Halon 1211 & 1301 are some of the safest fire extinguishants known and the most effective in putting out fires. They would not be listed by all nationally recognized laboratories such as UL, ULC, FM if they weren’t. They have been used for over 25 years for safeguarding valuables, chemicals, computer rooms etc because of their low toxicity.
They have had wide application up to 1995, when their production was ceased due to the Montreal Protocol by-laws. They are now exclusively used for the Military and Aviation Industries…primarily because of their unique qualities, low toxicity and superb fire fighting capabilities.
Because of their exceptional extinguishing powers, the fires are thus extinguished much faster than when using other chemicals such as dry chemical or C02 , thus resulting in considerable low overall toxicity. This is because the toxicity of the combustion fumes cause much more harm, i.e. much more toxic than the Halon itself. The fumes for example from plastics & synthetics burning are very toxic & dangerous when inhaled. Thus any extinguishant that puts out the fire faster is advantageous for reducing toxicity. It is practically impossible to inhale a sufficiently high concentration of Halons(2-5% in air) for a few minutes to temporarily harm an individual..if using a fire extinguisher or automatic Halon unit. Most automatic units are used in enclosed areas where individuals are normally absent. Even so, back in the 80’s & 90’s, computer rooms were protected by flooding the whole room with Halons, and at times people were present when the system was discharged. This never resulted in harming someone. In fact, there has been hardly anyone harmed directly from Halon ingestion reported.
To show the perfect safeness of Halons, Dupont back in the 80’s had a video showing a person in a telephone booth filled with 5% Halon 1301 in air, not being able to light his cigarette lighter!!