Fire extinguisher

[Rob M.]

Re: Fire extinguisher

I work in a room that is chuck full of computers, with a false floor for the wires to them. There is a Halon (followed by four numbers that I do not remember even though I pass a sign with them on it every time I enter the room) system in that room and the wire space under it. The tanks for that Halon are about five feet tall and three feet in diameter, and there are five of them. Every time I see the doors open to them I want to take a picture for you guys, but no photos are allowed at work, so I have to do it on the sly and that is not so easy.

Terry,

Be sure to leave the room ASAP when those tanks are releasing their content because otherwise you will certainly die due to lack of oxygen...

[Richard M.]

Re: Fire extinguisher

Years ago I had a engine fire in my '59 due to a flood condition in the secondary(front) carburetor of my stock 2x4 270 hp, when a backfire in the primary occured. I carried a small Halon FE in the seat separator(glovebox) at all times.

Fortunately it was a calm day with no wind. When I opened the hood the flames totally surrounded the 2x4 air cleaner, rising a few feet above it. In a circular motion the halon immediately extinguished the fire.

I was lucky it was not windy that day as I have learned from a retired firefighter, of 30 years experience, that halon is ineffective in windy conditions. He recommends that any time halon is used in a engine fire, if windy conditions exist, it is best to exhaust the halon FE from under the car up and into the engine bay.

I always carry a Halon 2.5 lb FE in old cars. This is mandatory in my wife's 2 V12 Jaguars, as the 4 carburetors in the '72 E-Type reside directly above the exhaust manifolds, and her '91 XJS with Marelli dual coil ignition has a design flaw which could disable one engine bank of the electronically injected fuel system to continue to pump unburned fuel into the exhaust system, comprised of piping components shaped much like a U-trap under your kitchen sink. Fuel can puddle there and be ignited. She knows well if she's ever out and about, and looses 1/2 of the engine power, to immediately pull over, shut it down, get out of the car, and call her mechanic.(me)

Rich

[Terry M.]

Re: Fire extinguisher

Terry,

Be sure to leave the room ASAP when those tanks are releasing their content because otherwise you will certainly die due to lack of oxygen...

Rob, we have regular, and sometimes irregular, fire drills. The gist of the sign with the Halon 1301 (even though I passed the sign twice earlier this morning, I had to go look as I typed this) relates to your cautionary warning. I know where the nearest exit door is, and I could get there in the dark – even though we have four separate sources of power so dark is highly unlikely. I know the Halon is for the computers and not for the people. We often joke about that here.

When I worked in the field we had very large rooms that were fire protected by CO2 (not for computers, but for indoor transformers). I once had the opportunity to watch a test of one of those systems. The room was filled over five feet deep ( I actually don’t know how deep it got because the window in the door was at about 5 feet and I lost sight of the top) with snow that rapidly disappeared.

I once had the opportunity to be on scene when the Chicago Fire Department decided it was wise for them to empty a 10-wheel truck mounted dry powder system into one of our facilities that had a relatively minor fire going on. The powder was knee deep in the room and one could wade through it, as if it were water. That was one of the weirder situations I ever found myself in -- and there were lots of weird situations in my several decades in the field.

Thanks for your wise advice.

[Michael J.]

Re: Fire extinguisher

The best thing about Halon, and why it is used in so many commercial industrial applications (besides the cleanliness of it), is that it is 5 times heavier than air. In many situations in my old business (oil and gas industry) the burning material was always low and isolated, so the Halon sank quickly, surrounded and smothered the fire immediately without disturbing the burning material and spreading it around.

[Terry M.]

Re: Fire extinguisher

The best thing about Halon, and why it is used in so many commercial industrial applications (besides the cleanliness of it), is that it is 5 times heavier than air. In many situations in my old business (oil and gas industry) the burning material was always low and isolated, so the Halon sank quickly, surrounded and smothered the fire immediately without disturbing the burning material and spreading it around.

Michael,
Many petroleum products have fumes heavier than air also, so you got double protection with Halon in your situation. If there is much wind the Halon can be less effective than it might otherwise be. I have never inquired where the nozzles for the system here are. I assUmed they are in the ceiling, but there may be nozzles in the under floor where all the wiring is. There might even be several zones. That stuff is no longer in my job description. All I have to do is Adios when necessary.

Last week there was a natural gas leak near one of the elementary schools in the district where my daughter teaches. The school is three stories plus a basement and all floors have classrooms. Some rocket scientist told them to evacuate the second and third floors. A short while later the ambulances came for the teachers and children in the basement. They were treated and released from the hospital and so far nothing more than major headaches, but doesn't everyone know that natural gas fumes are heavier than air? I wonder what happened to all those science classes they teach. Even my daughter looked at me funny when I told her NG is heavier than air.

[Michael J.]

Re: Fire extinguisher

Michael,
Many petroleum products have fumes heavier than air also, so you got double protection with Halon in your situation. If there is much wind the Halon can be less effective than it might otherwise be. I have never inquired where the nozzles for the system here are. I assUmed they are in the ceiling, but there may be nozzles in the under floor where all the wiring is. There might even be several zones. That stuff is no longer in my job description. All I have to do is Adios when necessary.

