FPASA BULLETIN FP 03
PORTABLE FIRE EXTINGUISHERS – TRAINING AND USE
The action taken to control a fire during the first few minutes following its discovery determines whether it will be contained and extinguished or spread.
It is therefore in the interests of any employer to ensure that all employees are adequately trained in the use of portable fire extinguishers.
The level of training, however, would vary according to the responsibilities of employees within a fire defence system.
Training
The training of employees in the use of extinguishers should be both theoretical and practical in nature in order to be effective. Theoretical instruction is vital since staff should be instructed in the suitability of extinguishing media on various types of fires and in fire extinction theory, but this cannot substitute for practical training sessions. Only by using extinguishers on fires will employees be able to appreciate how the burning characteristics of fires can change, the radiated heat which can be expected from various fires and the size of fire which could safely be dealt with when using an extinguisher.
Theoretical instruction
Theoretical instruction promotes the understanding of fires and extinguishers and can be used to introduce employees to the basics of the chemistry of fire, methods of extinguishment, classification of fires and the methods of operating various extinguishers. Any symbols, printed information or colour coding which may appear on the extinguishers could also be explained.
Practical instructions
Using extinguishers on fires not only ensures that employees operate them correctly but teaches the correct techniques of applying the extinguishing medium to various types of fire.
Batches of extinguishers should be used on a rotation basis during training sessions for the following reasons:
- All extinguishers on the premises will be tested in this way to ensure that they function properly.
- Wear and tear through over-usage of a few extinguishers will be avoided.
- All extinguishers need to be pressure-tested from time to time and since they have to be emptied first, periodic pressure testing could follow a practical training session.
General
•If possible ensure that back-up assistance is available before tackling a fire and preferably work in pairs.
•Ensure that an escape route is available before committing yourself to tackling the fire.
•Follow the instructions on the extinguisher label when activating the unit. Depending on the type of extinguisher being used, break the seal then remove the safety device (a pin or safety clip) or turn the wheel valve on the cartridge fully open and check the operation of the unit by briefly activating the control mechanism before approaching the fire.
•Do not place yourself at risk. If the fire is too big or begins to spread, vacate the area immediately.
•Apply the extinguisher medium to the base of the flames and moving the nozzle with a rapid side to side action, drive the flames away from you. Fore vertical fires start at the base of the flames and move upwards. (The application technique for foam extinguishers is explained elsewhere in this bulletin).
•If the fire is out of doors approach the fire from the windward side.
•When approaching the fire adopt a crouching attitude which provides some protection against heat and smoke.
•Never tilt or invert any extinguisher during operation unless it is a turn-over type.
•Keep alert for any changes in the fire pattern.
•When tackling a fire involving electrical equipment, isolate the power as soon as possible to prevent re-ignition.
•When extinguishing a flammable liquid spillage fire never walk in the spillage area in case the flames flash back.
•When tackling flammable liquid fires using a controllable discharge type extinguisher, do not interrupt the flow of extinguishing medium until the fire is completely extinguished.
•Ensure that the fire has been completely extinguished and that no sparks remain.
•When the fire has been extinguished, back off slowly and never turn your back on it.
While the general rules for operating fire extinguishers apply in most cases, the following specific instructions should be noted for various extinguisher types.
Water-type extinguishers
The approximate effective range of a 9 unit is 4 m to 7 m. The controllable discharge type conserves water and once the flames have been subdued the operator can interrupt the water flow and open up the burning combustible materials using a rake or spade. This will expose smouldering areas which can then by systematically extinguished. When using non-controllable units water discharge continues and helpers should assist the operator in opening up burning materials
Foam extinguishers
The approximate effective range is 4 m to 5 m. Direct the foam jet at the far inside edge of the flammable liquid container. This allows the foam to build up and flow across the surface of the liquid. Where this is not possible, the operator should stand well back and allow the foam to gently fall onto the liquid surface. Direct discharge of the foam into the burning liquid should be avoided.
Dry powder extinguishers
The approximate effective range of a 9 kg unit is 4 m to 5 m. The powder cloud tends to interfere with the chemical reactions inside a flame thereby achieving extinguishment, so the operator should stand back initially to allow the powder stream to fan out.
Thereafter move in closer using a rapid side to side action with the nozzle. Care should be taken not to direct the powder jet into the burning liquid as this would splash the liquid out of the container and spread the fire.
For fires involving electrical equipment, try to get the powder to penetrate motor casings, switchboards, etc.
For gas fires direct the powder into the flame from behind the gas leak. The gas supply should be immediately cut off to avoid a gas build up. The use of an extinguisher on a gas flame should only be considered as a last resort.
Carbon dioxide extinguishers
A 6,8 kg unit will have an approximate effective range of up to 3 m. CO2 is most effective when used close up to the fire. Ensure that the gas penetrates casings of electric motors or switchboards, etc. Windy conditions will detrimentally affect the medium’s extinguishing capability. The discharge horn should always be held by the insulated handle only and not by the horn itself, since the low temperatures generated by discharge can cause cold burns to the skin.
Published by
Fire Protection Association of Southern Africa
(Incorporated Association not for Gain)
(Reg. No. 73/00022/08)
P O Box 15467, Impala Park, 1472