How not to use an extinguisher

When I teach practical fire extinguisher use I always start with a safety briefing which includes a diagram of the training exercise and the fact that you really do not need to get close to a fire to fight it - in fact getting too close can not only make the fire bigger it can also lead to the fire fighter being burned.

A standard dry powder extinguisher uses Nitrogen as a propellant gas as it is easily available (around 79% of the air you breath is Nitrogen), it is also inert. A typical working pressure for a dry powder extinguisher is around 190psi (appx 13 bar) and is capable of throwing the powder somewhere between 3 - 6 metres. Start from somewhere around the 4-5 metre mark and use a quick discharge of around 2 seconds, then re-assess as the powder will make it hard to see. If it safe and necessary you can move closer and repeat.

A Carbon Dioxide (CO2) has a much higher working pressure of around 800psi (appx 55bar) and getting too close to a liquid fire when using one will literally spread the liquid and fire as the video in this blog shows and turn a relatively small fire into a disaster within a few seconds.

Remember - the only fire extinguisher in common use that we fully deploy in one go is the wet chemical, all others we sweep, let go, re-assess.

Video used under fair use for educational purposes.