More than 60 Marines entered the gas chamber, performing exercises and practicing the technique of donning and clearing their masks to prevent being effected by the gas.
(Official U.S. Marine Corps Photo by Lance Cpl. Meloney R. Moses)

More than 60 Marines from the Modern Basic Skills Training group entered the gas chamber for their annual brief and gas mask operation instruction.
(Official U.S. Marine Corps Photo by Lance Cpl. Meloney R. Moses)

Among many others, Lance Cpl. Alexander Courts endures the sting of gas along with a runny nose. This annual training took place during the last MBST.
(Official U.S. Marine Corps Photo by Lance Cpl. Meloney R. Moses)