Originally Posted by Djarraluda
For anyone with FM200, sadly the effects of it's use on a fire are the production of toxic by-products. Be very careful if one has gone-off in an engine
compartment. Commercially, we vent the space before opening the door. Also commercially, we are removing FM200 to replace with an inert gas (IG55 being one of the best).
Hum, Inert gas displacement
suppression systems such as the argon/nitrogen mix in IG55 will do the job. Like FM200 and the Old 1301 halon all are safe when properly designed. However as is the case with many systems, most are somewhat oversized to allow for gas leakage. A slightly oversized IG55 system is not any safer the a fm200 or 1301 system. Vessel engine
spaces are not aire tight due to the nature of the beast.
All CFC and HFC's produce highly toxic byproduces when they come in contact with flame. That is the case with fm200 and with halon 1301. However FM200 and the old Halon 1301 were quite effective in stopping the combustion process very very quickly. That is prior to decomposition in flame. A undersized system would be more of a danger
While the production of halon 1301 Like R12 and R22 and other hfc'S were banned by the Montreal protocol that does not mean that existing halon 1301 or fm200 suppression systems need to be removed. Many telephone switch centers still use 1301 and FM200 (large systems).
Myself were I to find a 1301 or Fm200 system aboard, I would leave it be, if the bottle looks to be in good condition with no corrosion
on the tank or valve. Odds are the 1301 and FM200 bottles are leak free. It's fairly rare for one to leak.
Edit: I should clarify. The typical dry power extinguishers will compact and may not function if too old and not serviced. Servicing being to tap around the cylinder loosening the power. (I actually do that with mine) 1301 and fm200 are a liquid under pressure and do not have that issue. As most small systems have a simple fusable link there is little to go wrong. If you have a electric
activated system, what fails is wire and the detectors. The tank is fairly bullet proof