Important: never mix powders - only extinguishers containing the same type of powder should be used at the same time.

Safe on live electrical equipment, although does not penetrate the spaces in equipment easily and the fire may re-ignite.

This type of extinguisher does not cool the fire very well and care should be taken that the fire does not flare up again.

Smoldering material in deep seated fires such as upholstery or bedding can cause the fire to start up again.

Do not use on domestic chip or fat pan fires.

Point the jet or discharge horn at the base of the flames and, with a rapid sweeping motion, drive the fire towards the far edge until all the flames are out.

If the extinguisher has a shut-off control wait until the air clears and if you can still see the flames, attack the fire again.

Similarly to almost all extinguishing agents the powders acts as a thermal ballast making the flames too cool for the chemical reactions to continue.

Some powders also provide a minor chemical inhibition, although this effect is relatively weak. These powders thus provide rapid knockdown of flame fronts, but may not keep the fire suppressed.