US Air Force (USAF) Airmen First Class (A1C) Angel Nivar, 436th Transportation Unit, armed with a 5.56mm M16A2 rifle wears his Mission-Oriented Protective Posture response level 4 (MOPP-4) gears as he guards the entrance to the transportation building during a simulated chemical attack, conducted during Exercise CRISIS REACH 02-19B, at the Combat Readiness Training Center (CRTC), located at the Savannah International Airport (IAP), Georgia (GA)