U.S. Air Force Staff Sgt. Rodney Dowell, 36th Security Forces Squadron wing inspection team member, holds boom sticks during an emergency management exercise May 11, 2017 at Andersen Air Force Base, Guam. Boom sticks are used to produce loud percussive sounds, similar to that of gunfire, to enhance the realism of simulated active-shooter scenarios. (U.S. Air Force photo by Airman 1st Class Jacob Skovo)