Interesting fire extinguisher

lionel wrote:

If there were a cheap / portable extinguisher for lithium fires, I would put one in the plane.

For mobile phone batteries and the like, you can just carry a tinful of sand. I’m serious.

Peter wrote:

I can see a lithium battery catching fire as the most likely scenario

Alas, this system is not adequate for metal fires :-| neither are the halon extinguishers we carry for that matter. If there were a cheap / portable extinguisher for lithium fires, I would put one in the plane.

I would be concerned about a device which runs until exhausted, with no way to stop it.

Also can you imagine trying to put a fire out during flight? I can see a lithium battery catching fire as the most likely scenario, and then you want another approach (a battery bag, for example).

It would make sense to have some of these in the engine compartment instead, but I wonder how well they work in an area with a high airflow. They are however used around jet engines, but perhaps there isn’t much airflow around there. Whereas in piston GA the entire compartment has a lot of airflow – except behind the engine.

Reading a bit on the Internet, it seems what makes one’s voice squeaky when inhaling Helium (or hydrogen) is their low density; being less dense than air. According to https://pubchem.ncbi.nlm.nih.gov/compound/Bromotrifluoromethane#section=Vapor-Density, Halon 1301 (Bromotrifluoromethane) is approx 4 to 5 more dense than air.

More reading suggests it is not only the density that determines the voice squeakiness, but the speed of sound in that gas, which would be affected not only by density (in an ideal gas, that is proportional to molecular weight if I recall correctly), but also by the heath capacity, making the prediction of whether Halon 1301 makes one’s voice squeaky more difficult to make.

On the more important subject, Wikipedia gives a lethal dose of 834000ppm (that is 83,4%!!!) for Halon 1301, which seems to support that it doesn’t actively deplete the oxygen, merely displaces it. (Note the “immediately dangerous” concentration is far lower at 40000ppm, that is 4%.)

@Maoraigh, you’ve confused halon with helium. Halons as such are non-toxic, alhouth they do present two potential hazards: firstly, halon vapours are significantly heavier than air, so there is a danger of suffocation in pits, shafts, etc.; secondly, when exposed to fire, halons can form small quantities of corrosively toxic (as distinct from systemically toxic) compounds. Nevertheless, neither of the two should be a big issue in aircraft fire. Incidentally, the aerosols produced by the system in question would not be very problematic, either. In both cases, a significant danger would be mostly present in enclosed spaces, such as submarine compartments and the like.

Maoraigh wrote:

Does halon suffocate?

That was very much emphasised in the PPL courses, then in the instructor ground courses here. My understanding, gotten from there, was that it actively depletes the oxygen from the air, my understanding was that it would chemically capture it. Looking now around on the Internet, I get more the impression that Halon 1301 is more of an inert gas that “just” displaces the air, and thus makes an air-poor, and thus oxygen-poor, atmosphere.

Maoraigh wrote:

I thought it just made your voice squeekie.

The gas known to me for its “squeaky voice” feature is Helium.

Does halon suffocate? I thought it just made your voice squeekie.
This system has killed. The fine particles would affect lungs.
A co-owner put a small dry powder extinguisher in a bag in our Bolkow Junior. I removed it before flying. The Bolkow cockpit
has no openable in flight door. The possibility of it going of if the bag moved in turbulence scared me. It could only be used on the ground.

Stickandrudderman wrote:

Perhaps you just toss it at the fire but then the chances of it coming to rest exactly where you want it to are pretty slim.

According to Wikipedia, there are other models that are meant to be tossed in the fire; they discharge in all directions (360°), while this one is one-direction (low angle) jet.

For what it is worth, “Element” is the rebranding by the USA importer of the Italian manufacturer FSS Fire Supression Systems ESP; their list of distributors is at http://www.fss-esp.com/distributors.html; it is called “Fire Stryker” in Oceania and some parts of Africa and “Fire Safety Stick” in the UK.

Maoraigh wrote:

I wonder how useful it would be in a light aircraft.

Well, compared to the Halon systems we have onboard… my hope was that we would be less likely to suffocate ourselves from the suppression of the oxygen?