There are 4 main types of fire extinguisher in general use, plus dedicated
extinguishers for specialist applications such as cooking fats & oils and
metal fires. The 'old' British Standard for fire extinguishers (BS 5423)
stipulated that the entire body of the extinguisher be colour coded to
indicate the contents as follows:
Red-Water, Cream-Foam, Blue-Powder and Black-CO2.
BS EN 3 requires that ALL
fire extinguishers should be coloured RED,
although BS 7863 allows between 3% to 5% of the body (usually the label)
to be colour coded in accordance with the 'old' system.
CLASSES OF FIRE
Class A Fires involving solid materials such
as wood, paper or textiles.
Class B Fires involving flammable liquids
such as petrol, diesel or oils.
Class C Fires involving
Class D Fires involving
Class *E Fires involving live electrical
Class F Fires involving cooking oils such as
in deep-fat fryers.
*According to British Standard 5306 there is no class 'E',
however for simplicity and ease of understanding for the layman, we call it
class E for convenience.
Water extinguishers (red label) -
For use on Class A fires.
The user can direct water onto a fire from a
considerable distance however 9-litre water extinguishers are quite heavy, approx
15kg. Some water extinguishers with additives can achieve the same A rating
whilst being much smaller and lighter. Whilst water 'jet'
extinguishers are not suitable for use on live electrical equipment, water
spray fire extinguishers often carry a 35kV dielectric test approval. The
reason water spray can be used on live electrics is that there is no
continuous 'stream', water spray has air gaps between the droplets which
breaks the continuity. Water spray
extinguishers are rapidly gaining in popularity over the usual '6L foam and
2kg CO2' combination.
The A rating is the test rating of an extinguisher on a
'standard' test fire. The test measures how much of the test crib fire it
will extinguish, in the case of a 9L water extinguisher, this is usually
1.3m. For calculation purposes the decimal place is dropped, and the
extinguisher is rated at 13A. The A rating of the extinguisher is used to
calculate the number of extinguishers needed in a building. This figure is
based on an old assumption that a 2 gallon (9L) water extinguisher would
provide cover for 200 sq m of area. The number of A rated extinguishers
necessary for an average commercial building is calculated as follows:
1. First calculate the floor area in sq m
2. Multiply this by 0.065 (this gives the 'A' rating
for the area concerned)
3. Divide the area A rating by the A rating of the
4. Round up to the nearest whole number.
e.g. For a floor area of 2100 sq m, and with 21A
2100x.065 = 136.5
136.5/21 = 6.5
Round up to 7
Answer: Seven 21A extinguishers required.
Water extinguishers with additives (red
label) - Suitable for Class A
fires, and can also be used on Class B fires and where appropriate (this
will be indicated on the extinguisher). These are usually more efficient
than conventional water extinguishers.
Foam extinguishers (cream label) -
Can be used on Class A or B fires and
particularly suited to extinguishing liquid fires such as petrol and diesel.
They should not be used on free-flowing liquid fires without advanced
training as this type of fire has the potential to
rapidly to adjacent material. This type of
extinguisher is not suitable for deep-fat fryers or chip pans.
Powder extinguishers (blue label) -
be used on most classes of fire and achieve a good ‘knock down’. They can
also be used on fires involving electrical equipment but will almost
certainly render that equipment useless. Because they do not cool the fire
appreciably it can re-ignite. Powder extinguishers can create a loss of
visibility and may affect people who have breathing problems, and are not
generally suitable for enclosed spaces and are therefore not recommended for
use inside buildings unless there is absolutely no alternative.
Carbon dioxide extinguishers (black label) -
suitable for fires involving electrical equipment as they will extinguish a
fire without causing damage (except in the case of some electronic equipment
e.g. computers). As with all fires involving electrical equipment, the power
should be switched off if possible.
Class ‘F’ extinguishers -
suitable for commercial catering establishments with deep-fat fryers.
Fire blankets -
should be located in the vicinity of the fire
hazard they are to be used on, but in a position that can be safely
accessed in the event of a fire. Fire blankets are suitable for dealing with
small fires in containers of cooking oils or fats and fires involving
the use of wet tea towels was advocated if a fire blanket was not available,
however fire & rescue service advice is now NOT to use these as many
injuries have been occurring.
Commissioning and installation
BS 5306-6 recommends that fire extinguishers are
commissioned and installed by a competent person.
Fire Extinguisher Commissioning
FIRE EXTINGUISHER SALES
companies charge extortionate prices for fire extinguishers (£200 - £300).
You can buy fire extinguishers at very
reasonable prices on-line from the following web site:
should be serviced by a competent person at least annually.
We can provide fire extinguisher servicing at
competitive prices in most areas. Email us for a quote on
firstname.lastname@example.org we need to know where you are
and how many extinguishers you have.
FIRE EXTINGUISHER TRAINING
The Regulatory Reform (Fire Safety)
Order 2005, requires that the responsible person must, where necessary 'take
measures for firefighting in the premises' and 'nominate
competent persons to implement those measures and ensure their training and
the equipment available to them are adequate......' It is important
that anyone expected to tackle a fire
should be trained, the implications if anyone is injured. and has not been
trained are obvious. Marsden Fire Safety
can provide such
TRAINING VIDEOS CD's
and DVD's are also available - click here
Have you seen the new
EVACUATION TRAINING AID - The
WHAT NOW ??? - Brilliant, simple and
providing tremendous benefit during evacuation drills and exercises.