Marines

Photo Information

Cpl. Paul Krehbiel (right), the chemical, biological, radioactive and nuclear chief with 3rd Radio Battalion, helps a Marine clear CS gas from his gas mask during annual gas chamber training at Boondocker Training Area, March 25, 2014. (U.S. Marine Corps photo by Lance Cpl. Matthew Bragg)

Photo by Lance Cpl. Matthew Bragg

Getting gassed

28 Mar 2014 | Lance Cpl. Matthew Bragg Marine Corps Base Hawaii

“On my mark, you’re going to close your eyes, take a deep breath, and when I give the ‘go-ahead’ you’re going to break the seal with your fingers, touch the glass of your mask and keep them there until I yell, ‘Gas! Gas! Gas!’” explained Cpl. Paul Krehbiel, the chemical, biological, radioactive and nuclear chief with 3rd Radio Battalion. “Close your eyes and take a deep breath. Ready? Break the seal!”

Krehbiel supervised 57 Marines from 3rd Radio Bn. as they completed their annual gas chamber training at Boondocker Training Area, March 25, 2014.

As the CBRN chief for the battalion, Krehbiel is the sole individual responsible for overseeing all 557 Marines’ gas chamber and mission oriented protective-posture training.

“We do gas chamber training annually so Marines are familiar with the gear,” Krehbiel said. “We want them to know the gear is safe and it really works, so we do the best we can to maintain their familiarity with the gas mask and MOPP gear.”

At the gas chamber, Krehbiel tasked one of his fellow Marines to activate the CS gas and spread it around the room. Meanwhile, he stood outside and examined up to 25 Marines individually to ensure each one was properly wearing their equipment before sending them into the chamber.

“At high levels, CS gas could potentially be harmful,” he explained. “However, the doses of CS gas we use aren’t life threatening. The worst thing someone would experience would be coughing, spitting and/or dripping snot. They’ll live.”

Also known as tear gas, CS gas is made from the compound 2-chlorobenzalmalononitrile, and is mainly used as a crowd-control agent.

Most people mistakenly assume CS gas is an actual gas. However, it is actually a solid, dust-like substance that floats in the air at room temperature.

“The contents of the CS gas are packed into tiny capsules, and they’re released when you pour those contents into a container over a heat source,” said Lance Cpl. Alexandra Gehly, a signals intelligence specialist assigned to the S-3 training section with 3rd Radio Bn. “The CS gas reacts to heat, so when the powder touches the hot surface, it quickly expands throughout the chamber.”

Inside the gas chamber, Krehbiel reassured the group that CS gas is harmless to those who have a firm, tight seal on their gas mask. However, a few Marines found themselves struggling to breathe normally inside the chamber. Krehbiel helped each of them clear the excess gas from their masks before continuing with their training.

The Marines performed various exercises to test the integrity of their gas mask, which would ultimately be broken. Before being allowed to exit the gas chamber, the Marines were required to break the seal of their gas mask and touch their fingers to their eyeglass, ensuring the CS gas had ample time to surround their face. Krehbiel walked around the room and made sure each Marine was exposed to the nerve agent before yelling, “Gas! Gas! Gas!”

They rushed to filter the CS gas from the masks. Once everyone established a normal breathing pattern, Krehbiel congratulated everyone on completing their training and led them through the chamber exit.

“The reason Marines conduct exercises in the gas chamber is to raise their heartbeat,” Gehly explained. “You can relate it to being on the battlefield if a nerve agent is present. The elevated heartbeat in the gas chamber would simulate being in action.”

The gas chamber is required to complete annual training for the fiscal year. Marines should contact their unit’s S-3 if they need to undergo this training.


Marine Corps Base Hawaii