Recruits and the Gas Chamber

About three weeks into boot camp, during Weapons and Field training, recruits will be trained on how to use a gas mask. As part of this training, recruits will be led to a gas chamber where they will have to take off their masks. It’s not a particularly pleasant thing to experience, but no permanent damage will occur.

It is preceded by classroom training, where recruits are instructed on how to use a gas mask and why it is important.

Q. What kind of gas is used in the Marine boot camp gas chamber?

A. The gas is called chlorobenzylidene malonitrile, CS gas for short. The gas is non-lethal, used by all military branches and police departments. It’s the gas that is commonly used to disperse riots, unruly gatherings, and so on.

Q. How long are recruits in the gas chamber without their masks on?

While it may seem a lot longer, the truth is that recruits are only in the gas chamber for a matter of minutes, usually 3-5.

Q. What happens inside of the gas chamber?

Recruits enter the gas chamber with their gas masks on. The door to the gas chamber will then be closed. It is a somewhat disconcerting feeling, but it is done for good reason and recruits all go in together at the same time. Recruits are then instructed to break the seal on their gas masks. Recruits will inevitably feel and inhale some of the gas and recruits eyes will start to water, some coughing usually happens. They will then be told to re-seal their masks again.

Then, recruits will be instructed to remove their masks more by putting them on top of their heads. This time recruits will start to feel the gas more as it reaches their lungs. Their eyes get very watery, coughing gets more intense and the gas can be felt on the skin…a mild burning sensation similar to a sunburn. Some recruits tend to start to panic at this stage as they feel that they are losing control. That is actually one of the points of this exercise, to help train recruits to regain control and rely on their training.

The recruits are directed to put their masks back on, regaining control again. Then, for a third time, recruits are instructed to remove their masks, this time entirely. They are told to hold their masks out in front of them. They are then told to leave the gas chamber with their arms spread out. Recruits typically come out with watery eyes, coughing…some recruits even throw up.

Q. What’s the purpose of the gas chamber in boot camp?

The goal is to get recruits to understand and have confidence in their gas masks. It’s to train them that the mask will protect them so that they will not have doubts about it when it’s actually being used in battle or on a mission. It teaches them that if they do inhale tear gas, they will not die from it. It teaches them to regain control if they start to panic.

13 thoughts on “Recruits and the Gas Chamber”

  1. No, you don’t ‘get used to it.’ Rather, you are learning how not to ‘panic.’ How to deal and react to it. In a calm, clearing thinking, deliberate manner. You learn not to let the possible chaos going on around you, to get the better of you. Semper Fi, to God and country.

  2. Hello..i actually have questions. How many times would i have to do the gas mask during boot camp? Also by putting the gas mask on do it prevent the gas from taking your breath after the seal has been broken?

  3. My training and “Introduction to CS” went a little different (3026, Kilo Co, 3rd Bn/2nd Marines. Took boot on PI, but stationed on Camp Hansen, Okinawa). Upon entrance to “The Chamber”, the canister was popped and after about two minutes, we were instructed to remove our gas mask ( The MCU-2/P Protective mask @ that time).
    We were instructed to “calmly state your name, rank, and serial number, in an orderly and profound military manner, PRIOR (EXCLAIMED) to exiting this (the DI swept his arms open) my BEAUTIFUL INVITATIONAL RECEPTION AREA! LADIES, DO YOU UNDERSTAND”? To which our reply was “SIR, YES SIR”! (LMAO)!! They then came front and center to you, individually, and you had to remove your mask and do as instructed. WE ALL WERE THROWING UP, COUGHING, AND HAD SNOTTY NOSES, TRYING TO DO THIS SHIT! LMMFAO!!
    The DIs had a BALL watching us ATTEMPT to do this! Ohhh the MEMORIES! At 17, I THOUGHT I was INDESTRUCTIBLE! I learned otherwise. THANK YOU USMC for the MUCH NEEDED “lesson” in life. I wouldn’t have it any other way. SEMPER FI!

  4. In 1966 we went into the chamber with the mask’ on. The tear gas was released, we were instructed to remove the mask and sing the Marine Corp Hymn. After several verses we were ordered to march out of the chamber. Tough training.

  5. When I went through the gas chamber it was in 1969. I went through ITR at San Onafra Camp Pendleton. Things seem to have changed quite a bit since then. We also only had an 8 week boot camp and 4 weeks at ITR

    1. Do you now have bulios emphysema or lung issues. Be clause the gas chamber I was in was crystal clear and shiny flakes floating in the chamber

  6. The gas chamber is one of the best training exercises in the world! I was saved by this training later in my life, as fire fighter i remember being on a (working Fire) i remember puking in my scott airpak mask while in a burning building, as i started to tear at my mask …..the words and wisdom of my Senior Drill Instructor rang in my brain bucket….private Hodder if you remove that mask in combat you and your FIRE TEAM ARE DEAD!!! to this day i say a prayer for Senior Drill Instructor SSGT Payne Platoon 2065nov1st1978

  7. I have a question rather than a comment ……. if you have been in the gas chamber before with only a smaller amount given will it effect you more or less ? in meaning do you get use to it?

  8. The series of events listed above differ from my experience in the chamber. We did not apply and remove our masks 3 seperate times. We entered, went through a little introduction by the trainer, and then we were ordered to remove our masks and recite “Platoon 3031, Senior Drill Instructor Sgt. Hare”. Although “Pla” was about the only thing anyone could get out before the effects of the gas set in. Just thought I’d share that little bit of info since my experience was different from that listed above.

  9. The tear gas training varies depending on what year you went to boot camp. In 1974/1975 we didn’t have pour gas masks on when we enter the “chamber.” We all gathered around the hroom and after the pellet was fired up we had to wait a few minutes for the chamber to fill up. Once it did, we were instructed to say our name rank & SSN. After EVERYONE finished with that, we were told to put the masks on, clear them. We waiting a couple of more minutes them marched out of the chamber.

Leave a Reply

Your email address will not be published. Required fields are marked *