Master Sgt. Melissa Worley, 1st Special Operations Support Squadron independent duty medical technician, mixes phenol dye with pool water to test for pH and chlorine levels at the Aquatic Center on Hurlburt Field, Fla., July 22, 2015. Worley and other IDMTs train with bioenvironmental to ensure proficiency when testing water conditions. (U.S. Air Force photo/Senior Airman Meagan Schutter)