On board fire extinguisher halon

[Dave0549jv]

Re: On board fire extinguisher halon

If the halon system is designed and sized correctly, when discharged into the intended area it will reduce the available O2 so the combustion cannot be maintained but enough oxygen will still remain to support human life for the duration of the discharge and latent period before the halon dissipates. When I worked with new Halon installations (years ago, but not on boats) we actually had to demonstrate a extinguishing event by discharging the system and recording the available O2 in the discharge area. If the O2 level was too high OR too low, the system had to be modified or the amount of halon discharged increased or decreased.

That's actually pretty interesting. Do you think that boat manufacturers had to be held to the same standards? I wonder if they had to go through the same level of 02 testing for each engine compartment to be fitted with Halon. Also, I heard that once Halon reaches a high enough temperature, it actually becomes poisonous, but I'm assuming that's an old admiral's tale.

 

[Outsider]

Re: On board fire extinguisher halon

Don't know about other makes, but I know Albemarle used HALON systems for decades without having an engine space anyone could fit in. The smaller FireBoy systems had (have) a 'charged' indicator light, but if it's not illuminated, you still have to find out if it's the indicator or the canister. Since a great many vessels (dare I say 'most') don't have an engine room, per se, the greatest danger from HALON came from residual gas settling into occupied spaces. HALON systems used to be inspected by weighing, removed my canister after I purchased the boat and the gage was frozen 'in the green', the canister empty. The correct weight should be on the canister label ...