Posted By Dave Wolfenden A question was posed to me yesterday concerning the use of powder fire extinguishers, in relation to the requirements of DSEA. Is there a risk of a dust explosion when attempting to extinguish a fire with a powder extinguisher? Would any risk be increased by using the extinguisher where incoming electrical mains transformers are, as our transformers are housed in seperate buildings that only have one wall that is completely open to atmosphere? (the transformers are 11Kv incoming and oil emmersed) The fire safety contractor who supplies the extinguishers has not had this posed to them before and has gone to seek information.

Posted By Geoff Burt Powder extinguishers causing an explosion??? Come on, think about it - what is the point of a powder fire extinguisher! Geoff

Posted By Gavin Gibson Is this the case of a little knowledge being a dangerous thing or should we consider mandating breathing apparatus before using carbon dioxide extinguishers?

Posted By Jane Blunt You can be certain that if a powder can be blown around by the wind, then so can the gas from a CO2 extinguisher. The distinction is that you can easily see what is happening with the powder. We had a Distribution Board go up in smoke one day - 3-phase, 400A per phase. Fortunately the doors to the Board were open, so that the equipment could be made dead quickly, and a powder extinguisher did an excellent job of putting out the fire. Jane

Posted By Ken Taylor No two fires will be identical and, obviously, you will need to have the correct extinguisher sited so as to be available when and where needed. We were always taught that, whilst dry powder can be used on electrical fires, the problem is that it will not effectively penetrate through tortuous routes into electrical equipment whereas CO2 delivered closely and under pressure will do so. This is why we see so many of them sited adjacent to electrical intake rooms, electrical plant, etc. When it comes to fires in the open air, the use of either can be difficult in windy or wet conditions or in untrained hands and I have certainly witnessed some comical and less than effective use of dry powder. I believe that the question here relates to an area open on one side to the elements. Can we agree that an informed risk assessment is called for taking into account all the circumstances and that this should determine the best extinguishant and means of delivery for the particular need?