Airmen prepare to use an auto-injector on a simulated nerve agent casualty during a readiness exercise on McEntire Joint National Guard Base, S.C., May 4, 2013. Airmen prepare to use an auto-injector on a simulated nerve agent casualty during a readiness exercise on McEntire Joint National Guard Base, S.C., May 4, 2013. SHARE: Download: Full Size (1.52 MB) Tags: Photo Essays Credit: VIRIN: 938217-Q-GAG86-894.jpg Photo Gallery