Airman 1st Class Nathanael Markley, 36th Logistics Readiness Squadron cryogenic production technician, transports a sample that was pulled for testing April 8, 2015, at Andersen Air Force Base, Guam. Cryogenics Airmen produce liquid oxygen and nitrogen as well as gaseous oxygen and nitrogen. (U.S. Air Force photo by Senior Airman Katrina M. Brisbin/Released)