Senior Airman Steven McCarthy, 22nd Logistics Readiness Squadron Petroleum, Oils and Lubricants flight fuels laboratory technician, places a membrane filter onto a scale, July 14, 2015, at McConnell Air Force Base, Kan. Each filter is weighed before use in tests to determine the amount of contaminants caught. (U.S. Air Force photo by Senior Airman Victor J. Caputo)