Last week there was a natural gas leak near one of the elementary schools in the district where my daughter teaches. The school is three stories plus a basement and all floors have classrooms. Some rocket scientist told them to evacuate the second and third floors. A short while later the ambulances came for the teachers and children in the basement. They were treated and released from the hospital and so far nothing more than major headaches, but doesn't everyone know that natural gas fumes are heavier than air? I wonder what happened to all those science classes they teach. Even my daughter looked at me funny when I told her NG is heavier than air.

[Jim D.]

Re: Fire extinguisher

Last week there was a natural gas leak near one of the elementary schools in the district where my daughter teaches. The school is three stories plus a basement and all floors have classrooms. Some rocket scientist told them to evacuate the second and third floors. A short while later the ambulances came for the teachers and children in the basement. They were treated and released from the hospital and so far nothing more than major headaches, but doesn't everyone know that natural gas fumes are heavier than air? I wonder what happened to all those science classes they teach. Even my daughter looked at me funny when I told her NG is heavier than air.

And rightly so. Natural gas is LIGHTER than air and dissipates quickly. Propane is heavier than air. The specific gravity of air is 1, Propane is 1.52, Natural Gas is .7

[Michael J.]

Re: Fire extinguisher

True enough, air is primarily nitrogen, which has an atomic mass of 14, but in air, it is an N2 molecule, which has a molecular mass of 28, while CH4 is 16.

[Steven B.]

Re: Fire extinguisher

Michael,
Many petroleum products have fumes heavier than air also, so you got double protection with Halon in your situation. If there is much wind the Halon can be less effective than it might otherwise be. I have never inquired where the nozzles for the system here are. I assUmed they are in the ceiling, but there may be nozzles in the under floor where all the wiring is. There might even be several zones. That stuff is no longer in my job description. All I have to do is Adios when necessary.

Last week there was a natural gas leak near one of the elementary schools in the district where my daughter teaches. The school is three stories plus a basement and all floors have classrooms. Some rocket scientist told them to evacuate the second and third floors. A short while later the ambulances came for the teachers and children in the basement. They were treated and released from the hospital and so far nothing more than major headaches, but doesn't everyone know that natural gas fumes are heavier than air? I wonder what happened to all those science classes they teach. Even my daughter looked at me funny when I told her NG is heavier than air.

In communications we used halon in the central offices to protect the switches/computers/cables, generator and battery rooms, etc. While sizing a project with Ashland Oil shooting RF, halon was used to protect the enclosed areas we targeted. We also used halon in the labs. Expensive but it works. Terry, all of our bottles were installed at ceiling height with the nozzles on the bottom of the bottles

Steve.

[Gary B.]

Re: Fire extinguisher

...Every 5 years a contract service company replaced the CO2 extinguishers. I believe they serviced them at their shop and returned them to us...

Now that everyone has me worried about the health of my C02 extinguisher, is there a comparable concern about Halon or H3R extinguishers? If the needle still points to the good wedge in the dial on my H3R unit, can I assume the extinguisher doesn't need to be inspected or serviced even though it might be 10 years old?

Back to my CO2 unit, I vaguely recall that the vendor I bought it from said it had to be emptied, water pressure tested and refilled every X years in order to be officially approved for use, but I can't remember if X was 5 or 10. Does anyone know?

Gary

[Jim D.]

Re: Fire extinguisher

Back to my CO2 unit, I vaguely recall that the vendor I bought it from said it had to be emptied, water pressure tested and refilled every X years in order to be officially approved for use, but I can't remember if X was 5 or 10. Does anyone know?

Gary

They need to be hydro tested every 5 years.

[Gary B.]

Re: Fire extinguisher

They need to be hydro tested every 5 years.

Jim,

I just got a quote for $52.50 to have my 5 lb CO2 unit hydro-tested and refilled. That's a definite downside to owning a CO2 extinguisher.

Gary

[Jim D.]

Re: Fire extinguisher

Jim,

I just got a quote for $52.50 to have my 5 lb CO2 unit hydro-tested and refilled. That's a definite downside to owning a CO2 extinguisher.

Gary

If it's for your home use, I wouldn't worry about it. If it has a gauge, tap on it to make sure the needle isn't stuck and make sure it reads full. If no gauge, the neck of the extinguisher will be stamped with a "full" weight and an "empty" weight. Yours will have a 5 lbs. difference. Weigh it on a scale to see if it's full.

[Gary B.]

Re: Fire extinguisher

Jim,

My unit has no gauge, but in the space at the base of where the top inserts into the tank, where it says Full Wt, there's nothing stamped there.

Gary

[Jim D.]

Re: Fire extinguisher

Jim,

My unit has no gauge, but in the space at the base of where the top inserts into the tank, where it says Full Wt, there's nothing stamped there.

Gary

In my 31+ years in the industry, I've never seen one that didn't show the full & empty weight. Someone screwed up and now you have no idea whether it's full or empty. If you end up having it hydro tested, have whoever re-fills it put the correct stamping on it.