Senior Airman Geoffrey Witter (right) helps his wingman, Airman 1st Class Lenjie Olbrantz, get a drink of water using the M-50 mask drinking tube April 28, 2010, during Operation Saber-Crown at Spangdahlem Air Base, Germany. The exercise was conducted to evaluate the 52nd Fighter Wing's ability to deploy rapidly. (U.S. Air Force photo/Senior Airman Benjamin Wilson)
 

　　Airmen from the 779th Aerospace Medical Squadron, bioenvironmental engineering, prepare to enter a house to search for radioactive materials and hazardous chemicals, during a HAZMAT exercise Feb 1, 2010, at Joint Base Andrews. The excise helped Airmen stay proficient in HAZMAT procedures and decontamination. (U.S. Air Force photo by Airman 1st Class Perry Aston) (Released)

　　2010年2月1日，安德鲁斯联合基地 - 空军779航天医务中队生物环境工程人员在演习中准备进入一房屋搜索放射物质
　　Spangdahlem 空军基地，德国 2010/4/28 - 美空军人员在演习中用 M-50 面罩饮管喝水