Airman 1st Class Peter Cambra, 779th Aerospace Medicine Squadron bioenvironmental engineer technician, places an air sampler on Tech. Sgt. John Mills-Hearne, a painter with the 459th Reserve Air Refueling Wing Jan. 23, 2013 on Joint Base Andrews, Md. Bioenvironmental Engineers are required to sample air on location to help monitor the amount of chemicals workers are exposed to. (U.S Air Force photo/ Airman 1st Class Erin O’Shea)