Q. Canadian Homebuilt: Fire Extinguishers - Halon

Hello All,

This question is regarding Canadian regulatory issue with importing a Halon
fire extinguisher.

I'm building an RV and am considering fire extinguisher options. Was about
to buy a Halon 1211 2lb fire extinguisher on ebay until I looked up the
legalities of importing it to Canada. Seems you can't anymore, even if it is
recycled Halon.

I know of homebuilders who use household CO2 fire extinguishers. However,
these devices, if discharged in a closed space will:

- decrease or obscure visibility
- reduced breathability wrt Halon discharge
- by-products can corrode aluminum if not cleaned off promptly (discharge
remains in faying aluminum layers.

The cheap household brands will self discharge in storage if the compartment
gets too hot (e.g. bubble canopy, on the ramp, standing in the sun).
Possible replacement for Halon is Sapphi
http://www.tyco.com/tyco/press_relea...l.asp?prid=718
however, I have not seen specific applications for aviation.

By the way, in Canada we are required by Transport Canada to carry fire
extinguishers in homebuilts.

What type of fire extinguishing agent to you use or plan to use? Looking
for comments and suggestions from Canadians as well as others familiar with
this issue. Thanks.



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References:



http://www.cbsa-asfc.gc.ca/E/pub/cm/...d19-7-2-e.html

In summary, the above regulations says:
5. The Ozone-Depleting Substances Products Regulations prohibit the
importation of:

d) any of the following products that contain any chlorofluorcarbon
or bromofluorcarbon from a place outside a party to the Montreal Protocol:

(3) fire extinguishers;




Transport Canada does not recommend replacement of Halon for aircraft:

http://www.tc.gc.ca/CivilAviation/co...ars/AC0179.htm

"to date none of these agents have been approved as a substitute for Halon
hand-held fire extinguishers used on board aircraft."

"RV9" wrote in message
...

I know of homebuilders who use household CO2 fire extinguishers. However,
these devices, if discharged in a closed space will:

- decrease or obscure visibility
- reduced breathability wrt Halon discharge
- by-products can corrode aluminum if not cleaned off promptly (discharge
remains in faying aluminum layers.

I think you may be confusing a CO2 extinguisher with a dry chemical
extinguisher. A CO2 extinguisher has no by-product other than the moisture
in the air which may be frozen by the expanding CO2. A dry chemical
extinguisher may leave corrosive residue.

You say that you are required to carry an extinguisher. I assume that the
regulation specifies the minimum rating of the extinguisher - if not the
agent. If the rating is specified and 1211 Halon is not available (try a
marine store), I would get a dry chemical extinguisher of the minimum rating
and carry it. Whether you use it or not will be apparent when the time comes
and you will easily be able to choose between corrosion and the effects of
the fire.

With my wooden airplane, I carry a small 1211 Extinguisher which I bought at
a garage sale. If the airplane catches fire, and there is dirt nearby, I
will toss the extinguisher into the fire and make tracks in the dirt.

Rich S.

On Fri, 15 Jul 2005 12:36:52 -0700, "Rich S."
wrote:

"RV9" wrote in message
...

I know of homebuilders who use household CO2 fire extinguishers. However,
these devices, if discharged in a closed space will:

- decrease or obscure visibility
- reduced breathability wrt Halon discharge
- by-products can corrode aluminum if not cleaned off promptly (discharge
remains in faying aluminum layers.

I think you may be confusing a CO2 extinguisher with a dry chemical
extinguisher. A CO2 extinguisher has no by-product other than the moisture
in the air which may be frozen by the expanding CO2. A dry chemical
extinguisher may leave corrosive residue.

You say that you are required to carry an extinguisher. I assume that the
regulation specifies the minimum rating of the extinguisher - if not the
agent. If the rating is specified and 1211 Halon is not available (try a
marine store), I would get a dry chemical extinguisher of the minimum rating
and carry it. Whether you use it or not will be apparent when the time comes
and you will easily be able to choose between corrosion and the effects of
the fire.

