Extinguishers

Question 1

What are the classes of fire?

Answer 1

Class A Ordinary combustibles (e.g. paper, material, timber)
Class B Flammable liquids (e.g. petrol, oil, paint)
Class C Flammable gases
Class D Combustible metals (e.g. magnesium, titanium)
Class F Cooking oils and fats

Question 2

List specs for a Water Extinguisher

Answer 2

Colour. Red
Construction : welded stainless steel cylinder
Contents : 9 Litres water, pressurised with Air or inert gas to approximately 700kPa.
Used for : Class A Fires
Discharge time : 60 seconds up to 6M
Extinguishes by: Cooling (removing heat) and steam caused a slight smothering effect ( removing oxygen)

Question 3

List specs for Foam Extinguisher?

Answer 3

Colour: Solid blue or red with blue band
Contents : Approximately 8.4 litres of water plus 0.6 litres of foam concentrate (mixed at 6% ARF).
Used for: Class A, B and F (limited) fires.
Pressurised with: Air or inert gas to approximately 700kPa.
Discharge time : 45 seconds (maximum).
Five (5) metres (may be affected by wind).
Extinguishes by : Smothering (removing oxygen) and cooling
(removing heat).

Question 4

List the specs on a Dry Chem Extinguisher?

Answer 4

Colour: Red with white band.
Construction: Welded stainless steel cylinder
Contents: 4.5/9 litres of:
mono ammonium phosphate (ABE)
Used for: Class A, B, C and E fires
Pressurised with: Air or inert gas to approximately 1350 kPa.
Discharge time: 10-20 Secs
Distance/Throw: 3 to 4 metres.
Extinquishes by: works on the
chemical chain reaction

Question 5

List the specs on CO2 Extinguisher?

Answer 5

Colour: Red with black band.
Construction: Drawn steel cylinder.
Contents: CO in liquid form,
No pressure gauge due to gas being stored under pressure
Used for: Class B and E fires (and very small Class A fires).
Discharge time: 15 seconds approximately).
Distance/Throw: 1-2 M
Extinguishes by: Smothering (remove oxygen), negligible cooling.
Vapour density: 1:5
Expansion ratio: 450:1
Safety Valve: