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  #1  
Old 02-10-2010, 06:19 PM
Rigamarole Rigamarole is offline
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What does it feel like to get sprayed by a fire extinguisher?

Is it cold? Will it soak your clothes? Does it irritate the skin?

Is it painful, merely uncomfortable, or fun? Is it dangerous?

We can assume it's a standard ABC extinguisher. If the answers would change for other classes of extinguishers though, feel free to mention it.


(No, I'm not thinking of trying this. I just want to know for the sake of writer's curiosity)
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  #2  
Old 02-10-2010, 07:06 PM
brujaja brujaja is offline
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Humilating, in my case. It was an abusive boyfriend (the only one I've ever had, and not for long, either!) and he did it on his front porch.

As I recall, the stuff was irritating as it dried. It didn't really hurt when it happened, except the stuff is under pressure and it's, you know, invasive.

I think it was also pretty cold.
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  #3  
Old 02-10-2010, 07:17 PM
LSLGuy LSLGuy is offline
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Some fire extinguishers spray powder. Other spray liquids. Others spray gasses. Some spray CO2 as a rapidly evaporating liquid-to-gas.

What it feels like depends a bunch on how close you are, or saids another way, how forcefully it hits you. We're not talking rip-your-arm off forces, but a spray of powder, liquid, or gas in the eye could be injurious. etc.
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  #4  
Old 02-10-2010, 07:24 PM
Claude Remains Claude Remains is offline
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There are several types of extinguishers. My only prank encounter was from what is called a PKP when I was in the Navy. Its a dry purple powder that took my breath from me and blinded my for a minute. Good times.
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  #5  
Old 02-10-2010, 08:55 PM
Snnipe 70E Snnipe 70E is offline
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ABC would be dry chemical. It is an nonorganic powder. It does attack the liver if you get it into your system.
If you get it in your lungs it will dry the linning enough and it would make it hard to breath.
In the face it would dry the eye balls and nasil areas.
If you get it on your skin some would absorb some through the skin.

Pressurised water type is like getting hit with a large squirt gun

[B]CO2[B] Depending on how close you are. At the opening of the nozzle small particles of dry ice form along with a fog of frozen water. This is very cold and if close enough to your skin can cause a surface frost bite.


With the exception of the pressurised water your clothes would not get soaked. But it is a dangerous thing to do to some one.
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  #6  
Old 02-10-2010, 09:01 PM
Soul Soul is offline
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I got sprayed with a CO2 extinguisher once. It was cold and damp, and it had a smell to it that reminded me of a child's wading pool.
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  #7  
Old 05-09-2014, 04:04 PM
ebsh ebsh is offline
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Same experience

Just the other day, I was sprayed with a dry powder fire extinguisher by my boyfriend on his front steps . The powder felt terrible in my eyes and mouth, but it washed out of my clothes fairly easy. The drive home was tense, as i couldn't see too clearly. Luckily enough a long shower got rid of the rest of the powder. Some of it did get in my lungs, so they were raw for a couple days, but I recovered.
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  #8  
Old 05-09-2014, 06:37 PM
jayjay jayjay is offline
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And pressed charges, I'm hoping.
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  #9  
Old 05-09-2014, 09:54 PM
gotpasswords gotpasswords is offline
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So far, the score is one Navy prank with Purple K, and two cases of domestic violence on the front porch.

It just seems weird that the two "civilian" instances were done by abusive boyfriends in the same place, rather than drunk frat boys or some ill-advised bet.
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  #10  
Old 05-09-2014, 11:19 PM
AaronX AaronX is offline
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Yeah, odd coincidence. Is it common to have fire extinguishers in US homes?
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  #11  
Old 05-09-2014, 11:36 PM
flatlined flatlined is offline
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Quote:
Originally Posted by AaronX View Post
Yeah, odd coincidence. Is it common to have fire extinguishers in US homes?
Well, yes. There are 5 in our kitchen. There were only 3 before that time I set the curtains on fire.

We have one in all of our vehicles, and others are scattered around.

I don't pay attention to them, and I'm too lazy to get up and go count, but I'd guess that we own at least 25.

We also own a butt load of flashlights.

As to the OP's question, I have never been sprayed by a fire extinguisher. I do know a Merchant Marine who told me that they use their fire hoses to repel pirates. He used the term "whack a mole" when he was telling me about it.
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  #12  
Old 05-10-2014, 12:26 AM
Senegoid Senegoid is offline
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I can recount a lecture from a third party, which admittedly might be somewhat propaganda. When I was in junior high school, we had a fireman come by one day and give us "the talk" about fire safety, including some lecture about fire extinguishers. Here is what he told us about CO2 extinguishers:

It contains compressed CO2, which expands massively as it is discharged. Expanding gasses get very cold, and this will get cold enough to cause frostbite. (Here's an experiment you can do at home: Open your mouth wide and blow gently into the palm of your hand. Note that it feels warm. Now purse your lips and blow gently into the palm of your hand. Note that it feels cool.)

Now, remember how if you go out on an ice-cold day and touch a frozen lamp post, your finger will stick to it? (Or similarly, if you touch a metal ice cube tray fresh out of the freezer.) Did you ever play that game of touching your tongue to a frozen lamp post?

Next, consider that all the expanding CO2 rushing out of that funnel will generate static electricity. Lots and lots and lots of static electricity. When enough builds up, you will get a sudden very strong jolt.

