skin or other materials come in contact with liquid oxygen it can cause severe frostbite or volatile explosions. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, observes a sample of liquid oxygen for particulates on Barksdale Air Force Base, April 4, 2013. Bohn drew samples of liquid oxygen to test for particulates and odor. If either is found, Bohn must determine what is causing the contamination and restore the oxygen to a useable state. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Staff Sgt. Mitchell Newman and Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, push a filled liquid oxygen cart on Barksdale Air Force Base, La., April 4, 2013. The fuels facilities section is in charge of the reception, storage and distribution on fuel for Barksdale's fleet of B-52H Stratofortress bombers. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Staff Sgt. Mitchell Newman and Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, prepare to fill a lox cart with liquid oxygen on Barksdale Air Force Base, La., April 4, 2013. The fuels facilities section is in charge of the reception, storage and distribution on fuel for Barksdale's fleet of B-52H Stratofortress bombers. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Staff Sgt. Mitchell Newman and Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, fill lox carts with liquid oxygen on Barksdale Air Force Base, La., April 4, 2013. The fuels facilities section is in charge of the receipt, storage and distribution on fuel for Barksdale's fleet of B-52H Stratofortress bombers. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, takes a sample of liquid oxygen as Staff Sgt. Mitchell Newman, 2 LRS Fuels Facilities, observes on Barksdale Air Force Base, La., April 4, 2013. The Airmen drew samples of liquid oxygen to test for particulates and odor. If either is found, the Airmen must determine what is causing the contamination and restore the oxygen to a useable state. (U.S. Air Force photo/Airman 1st Class Andrew Moua)
Staff Sgt. Mitchell Newman and Senior Airman Daniel Bohn, 2nd Logistics Readiness Squadron Fuels Facilities, look over checklists before refilling liquid oxygen carts on Barksdale Air Force Base, La., April 4, 2013. The liquid oxygen carts are used by crew chiefs to supply a B-52H Stratofortress crew with a source of breathable air during flight. (U.S. Air Force photo/Airman 1st Class Andrew Moua)