CHEMOX vs Drager SCBA

[FSTO]

CHEMOX never bothered me.  As a young Reservist, I once spent an entire summer at the DC School wearing one for several hours, virtually everyday.  I became so adept at using it that I could put it on and have air flowing faster by myself than if someone was trying to "help" me.  I also usually did this without using the quick start candle.  One of the big advantages I felt was that with everything in front, one could move around much easier in a shipboard environment.  I even managed to get through an escape hatch without collapsing the lungs - and I'm a big boy.  The only real advantage I saw in the Scott Pack was that the air tended to be cooler and "taste" better.

Your arms must be longer than mine. I constantly collapsed my lungs. I doubt if I ever fought a fire with the chemox working.

 

[jollyjacktar]

Once the guy who made the quick start candles retired the canisters became rather sketchy and dangerous. There were more than one incident at the school where students and staff had close calls. Plus the lungs must have been breeding grounds for god knows what.

 

[Scott]

Once the guy who made the quick start candles retired the canisters became rather sketchy and dangerous. There were more than one incident at the school where students and staff had close calls. Plus the lungs must have been breeding grounds for god knows what.

Never worn the device, but heard loads of stories.

We have a CBRN approved hood with attached filters now rated to 5000 ppm H2S, but something tells me if push came to shove, I'd want positive pressure any day of the week.

Then again, I cut my teeth on 2As and moved to early generation 2.2 and onward to several other makers - so I have always been a cylinder guy.

 

[jollyjacktar]

I was witness to one of the sets catching fire while strapped to an instructor.  They were just able to cut it off him before it really went south.  Nothing says "holy shit" like one of those things going Chernobyl on your body.

Now that being said, they were fantastic when set against what they had before, which was SFA.

As for lungs, l was frequently collapsing mine and always at the worse possible time.  I'm glad they're gone for good.

 

[dimsum]

Your arms must be longer than mine. I constantly collapsed my lungs. I doubt if I ever fought a fire with the chemox working.

Yes.  I always wondered why the lungs were in front rather than on the back.  Even though I have no chance of using it again, I'm glad they're gone.

 

[NavyShooter]

I have a CF-98 on my file from WUPs in 04 on STJ.  We had multiple cannister failures - instead of producing oxygen, they were producing chlorine.

*not fun* to get a blast of Chlorine gas in your face when you are expecting oxygen.

 

[Navy_Pete]

Yes.  I always wondered why the lungs were in front rather than on the back.  Even though I have no chance of using it again, I'm glad they're gone.

They were designed to provide air to miners escaping from a collapse; think it's on the front so you can crawl out on your hands and knees.  Of course, they had cages around the lungs to prevent them collapsing.

Had one with a tear on one lung, so we cut it open out of curiousity; it was full of mold and all kinds of crap.  Glad they are gone, they were never meant for repeated use, but guess they were better than nothing.

 

[Furniture]

Here's a question then, if you can indeed answer it without giving something verboten away: do you guys have to wait for a full muster before setting something like a Halotron or CO2 system off?

Didn't see this answered earlier, with Halon the system is activated and a pipe is made, with AFFF the spaces is checked before activation. The attack team will clear the space as much as possible visually, and with the TIC looking for casualties. Every effort is made to ensure nobody is in the space short of a verification muster when AFFF is used.

 

[Pusser]

Your arms must be longer than mine. I constantly collapsed my lungs. I doubt if I ever fought a fire with the chemox working.

The trouble that I witnessed most often at the DC school with collapsed lungs came from wearing the set too low.  The key was to wear it so the canister was high on the chest (i.e. with your chin only about 4" above it.). It was also more comfortable up there and easier on the back.

 

[Pusser]

I have a CF-98 on my file from WUPs in 04 on STJ.  We had multiple cannister failures - instead of producing oxygen, they were producing chlorine.

*not fun* to get a blast of Chlorine gas in your face when you are expecting oxygen.

Admittedly, my chemistry is a little rusty, but I don't that's chemically possible.  Chemox uses potassium superoxide (KO2), which when combined with water (i.e. from your breath) produces a "breathable mixture" (containing oxygen).  Using normal chemical processes, you cannot create an element (which chlorine is), nor can you separate it from a compound if it doesn't contain that element in the first place.  Therefore, those canisters that malfunctioned were not producing chlorine.  That's not to say they weren't over producing something else unpleasant (hydrogen peroxide is produced in the normal chemox process), but it wasn't chlorine.

It's worth noting that potassium superoxide is also used in oxygen generators used in submarines and spacecraft and has even had limited use in some underwater rebreathers.

 

[NavyShooter]

Chemically, I would agree.  Which is why the OS who had it happen to him first wasn't strongly believed by myself (MS) or the PO2 who was present in the Aft ERT.  So, the PO2 supervised me, step by step, properly checking, and donning the Chemox.  We inspected the canister, installed, closed the bale, and yes, I got what smelled like Chlorine in the face.

How?  I'm not a chemist, but it happened.

More than just me as well.  There was a good lineup of us outside sickbay.

 

[Pusser]

I can't tell you what you smelled, but unless the canisters had a severe manufacturing defect (e.g. filled with a completely wrong substance), what you smelled was not chlorine.  It is in no way possible to extract chlorine gas from potassium superoxide.

 

[NavyShooter]

I agree - but Chlorine is what I smelled.

Same with the OS.

Along with the PO2 who supervised me.

Along with others on the ship who encountered canisters from the same batch.

Contaminated canister?  Manufacturing defect?  Don't know. 

I do know what Chlorine smells like though.

NS

 

[Pusser]

Just because something smells like something, doesn't mean it is that thing.  Sarin smells like "new-mown hay," but it most definitely is not!

 

[Navy_Pete]

If there were a number of canisters at once, was probably from the same batch with some kind of contamination during the manufacturing process.  There may have been some impurities or something that released a bit of chlorine (maybe simple table salt ionizing and off gassing?); unfortunately it can happen by something as simple as not cleaning out the equipment properly in the manufacturing line.

Once made straight chlorine gas by accident in a lab by not following instructions closely enough and caught enough of a whiff for it to hurt (that was with a fume hood).  On the plus side, you can smell chlorine at doses far lower than what is harmful, but if you had gotten a lungful at a high enough concentration, you would have been foxed, so it's unlikely it would have been the wrong chemical all together (that would have just killed you).