My Experience at the BMT Gas Chamber

BMT The Gas Chamber

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Even though you won’t experience the gas chamber until Week 4, a lot of people fear this part of Basic Training the most. I’m here to tell you… it’s not that bad.

BMT The Gas Chamber

CBRN training (pronounced C-Burn) is the actual name of the gas chamber experience. It stands for Chemical, Biological, Radiological, and Nuclear training. You will spend a whole day learning about these respective types of warfare and how to properly protect yourself against them.

The day will start with you getting on a bus and riding over to the training area. If you’re at BMT in the summer, this day will royally suck for you. Anywho, you’ll get off the bus and sit through some lectures on the different types of warfare and why America doesn’t employ them. It’s because they’re really bad and do horrible things to people. Think Anthrax and the Atomic Bomb.


MOPP GEAR. You’ll love to hate it. You won’t understand this until you actually take the class, but you’ll never forget it once you hear the tune. That little diddy will help you remember the order you’re supposed to put your gear on.


You’ll laugh about this later. The different MOPP levels and alarm codes will tell you what to do when under CBRN attacks. You will learn all this and more at CBRN training. Just do what they tell you and you’ll be fine.

Tips when putting on the mask: The mask is the hardest thing to put on because they freak you out about gas seeping into it. I ended up having mine way too tight and it was painful to wear and difficult to get off in the gas chamber. Make sure your mask is snug, but don’t let it cut off your circulation. If it’s snug, you’ll be fine. No gas will seep in.


Once you learn everything you need to know, you’ll have lunch. This is where you’ll eat your first MRE (if you haven’t already had to eat one). After lunch, it gets real. You’ll pack all your gear into your green bag and head to the chamber. Try to be near someone you like, as they’ll be your buddy for the buddy checks. They’ll be the one helping you put on your mask. Be quick and do what you’re told. The sooner you get your gear on, the sooner you get in line. The first couple of groups in the chamber have it the easiest. This is because the gas gets stronger as it builds, because even though they open the doors to let you out, the gas does not filter out completely.

There are several different chambers, and you line up in twos outside the door. When they open it, you’ll file in around the edge of the room. Once you’re inside, they explain what gas they’re using (basically tear gas) and what you are expected to do. This is when you’ll find out if your mask is on properly. If it isn’t, you will smell the gas immediately. You can either wait it out, or tell the instructor and they will let you out. However, you will have to go back and do it again on another day.

We had to do 25 jumping jacks. Then we were instructed to take off our hoods off. Some men can begin to feel a slight tingle because they can feel it on their neck. Most girls with long hair didn’t feel anything though. After that, they’ll tell you to loosen your mask. Everything moves pretty quickly.

Once you loosen your mask, they tell you to take it off and put it to your chest. Be quick about it. You can’t move on to the next step until everyone does this, and if someone else is slow, you’re suffering. If you don’t do exactly what they say, you’ll be standing in the gas for longer than necessary.

Once everyone has their masks off, you’ll be required to say your reporting statement. Sir, Airman Patten reports as ordered. I’ll be honest, the gas is not that bad. Some people are affected worse than others. I remember thinking “Is this it? This really doesn’t hurt.” Some people gagged and coughed a lot, but only my eyes watered.

When the reporting statements are over, they will open the door and you will file out slowly. If someone starts pushing or acting crazy, they will have to repeat CBRN, and they’ll be in for an ugly evening with the MTIs.


As you walk outside, they’ll remind you to hold your mask in one hand and your arms away from your body. Do not touch your face. You’ll walk around a big rectangle area two times. This allows for the gas to dissipate so it doesn’t burn you when you go to touch your face and other areas of your body. Once you’ve made the two laps, you’ll start removing your gear.

Once you’ve made it through, you’ll get to watch other people coming out of the chambers. It’s pretty funny. Then you’ll head over to the cleaning stations where you’ll wash your masks with water and some chemicals. Once that’s done, you’ll head back to the building where you were lectured, return all your items except your suit (you’ll need it during BEAST), and then wait for bus to pick you up.

My biggest piece of advice for this part of your journey is to stay calm. Do not freak yourself out. That’s what I did and I was nearly petrified from fear. Just relax, embrace it, and know that millions of other military members have went through this and survived. 

You’re gonna do great! Let me know if you have any questions.

14 thoughts on “My Experience at the BMT Gas Chamber

    1. There’s not much you can do to prep for the gas chamber except to get a good buddy who knows how to get the gear on faster. You want to be within the first two sets of groups that go in. The further back in the line you are, the stronger the gas gets as groups move through it. I was in the second group to go in and I didn’t think it was bad at all. We all psyched ourselves up about it way more than we should have. It’s over in 10 seconds. Good luck!!

      1. I only went one time, but I’m sure it doesn’t change on a daily basis. It is what it is. They make it all happen in one day.

    1. So, my experiences are based solely off Air Force Basic Training. I don’t know what it is like for Army basic. I don’t know what the situation is like down there, but I do know the gas chamber experiences are similar. I’m sure they’ll let you know everything you need to know.

Tell me what you think!