2nd Lt. Amanda Daley, 79th Medical Wing critical care nurse, tries on a gas mask during her gas mask fit test at Joint Base Andrews, Md., Dec. 6, 2016. Bioenvironmental technicians at JBA are on track to provide approximately 1,000 gas mask fittings to service members from five different installations by the end of the year. (U.S. Air Force photo by Senior Airman Mariah Haddenham)