Fire extinguisher - hangar

ateamer

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ateamer
I need a fire extinguisher or two for our hangar (60x60 - one plane, one motorhome, workshop and storage). The usual dry chemical ABC type is not an option because it’s corrosive and impossible to clean up from aircraft (it flows into seams and rivet holes).

The biggest threat is a gasoline-fueled aircraft fire, followed by the usual garage/workshop fires. Note: Refueling anything - plane, mower, chainsaw - takes place outside the hangar.

From what I’ve read, the options for use on aircraft on the ground are Purple K, Halon or CO2. Any opinons, experience, advice on which one to get? I’d love to have the bucks for a wheeled 150-lb. Halon fore bottle, but most likely Halon in any size bigger than cockpit use is prohibitively expensive.

Can anyone confirm that Purple K is non-corrosive? My Google-fu is undergoing a weak spell and I had a hard time finding a definitive answer.
 
My opinion on the matter (not even worth .02) is that if I'm using a fire extinguisher on an aircraft, I'll figure out and deal with the corrosion problem later. I probably have bigger problems at the moment in the hangar than concerns of getting foam out of the rivets, like an aircraft burning to the ground. It just doesn't matter much if the plane is totaled.

But yes if you have the option to use a non-corrosive fire extinguisher that would be preferable, assuming it is just as good at putting out a fire.
 
The problem with CO2 extinguishers is that they are only B:C rated. If you have general combustibles that have already lit-off, you're going to need an A-rating as well. Halon is the same.

You need either a CO2 or Halon for the initial attempt, if you think you caught it while it is only fuel. Dry-chem as a follow-up if other combustibles got involved. Before you're reaching for a 2nd extinguisher you should be calling 911.
 
I need a fire extinguisher or two for our hangar (60x60 - one plane, one motorhome, workshop and storage). The usual dry chemical ABC type is not an option because it’s corrosive and impossible to clean up from aircraft (it flows into seams and rivet holes).

The biggest threat is a gasoline-fueled aircraft fire, followed by the usual garage/workshop fires. Note: Refueling anything - plane, mower, chainsaw - takes place outside the hangar.

From what I’ve read, the options for use on aircraft on the ground are Purple K, Halon or CO2. Any opinons, experience, advice on which one to get? I’d love to have the bucks for a wheeled 150-lb. Halon fore bottle, but most likely Halon in any size bigger than cockpit use is prohibitively expensive.

Can anyone confirm that Purple K is non-corrosive? My Google-fu is undergoing a weak spell and I had a hard time finding a definitive answer.

Purple-K is potassium bicarbonate, it's non-corrosive to aluminum (I'm trying to find references now). But it's proprietary, I think, and you usually can only get it from a fire extinguisher company that will inspect it once a year, or whenever. An alternative is sodium bicarb, baking soda. It will be inside things labeled "marine" or "kitchen". Both these are B:C agents (liquids/electrical).

A:B:C (solids/liquids/electrical) dry agents are usually monoammonium phosphate and are corrosive to aluminum. They flow into tight spaces and form a crust, where the other agents can be hosed out.

Look at the fuel island at the airport, or on the back of the fueling truck, you'll probable see Purple-K.

edit:

I can't find it now, but I know I was looking into this about 10 yrs ago. Back then I found something that was airport/aircraft related, but I can't find it now. ABC agents reach into aluminum and electrical systems and then melt and flow to smother the fire and remove heat. The residue, in the presence of moisture, forms some sort of acid compound that's bad for aluminum and electrical systems. You may put out the fire, but total the airplane. The Purple-K and sodium bicarb (B:C) agents work differently and can be washed out.

@midwestpa24 notes that you might need ABC in the hangar but also want BC for the plane.
 
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As an airport firefighter, I would recommend one of each. An ABC rated dry chemical extinguisher for most possible fires, and a Purple K extinguisher for any aircraft related fire. It is code for most hangars to have ABC for building protection even though it is known to be corrosive to aircraft.
 
I'm sure Matthew remembers the fire at OJC several years ago. My old helo cfi said something once that's stuck with me, that he regretted letting his partner talk him into having multiple uses for a building. They had a hangar, A&P shop, office space, and quarters for medevac crew. Even though the fire was discovered pretty quickly it spread even faster. Since then I've agreed with the notion that if you have a hangar, that's all it should be, a hangar.
 
I'm sure Matthew remembers the fire at OJC several years ago. My old helo cfi said something once that's stuck with me, that he regretted letting his partner talk him into having multiple uses for a building. They had a hangar, A&P shop, office space, and quarters for medevac crew. Even though the fire was discovered pretty quickly it spread even faster. Since then I've agreed with the notion that if you have a hangar, that's all it should be, a hangar.
And for a hangar fire...well, the extinguisher is there to give humans enough time to get out.
 
One type is not enough. A large CO2 for immediate action on a fire near the plane, pressurized water for non liquid fires, and purple K dry chemical for fires related directly to the plane.

The water ones are pressurized with either air or nitrogen, and refillable by you.

We once had a Franklin engine that was fond of barfing back through the carb, and setting a fire. We used a CO2, one short blast and it was out. The battery was not up to cranking until all the fire was drawn into the engine, and the carb air temp probe would melt if we were not fast.

Calling 911 should be first on the priorities, though, then talk to them as you fight the fire, phone in pocket. Time is of the essence, and powerful backup if you do not succeed immediately.
 
I'm a proponent of an extinguisher in the hangar. Most fires start small. Great if one can be caught early or impeded until the first responder's can arrive. I'd rather suffer the liability my my plane than be responsible for the hangar row going up. When you get sued, first opening comments from plaintiff(s) attorneys will be "Defendant was so negligent, didn't even have a fire extinguisher".
 
I have two ceiling mount halon/dry chem combo extinguishers that are fitted with "sprinkler head' type affairs. I 've got largish dry chemical extinguishers mounted on the wall as well.
 
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