Freezing Air: Airmen prepare liquid oxygen for sampling
[From left] U.S. Air Force Tech. Sgt. Jason Powers, 20th Logistics Readiness Squadron NCO in charge of fuels fixed facilities, and Staff Sgt. Adam Rozell, 20th LRS fuels fixed facilities supervisor, stand in their protective gear beside a liquid oxygen tank during routine sampling at Shaw Air Force Base, S.C., June 26, 2014. The two cryogenic experts take samples from the liquid oxygen tank approximately every 60 days. Once collected, samples are sent to Wright-Patterson AFB, Ohio for purity testing. (U.S. Air Force photo by Airman 1st Class Jensen Stidham/Released)