Fire Engineering Training Community

Where firefighters come to talk training

Hey group!
What do you think about wearing street clothes instead of tyvex suits under your Level "A" protection. I am worried about the 3's degration, permeation, and pentration. Now there saying that there is no need for the extra protection.
Let me know what you think!

Views: 319

Replies to This Discussion

Excellent I read the same article......... If you go on my web page at and then training page then to training question of the day. you will see the same question answered by a cali chief steve raney... let me know what you tihnk about what he said about it...... I agree with you both........ I also like to get the max protectio that I can get........
Thanks for adding me as a friend keep in touch let me know if you have any hazmat stuff for me ..... my email is
Hi group,
I have to agree. I want to most protection possible when messing with methel ethel billy bad stuff. I understand rapid deployment; however we have learned by time test results that rushing in to save the world is a good way to get hurt or dead early ourselves. The time it takes to get a tyvex suit on is not going to lessen our ability to mitigate the situation to a great degree. Thanks for inviting me to the group. I am also a lurker on ya'll might enjoy that group as well. It touches on FF stuff from time to time. Everybody be safe
Thank you for your reply and I must say the more I think of pretection I must agree with you. This is the greatest job in the world, let's pretect our self as best as we can so we can do for as long as we can.
Let me say this, the best protection is detection! Utilize your monitoring equipment to set your PPE levels. Many times a Level A is unnecessary and can be more dangerous than it is worth. We wear "street clothes" all the time with out incident. If you are worried about the "3's", I think you are in the product for way to long. We have to get out of the "sky is falling" mentality for haz mat. Let me know if you would like for me to explain this concept further.
Marty: For the groups sake please by all means go in depth-Todd
Ok, lets start by looking at the Level A. It's our highest level of protection. Most of the breakdown times are around 300 minutes or so for the newer suits. We dont have enough air to last that long and along with the heat stress that is inherent with that suit we have plently of protection without the tyvek or flash protection for that matter. We do not reuse our suits, they are thrown away after an actual entry.
On the flash protection issue, this is a plastic suit - think srink wrap. The flammable enviornment must be changed before entry in level A. Structural firefighting gear is the best protection for a flammable.
On an unidentified product, we do recon in turnout gear. We utilize our meters to determine if it is safe and also to classify product type; flammable, corrosive, radioactive, toxic.
The one thing I use level A for is acid gases, which is what the suit is intended for in the first place. Also, after I know what I am dealing with, may consider level A if I have to work in the product with the chance of getting the product all over me.
We have to have a good understanding of chemistry, there are things a chemical will and wont do.
I don't agree with the "level A for any unknown". There are no unknowns- its either a soild, liquid, or gas. SCBA is the best level of respriatory protection, as long as our airway is protected, we could go nude (for most incidents), just stay out of the product and you will be fine.

Now I will agree that there are some "exotic" animals out there, but what are the chances of seeing those? Gases make up less than 5% of all releases, soilds and liquid make up the majority. Of those, corrosives and flammables are the most common.
On the detection issue, if the book says "evac 7 miles" and the meter only hits 7 feet away from the product, which one is easier to deal with? Chris Hawley has some great books out on Air Monitoring and Risk Based Response check those out.
Kinda got off on a tangent here, but hopefully this is "clear as mud".
Thank you
I agree with Marty completely: Utilizing our Brain and tools i.e. monitoring equipment, research material etc. First determine if Level A is needed, then check your suit compatibility charts to determine permeation data. Then check the tag that is attached to the level A suit bag and see when it was last tested. A team should be at least testing their suits on an annual basis.

I just can not see where a tyvex suit is needed under a Level A suit. If people are doing this; try this experiment the next time you train, after the person exits the suit take his vitals to include body temperature, then do a little research as to what elevated core temperatures do to the human body.

Just a couple of other comments:

Look thru the NIOSH and mark down all the chemicals that cause death or serious injury due to skin contact, then compare them to the Level A suit permeation Data.

The Level A suit was designed with the understanding the wearer will be dressed in normal everyday clothes made from ordinary fabric.

I would suggest to those that have doubts about their PPE to attend a free course offered by DHS in Anniston Alabama there you will enter into an atmosphere containing several hundred lethal doses of nerve agent in Level C protection and you will leave with no adverse effects.

One last thing: A Level A suit is made up of many different layers (some have 21 or more) of material if the HazMat we were to encounter permeated all these layers before we ran out of air how in the world would one layer of saran wrap (tyvex suit) save our skin. Someone please show me the data.


Policy Page


The login above DOES NOT provide access to Fire Engineering magazine archives. Please go here for our archives.


Our contributors' posts are not vetted by the Fire Engineering technical board, and reflect the views and opinions of the individual authors. Anyone is welcome to participate.

For vetted content, please go to

We are excited to have you participate in our discussions and interactive forums. Before you begin posting, please take a moment to read our community policy page.  

Be Alert for Spam
We actively monitor the community for spam, however some does slip through. Please use common sense and caution when clicking links. If you suspect you've been hit by spam, e-mail

FE Podcasts

Check out the most recent episode and schedule of

© 2023   Created by fireeng.   Powered by

Badges  |  Report an Issue  |  Terms of Service