Loss of Production
When fires are burning, no work can be done in that area of the mine. Loss of production results. Some fires are very difficult to put out. An area of the mine may have to be sealed up and no one will be able to work there until the fire is put out. This could take months. When there has been a fire in a workplace, it takes a long time to rebuild that area so that it can be worked again. All of these factors add up to the loss of income for the mine.
Legal Requirements:
Training and Use
The action taken to control fire during the first few minutes following its discovery determines whether it will be contained or whether it will spread.
It is therefore in the interests of any institution 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.
Fire team
At least one fire team per shift should receive intensive in-house training to ensure that team members are fully conversant with all the fire equipment available on the premises. This training should be on going and be extended to include the attendance of practical training courses run by independent organizations.
Department fire teams
Two employees should receive intensive training in the use of the fire extinguishers in the department in which they work. They would then be in a position to mount an initial attack on the fire whilst the fire team is assembling, thereby saving valuable seconds.
Security personnel
Members of the security department are constantly on patrol and often on duty when all other employees have vacated the premises, it is vital therefore that they receive intensive training in the use of extinguishers. Their training should be at least on the same level as that for department fire teams.
Employees
Large companies might find that it would be impractical to allow each employee to discharge fire extinguishers during training sessions. However, elementary theoretical instruction should at least be given, and employees could attend fire team training sessions to observe extinguishers in use.
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 all 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 that can be expected from various fires and the size of fire that 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 color-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, moving the nozzle with a rapid side-to-side action; drive the flames away from you. For vertical fires start at the base of the flames and move upwards.
If the fire is out of doors approach the fire from the windward side.
When approaching the fire adopt a crouching attitude that provides some protection against heat and smoke.
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 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.
Whilst 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 Lt Unit is 4m to 7m. 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 that can then be systematically extinguished. When using non-controllable unit’s water discharge continues and helpers should assist the operator in opening up burning materials.
Foam extinguishers
The approximate effective range is 4m to 5m. 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 l unit is 4m to 5m. 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 be considered as a last resort.
Halon 1211 (BCF) extinguishers
A 7-kg unit will have an approximate effective range of up to 4m. The medium is emitted in a semi vapour / liquid form with the liquid vaporising on contact with the flames forming a dense inert heavier-than-air cloud which smothers the fire. The vapour also interferes with the chemical reaction inside the flames thereby accelerating flame extinguishments.
Avoid using the medium in confined spaces indoors, as the decomposition products can be toxic and irritating. Windy conditions out of doors can have a detrimental effect on the medium’s extinguishing capability.
Carbon dioxide extinguishers
A 6.8-kg unit will have an approximate effective range of up to 3m. CO2 is most effective when used up to the fire. Ensure that the gas penetrates casings of electric motors or switchboards, etc. Windy conditions will detrimentally affect the medium 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.