With my wooden airplane, I carry a small 1211 Extinguisher which I bought at
a garage sale. If the airplane catches fire, and there is dirt nearby, I
will toss the extinguisher into the fire and make tracks in the dirt.

Rich S.

Portable Halon extinguishers made before 1995 are legal for use.
Aircraft are still allowed to use Halon.
It is illegal to release holon into the environment except for use in
"emergency" fires (ie it is illegal to use for "training" purposes)

wrote in message
...

Portable Halon extinguishers made before 1995 are legal for use.
Aircraft are still allowed to use Halon.
It is illegal to release holon into the environment except for use in
"emergency" fires (ie it is illegal to use for "training" purposes)

This, of course, varies with the country.

IMHO, Halon is not the ideal extinguishing agent for most aircraft fires,
especially in-flight. In order for Halon to be effective, it must be applied
to the fire before anything in the vicinity of the flammable gases becomes
heated to the ignition temperature of the gas, otherwise the fire will
re-ignite as soon as the concentration of the Halon drops below the
percentage needed to interfere with combustion.

Establishing and maintaining the required concentration of Halon is
difficult, if not impossible, in an open space. Even closed environments
such as sealed buildings are difficult to permeate. It is likely impossible
under an aircraft cowling when the plane is moving.

One needs to understand the process by which Halon inhibits fire. The fuel
(usually carbon-based material) has a greater affinity for the Halogens
(Chlorine, Fluorine, Bromine & Iodine) that it does for Oxygen. In the
presence of both Oxygen and a Halon, the fuel will "choose" to combine with
the Halon without the evolution of heat and light - what we call "Fire". If
sufficient Halon is available, all the fuel will combine with the Halon and
the fire will go out.

If the Halon is removed and there is still a source of ignition, the fire
will take up right where it left off.

If you've got a cabin fire, that's a horse of a different smell.

Rich S.

Rich S. wrote:

Establishing and maintaining the required concentration of Halon is
difficult, if not impossible, in an open space. Even closed environments
such as sealed buildings are difficult to permeate. It is likely impossible
under an aircraft cowling when the plane is moving.

I disagree. Have you ever used a Halon fire extinguisher? Back in the
Reagan era when the defense departement had a lot of money and Halon
hadn't yet been restriced, we were given training where we used large
Halon hand extinguishers to put out diesel fuel fires set in pans
outside.

If the Halon is removed and there is still a source of ignition, the fire
will take up right where it left off.

If you've got a cabin fire, that's a horse of a different smell.


With a flood system and a relatively closed space it takes a long
time for the Halon to disapate. Try lighting a lighter in a space
near where halon has been discharged.

Of course, much of what you said also applies to CO2. If the CO2
doesn't cool down the metal (which admittedly it has a higher
capacity to do than Halon), then you have the same (actually larger)
reignition problems.

the key statement is...

"It is likely impossible under an aircraft cowling when the plane is
moving. "

For this application it is a waste of weight, money, and time.

"Ron Natalie" wrote in message
m...
Rich S. wrote:

Establishing and maintaining the required concentration of Halon is
difficult, if not impossible, in an open space. Even closed environments
such as sealed buildings are difficult to permeate. It is likely
impossible under an aircraft cowling when the plane is moving.

I disagree. Have you ever used a Halon fire extinguisher? Back in the
Reagan era when the defense departement had a lot of money and Halon
hadn't yet been restriced, we were given training where we used large
Halon hand extinguishers to put out diesel fuel fires set in pans
outside.

If the Halon is removed and there is still a source of ignition, the fire
will take up right where it left off.

If you've got a cabin fire, that's a horse of a different smell.


With a flood system and a relatively closed space it takes a long
time for the Halon to disapate. Try lighting a lighter in a space
near where halon has been discharged.

Of course, much of what you said also applies to CO2. If the CO2 doesn't
cool down the metal (which admittedly it has a higher
capacity to do than Halon), then you have the same (actually larger)
reignition problems.

"Ron Natalie" wrote in message
m...
Have you ever used a Halon fire extinguisher?

