Tech. Sgt. James Warren, 436th Operational Medical Readiness Squadron bioenvironmental engineering flight noncommissioned officer in charge, tests non-potable water for pH and chlorine levels March 18, 2020, at the main gate on Dover Air Force Base, Delaware. Warren used a Hach DR900 Colorimeter to perform the two tests on the water used by 436th Operational Medical Readiness Squadron personnel to wash their hands. After applying hand sanitizer during the screening of medical clinic patrons, 436th OMRS personnel were required to wash their hands after the fifth screening before reapplying more hand sanitizer. (U.S. Air Force photo by Roland Balik)