Now, have you connected the dots yet? If you aim the CO2 discharge by holding the funnel, it will get icy cold and the skin of your hand will freeze onto the funnel. Then you will get a huge static electricity jolt, and your arm will jerk away.

Leaving the skin from the palm of your hand on the funnel.

THEREFORE: Note that all CO2 extinguishers have, or ought to have, a wooden or plastic ring around the base of the funnel, which is where you should hold it to aim it. Here is the best pic I could find showing this. It is really really important for you to know and remember: HOLD THE FUNNEL BY THIS RING WHEN YOU DISCHARGE IT!!!!! Read the instructions on the side of the extinguisher in that picture -- it even says so, although not quite as emphatically as it probably should.

ETA: So, fire extinguishers are the weapon of choice now for use by abusive boyfriends?

Last edited by Senegoid; 05-10-2014 at 12:29 AM..
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  #13  
Old 05-10-2014, 12:33 AM
Senegoid Senegoid is offline
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Okay, here's the best picture I could quickly find, showing someone actually using a CO2 extinguisher. Notice how he's holding the funnel by the "handle" at its base.
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  #14  
Old 05-10-2014, 07:36 AM
enipla enipla is offline
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My brother and I had a play fight with them once. The dry type. I think it had just rained and a bunch of it got stuck to his car and screwed up the finish a little bit.
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  #15  
Old 05-10-2014, 07:58 AM
AaronX AaronX is offline
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Huh, and my friends looked at me as if I were mad when I wanted to bring a fire extinguisher on our road trip.
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  #16  
Old 05-10-2014, 08:46 AM
BrotherCadfael BrotherCadfael is offline
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Back when I was running rescue, a chemical fire extinguisher in the back of the ambulance fell over. For some reason, this extinguisher had a Lexan pin, instead of the more durable steel pin. The extinguisher fell over, the pin broke, and the extinguisher started to discharge its contents. Vigorously.

Fortunately, there was no patient in the back, as the unit was on its way back to the garage. The EMT in the back, under the assault of the chemical powder, exited the side door while the unit was still moving. She said she couldn't' have stayed in the back of the ambulance for even five more seconds.

It took about a week to fully clean the back of the ambulance.
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  #17  
Old 05-10-2014, 07:46 PM
gotpasswords gotpasswords is offline
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Quote:
Originally Posted by AaronX
Is it common to have fire extinguishers in US homes?
Absolutely. I give them as home warming or wedding presents.
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  #18  
Old 05-10-2014, 09:02 PM
Sailboat Sailboat is offline
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Some teenagers in our area drove around spraying random passersby with a fire extinguisher. Apparently the type they used is powered by chemical reaction that produces acid. As the thing ran out of fire retardant, the acid came out, and they failed to notice they were driving around spraying acid on people.

They were charged.
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  #19  
Old 05-10-2014, 09:14 PM
Lord Feldon Lord Feldon is offline
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Quote:
Originally Posted by AaronX View Post
Yeah, odd coincidence. Is it common to have fire extinguishers in US homes?
I found these claimed statistics:
Less than 5% of homes. (PDF)
25% of kitchens
75% of homes.

So, fire extinguishers are either super-common or really weird.
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  #20  
Old 05-12-2014, 07:08 AM
Machine Elf Machine Elf is offline
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Quote:
Originally Posted by Senegoid View Post
(Here's an experiment you can do at home: Open your mouth wide and blow gently into the palm of your hand. Note that it feels warm. Now purse your lips and blow gently into the palm of your hand. Note that it feels cool.)
Adiabatic cooling is a real thing, and does indeed explain why CO2 fire extinguishers spit out a mix of dry ice and freezing-cold gas. However, the experiment you describe above is not a good demonstration of adiabatic cooling. You can't develop enough of a pressure drop across your pursed lips to result in a noticeable temperature drop. Instead, what you are demonstrating is an increase in convection: in the first scenario the large, slow-moving plume of air from your mouth surrounds your palm with warm, moist breath, whereas in the second scenario the narrow, the fast, narrow jet of air from your pursed lips entrains more of the cool ambient air and moves it across your skin, resulting in heat loss.

According to this chart, the maximum pressure a "typical" person can exert during exhalation is about 1.4 psi above ambient. The equation for adiabatic processes indicates that if the air in a person's respiratory tract is at 98.6 degrees while at this pressure, then when it comes out of your mouth, it'll be at 84.3 degrees. So it's possible to create a measurable cooling effect this way, but only by blowing as hard as you can through pursed lips; blowing gently, as you described, will not create nearly this much pressure (and not nearly this much temperature drop).
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  #21  
Old 05-12-2014, 04:42 PM
Cartoonacy Cartoonacy is offline
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Quote:
Originally Posted by Senegoid View Post
It contains compressed CO2, which expands massively as it is discharged. Expanding gasses get very cold, and this will get cold enough to cause frostbite. (Here's an experiment you can do at home: Open your mouth wide and blow gently into the palm of your hand. Note that it feels warm. Now purse your lips and blow gently into the palm of your hand. Note that it feels cool.)

The Master comments.

Specifically:

Quote:
Originally Posted by Cecil Adams
Suffice it to say no one believes you can pressurize air significantly by puckering your lips.
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  #22  
Old 05-16-2014, 03:04 PM
ebsh ebsh is offline
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It was walter.
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