Hi 

can dry powder extinguishers be used indoors or has this recently changed so they can only be used outdoors?

thanks

Dry power is no longer recommended by 5306 - 8 for indoor use as the powder will obscure vision, affect breathing and is very damaging to surfaces and equipment

Powder is still very useful and it's not an absolute no-no indoors if justified by a Health & Safety assessment. However for your usual place of assembly, office, shop, hotel, healthcare premises, etc it's not appropriate - it's usually industrial type risks where the need for it's rapid knockdown properties outweighs the secondary damage and health risks where it can remain.

Depending on the risk to be covered then Wet Chemical, Water Mist, Triclass, Foam, Water Spray are all possibles as powder extinguishers can be found covering all sorts of risks!

Thanks AB.

No problem, saves me typing it out again!

The environment, occupancy/persons at risk and fire risks all are part of the factors to consider - most places I deal with they are removed/not installed, but there are exceptions.

Powder is often installed in general commercial premises for Class C (gas) risks, overlooking completely the fact that tackling a class C fire other than by simply shutting off the gas supply is a specialist and potentially hazardous job and that the staff in these premises are not trained or equipped to do so (all 'general' fire safety training including extinguisher courses trains staff not to extinguish a gas jet fire) - the BS acknowledges this and so boiler rooms and gas intakes etc don't really need powder at all...

In my experience powder extinguishers are commonly found in plant rooms but in a recent visit to a Local Authority care home Scottish Fire & Rescue recommended that the powder extinguisher in the boiler room be replaced for the reason Tom referred to in his previous post.