Yup. I have fought actual aircraft fires using Halon, Dry Chemical (both
"Purple K" and "Super K"), Protein foam, CO2, etc., etc. For a picture, see
http://temp.corvetteforum.net/c4/elw...mp/oysters.jpg or
http://tinyurl.com/csndg . That's me in the middle next to the pilot's
seat. All those little black dots are fresh oysters he was bringing back
from Canada. The white stuff is Dry Chemical - 1,500 pounds of it. It
wouldn't stop the fire until we covered it with foam. Items like the burning
tires would reignite the gasoline behind us after we had moved the hose line
past. Had to replace my bunking outfit after that one - too many burn holes
to repair it.

With a flood system and a relatively closed space it takes a long
time for the Halon to disapate. Try lighting a lighter in a space
near where halon has been discharged.

I spent several years inspecting, discharging and signing off fixed Halon
system in computer rooms, satellite communications buildings, and one
180,000 sq. ft. building for Boeing that I can't even talk about. There are
no areas on a light aircraft which are sealed tightly enough to establish or
maintain a proper concentration of Halon. You can "overkill" a simple pan
fire with a portable extinguisher, but that won't work on an engine
compartment fire when you're in the cockpit.

Halon is a wonderful product, for it's purpose.

Of course, much of what you said also applies to CO2. If the CO2 doesn't
cool down the metal (which admittedly it has a higher
capacity to do than Halon), then you have the same (actually larger)
reignition problems.

Some other factors must be considered with CO2. Being heavier than air, it
tends to settle in a low spot - very important in ship fires. Halon diffuses
throughout the space. I'm not sure how the Latent Heat of Vaporization
compares between Halon and CO2. In either case the cooling capability is a
very minor effect when it comes to extinguishment. If you want cooling, use
water. If you want to secure the area and prevent reignition, use foam.

In a three-dimensional fire such as an aircraft fire, all bets are off. Even
foam may not prevent reignition. Trust me - it is scary to be wading in Jet
A trying to plug a leaking tank when the stream coming from the tank keeps
igniting. Even in a drill. 8-}

Rich S.

You say that you are required to carry an extinguisher. I assume that the
regulation specifies the minimum rating of the extinguisher - if not the
agent.

Haven't found the regulation pertaining to the quantity, though 2 lbs. seems
the norm. If anyone has the specific information, that would be appreciated.

"RV9" wrote in message
...

You say that you are required to carry an extinguisher. I assume that the
regulation specifies the minimum rating of the extinguisher - if not the
agent.

Haven't found the regulation pertaining to the quantity, though 2 lbs.
seems
the norm. If anyone has the specific information, that would be
appreciated.

The regs probably specify a numerical rating rather than a weight. In
addition to the number, there should be some letter(s) which rate the
extinguisher for the type of fire. A = Ordinary combustibles, B = Flammable
liquids, C = Suitability for fires involving electricity, D = Flammable
metals, etc. I must admit that I have been out of the fire business for
twenty years and much of my knowledge is out-of-date, especially where
regulations are concerned.

Here's an explanation of an extinguisher's rating taken from the NFPA
question and answer page:

I have a dry chemical fire extinguisher rated 2-A:10-B:C. What does that
rating mean?
Extinguishers achieve their ratings by putting out fires in laboratory
settings. The fire test standard is UL711, Standard for Rating and Fire
Testing of Fire Extinguishers. For the 2-A rating, 78 pieces of trade-sized
2-by-2-by-255/8 inch (5-by-5-by-66 centimeter) spruce or fir are placed in
a wood crib in 13 layers, then ignited and allowed to burn for 10 minutes.
Another fire test uses a vertical wood panel with 10-by-10-foot
(3-by-3-meter) furring strips. A third traditional fire test using excelsior
may be eliminated. The 10-B test involves a 25-square-foot
(2.3-square-meter) pan of heptane. The C rating doesn't involve fire, but
requires that the extinguishing agent not conduct electricity when
discharging across a 10-inch (25-centimeter) air gap between a grounded
plate and a potential of 100,000 volts AC. If the fires are extinguished
during the tests, the extinguisher gets the rating.

Rich S.

You can watch a bit and buy one from a Canadian seller.

When one comes up on ebay.