Staff Sgt. Pawel Olszowski, 8th Maintenance Squadron aircraft fuels systems specialist, sets a caution sign during a simulated F-16 Fighting Falcon hydrazine leak at Kunsan Air Base, Republic of Korea, Nov. 4, 2021. The hydrazine solution used by F-16s consists of 70 percent hydrazine and 30 percent water, classifying it as a hazardous material. (U.S. Air Force photo by Staff Sgt. Mya M. Crosby)