Fire protection in buildings - Introduction to Fire Safety Management - page 224

Table 9.13 Summary of the types and uses of portable fi re fi ghting extinguishers

Extinguisher/ medium Best for Danger How it works

Water Panel colour Wood, cloth, paper, plastics, Do not use on burning fat Mainly by cooling burning material.

coal, etc. Fires involving or oil or on electrical

solids appliances

Dry powder Panel Liquids such as grease, fats, Safe on live electrical Knocks down fl ames and

colour oil, paint, petrol, etc. but not equipment, does not smothers the fi re.

on chip or fat pan fi res . penetrate the spaces in

equipment easily and the

fi re may reignite. Does not

cool the fi re very well and

care should be taken that

the fi re does not reignite

Aqueous fi lm forming Wood, cloth, paper, plastics, Do not use on fl ammable Forms a fi re extinguishing fi lm on

foam (AFFF) Panel coal, etc. oil fi res the surface of a burning liquid. Has

colour Fires involving solids a cooling action with a wider

extinguishing application than water

Liquids such as grease, fats, on solid combustible materials.

oil, paint, petrol, etc. but not

on chip or fat pan fi res .

Wet chemical Panel Cooking oils and fats These extinguishers are The wet chemical agent reacts with

colour generally not recommended the burning oil or fat to form a

for home use 'suds-like' blanket across the fuel

surface. This 'suds-like' blanket

extinguishes the fi re by excluding

the air, and by preventing the

release of fl ammable vapours.

Carbon dioxide CO 2 Liquids such as grease, fats, Do not use on chip or fat. Vaporising liquid gas which

Panel colour oil paint, petrol, etc. but not This type of extinguisher smothers the fl ames by displacing

on chip or fat pan fi res . does not cool the fi re very oxygen in the air.

well and you need to watch

that the fi re does not start

up again

Fumes from CO 2

extinguishers can be harmful

if used in confi ned spaces:

ventilate the area as soon as

the fi re has been controlled

Fire blanket Fires involving both solids If the blanket does not Smothers the fi re.

and liquids. Particularly good completely cover the fi re, it

for small fi res in clothing and will not be able to extinguish

for chip and fat pan fi res the fi re

provided the blanket

completely covers the fi re .