Extinguishers Flashcards
4 main types
Water
Foam
Dry powder
Co²
Colours of the 4
Water signal red
Foam pale cream
Power French blue
Co² black
What class can use water on
Class A
Solids (wood, paper, furnishing)
Class to use on foam on
A + B
Solids and flammable liquids
Class to use dry powder on
A B C D
Solids, flammable liquids, gases, metals
Class to use co² on
B C D
Flammable liquids, gases, metals
Class A
Solids
Wood, paper, coal, textiles, furnishings
Class B
Flammable liquids
Oils, diesel, wax, grease, sprirts, oil based paints
Class C
Gases
Natural gases, hydrogen, camping gases, propane, butane, methane
Class D
Metals
Aluminum, magnesium, potasium
Class F
Cooking oils and fats
Properties of water
6-9 litres
Capacity over 5 litres should last 60 secs
Jet of 7m spray 4 m
10 bar pressure
Should discharge 95%
Length of hose 80%of body
Advantages and disadvantage of water
Advantages
Cools and extinguishers sold fuel fires quickly
Can be used as jet or spray
Disadvantages
Not to be used on electrical fires
Not to be used on cooking fats
Properties of foam
6- 9 litres
5 litres should last 30 seconds
10bar pressure
95% discharge
Self aspiration or non aspirating
Advantages and disadvanges of foam
Advantages
Cools and smoothers fires
Can be used on flammable liquids
Disadvantage
Not to be used on chip pan fires
Foam blanket could break away and re ignite BURNBACK
Properties of dry powder
1-12kg in size
Discharge 85%
Powder treated with a flow additive (anti caking)
Different powders for different fires
Should shake every do often to break up
Advantages and disadvantages of powder
Advantages
Can be used on class A b c
Safe to use on electrical fires
Disadvantages
Does not cool
Messy in operation
Winf and moisture will effect
Visibility reduced
Properties of Co²
Staves fuel of oxygen
Range from 0.9 to 6.8kg
56 bar pressure
Expansion rate 450:1
Specially shaped horn
Discharge 95%
-79 degrees on metal pipe
Advantages and disadvantaged Co²
Advantages
Can be used on electrical fired
No permananted residue left
Good at penetrative enclosed spaces
Disadvantages
Little cooling capability
Noisy
Heavy
Needs to be sent away for refil
What does water do
Removes heat
By cooling the surface it stops pyrolysis
What does Co² do
Removes oxygen
Starvation of oxygen to the fire
What does foam do
Removes heat and oxygen
Small amount of cooling
Starvation of oxygen to fire
What does powder do
Removes oxygen
Smothers the fuel, it interups the chain of combustion
