SCBA Newbie question

[MadAxe]

Got an SCBA question for the firefighter/medics here that I hope someone can answer for me. I'm a complete newbie to SCBA but recently had the opportunity to get suited up in a B Level Hazmat suit with SCBA as part of a mock chem spill exercise. Both the suit and the mask were too small to fit me properly (they were the only ones available) but since it was just a training exercise we went ahead and got me and another responder suited up anyways.

The tenders had just finished taping the last of the seams around the hood and the mask, but hadn't hooked me up to the air supply yet. I had felt fine up to that point, but within about 90 seconds of being fully taped up (but with no air running) I started feeling really air hungry. My understanding was that one can breathe through the port on a mask without the air supply hooked up without any problems, so I chalked it up to nerves/excitement and made an effort to relax and breathe normally. That did nothing to help, and I started getting -extremely- air hungry. I could feel myself beginning to panic, so I signalled to the tenders that I wanted the hood off. As soon as I got the hood off I pulled the mask away from my face a bit, got a good breath of air, and felt fine again.

The incident got me wondering - should I have been able to breathe normally through the mask without the air supply running? For how long? I'm a big guy (powerlifter) and have a tidal volume way above average. I've had my lung capacity measured with a spirometer at just over 9L, which is about 1.5x the average, if that matters.

I've never had an anxiety attack or incident of claustrophobia in my life, but having treated other people going through them I'm wondering if that might not be the explanation for what I felt. All I know is that I was extremely uncomfortable, but would like to know why, and if it is going to be a potential problem for me in the future.

Apologies for the long-winded question (no pun intended).

[jbanagas]

Could have just been your nerves, but yeah you should be able to breath just fine without the air supply. i never done the Hazmat thing, but with stucture PPE's you can strap on your mask and breath without being hooked up to the bottle.

[Chief1C]

Usually when the bottle is off, and the regulator is hooked to the mask.. You can't breathe, unless you open the purge valve. I get the same way, if someone turns my tank off, it's a natural human instinct to panic when you cannot breathe - at all. However, I don't flip out, I just stick my finger under the edge of the mask, and breathe; or open the purge valve.

When you're hot, working hard, hurt all over, and you suddenly can't take a breath, no matter what kind of air it is. That's going to set off your brain, to think, I need to find a way to breathe NOW. I wouldn't be concerned, unless you have a panic attack every time you don an airpack. That could be a problem if the job requires you to work in dark, tight, low air quality environments.

[pguy280]

Here is my take on what happen. Who ever was in charge of your training excersise needs a dope slap. To put you into a hazmat suit and scba that were not properly fitted is crazy. To many peoplel DIE in training excises when safety is not the number one priority. I would say those are the factors that caused you to starve for air. There are trainbing standards for a reason. Your training coordiantor chose to ignore those standards and placed you in a position to fail.

To answer your question. You should be able to breathe through a properly fitted mask with the regulator disengaged from the face piece without problems.

[Richard B the EMT]

OK, the non rescue EMT has a question:

They put you into an SCBA, then into the "moon suit" without turning on the air supply? Unless I am missing something, and if I view this correctly, it is the equivalent of having your head held underwater until you almost passed out from lack of Oxygen. Those "moon suits", per what I have been taught, are not supposed to allow liquids or vapors in, including the 21% concentration of oxygen in room air, which is why the SCBA is worn inside the suit.

[MadAxe]

Thanks for the replies - much appreciated. The regulator was not hooked up at the time I started getting air hungry, I was breathing through the valve at the front of the mask. I was able to move air, just not enough of it to feel comfortable once I was all taped up and fully closed in - felt like I was breathing through a straw

In defence of the exercise co-ordinator, the tenders (also new to Hazmat) were a little over-eager in getting me fully suited up before the air tanks were ready to go. Also, I figure I'm at least partly to blame in that I probably should have spoken up before hand that the equipment wasn't really fitting me properly.

Thanks again.

[Arizonaffcep]

OK, the non rescue EMT has a question:

They put you into an SCBA, then into the "moon suit" without turning on the air supply? Unless I am missing something, and if I view this correctly, it is the equivalent of having your head held underwater until you almost passed out from lack of Oxygen. Those "moon suits", per what I have been taught, are not supposed to allow liquids or vapors in, including the 21% concentration of oxygen in room air, which is why the SCBA is worn inside the suit.

What u are describing is the the class A hazmat suit. The class B is similar, but the SCBA is worn exterior to the suit, with the "hoodie" portion of the head covering coming over the top of the mask of the SCBA, similar to the hood on a sweat shirt.

[mstovall]

As being a member of a very active hazmat operations team in the past, what you are describing in my opinion is the poor fitting mask. If the mask is too small, It will reduce your airway, thus inducing positional asphyxia. Head tilt CHIN LIFT is the standard way to open an airway. With a mask that is too small, you push the mandible into the airway. Combine this with then taping the face, thus reducing the ability to maintain additional motion, you probably were actually getting less air than you were used to. Thus the anxiousness. You were right in having them remove everything. As stated above, it is the overlooked small stuff that causes life ending accidents in training. This is also the reason you shouldn't just guess your size for an SCBA, especially when your life depends on it.

The other thing is always "Train the way you should act, and you will act the way you train. (or one of the other variations of this)" Basically when you half-ass something in training, then you are more likely to mess something up in the real thing, and a Hazmat scene is usually not very forgiving if you are in the red zone.

IMHO,

Michael

[toutdoors]

Madaxe, I would have to agree with previous posts in regards to the fact that you may have been a little nervous, then couple that with a facepiece that is too small, and you are well on your way to experiencing this problem. However, at times I find myself feeling as though I am not getting the same amount of air when I have my face piece on and not "on air" yet. It is something you will get used to, and come to expect. So next time, make sure you get fit tested for the proper size facepiece, and just relax, you will be surprised how much more comfortable you will be. If you continue to have the anxious feelings, inform the training officer, and ask for some more training with the SCBA. Prior to any type of training, you should be as familiar with that piece of equipment as you are with your own toothbrush, remember, it is your lifeline to quality air; demand the proper training. I have seen new recruits completely freak out when they get geared up on the apparatus floor for the first time, some make it through, and others don't. The big key is to simply relax, and remember you are just training (for now), have fun with it and it will come to you. Good luck.

Also, I agree with Arizonza, in regards to the hazmat suit classifications.

[Lone Star]

Having been a Firefigher for 15 years, I've worn both the chest mounted regulator style SCBA and the mask mounted regulator style.

You can breathe through b oth of them without turning the tank on, but the regulators cannot be hooked to the mask.

Once you hook the regulator to the mask, you've closed off the only 'breathing port' you have... and yeah, it DOES get 'scary' not being able to breathe!