Extinguishing a Fire
How to extinguish a fire and what dangers should you be aware of
In the previous section we talked about the fire triangle and its implications, in this section we will talk about how to use that knowledge to extinguish a fire and the other important considerations if you are going to attempt it.
RACE
RACE is an acronym used to assist you in decision making in the event of a fire, the first step is to stay calm and assess the situation, then:
Rescue any people in immediate danger, if safe to do so.
Alarm. Raise the alarm by alerting other people and calling 000
Contain. If practical and safe to do so, close all doors and windows.
Extinguish the fire using appropriate equipment, if safe to do so.
Even in facilities installed with an Automatic Fire Alarm (AFA) it is important to call ‘000’ so that the fire brigade can immediately respond more resources if required.
Extinguishing a fire
Before any fire fighting can take place there is an important safety step that must be undertaken, that is sizing up the fire. When determining how to fight a fire, or whether to attempt to extinguish the fire at all, you must consider these factors:
Size of the fire
Some fires may be too large to effectively extinguish with the resources available to you. For example if an entire meeting room or kitchen is on fire it is unreasonable to expect the average individual to be able to meaningfully extinguish the fire with one extinguisher.
The type of fuel that is involved
The type of fuel that is burning will affect the types of extinguishing agent that can be used. You would not, as an example, use water if the fire was cooking oil or a flammable liquid. The class of fire that is occurring will dictate what can and cannot be used to attempt to extinguish it.
Nearby Hazards
If the fire involves closed containers of flammable liquids or gas cylinders it may be too dangerous to approach to the range needed to effectively fight the fire with the resources available. This is only an example and your own decision making ability will be required when determining if the nearby hazards are too dangerous to attempt extinguishing.
Hazardous fire products
Is the smoke, heat or gases being produced by the fire a hazard to you? If you are unable to approach the fire from a position where you are protected from these fire products it may be too dangerous to attempt extinguishing. For this reason all fire extinguishers should, at least initially, be used from their maximum range. Things such as wind direction or the slope of the ground (in the case of a liquid fire) should be taken into account.
Escape route
Regardless of the effectiveness of your size up things can still go wrong. For this reason you must always have an escape route available. If any position that allowed you to avoid other hazards also prevented you having an available escape route, extinguishing should not be attempted.
Operating a fire extinguisher (PASS)
The acronym PASS is used as a memory device to help with the operation of a fire extinguisher. It lists, in order, the actions you need to take to use one effectively.
Pull the pin and test the fire extinguisher by squeezing the handle. This will give you the confidence that the extinguisher works and allow you to judge how far the extinguishing agent will travel from the nozzle. Remember to stay calm, if you squeeze the handle while trying to pull the pin it will jam up and be impossible to remove until you relax your grip.
Aim the fire extinguisher at the base of the fire. Aiming the fire extinguisher at the base of the fire allows the agent to be applied to the burning material directly. Remember, the flames themselves are not the source of the fire, aim it at the base.
Squeeze the handle to release the agent.
Sweep the nozzle side to side to spread the agent over the entirety of the burning material.
How fire kills
The majority of deaths in a fire are not caused by burns (although burns are still a major danger posed by fires), but by smoke inhalation. Often smoke incapacitates so quickly that people are overcome and can’t make it to an otherwise accessible exit. The synthetic materials commonplace in today’s environments produce especially dangerous substances. As a fire grows inside a building it will often consume most of the available oxygen, slowing the burning process. This “incomplete combustion” results in toxic gases.
Smoke is made of components that can be lethal in their own way:
Particles
Unburned, partially burned and completely burned substances can be so small they penetrate the respiratory system’s protective filters, lodging in the lungs. Some are actively toxic while others are irritating to the eyes and digestive system.
Vapours
Foglike droplets of liquid can poison if inhaled or absorbed through the skin.
Toxic gases
The most common, carbon monoxide (CO), can be deadly even in small quantities as it replaces oxygen in the bloodstream. Hydrogen cyanide results from the burning of plastics, such as PVC pipe, and interferes with cellular respiration. Phosgene is formed when household products, such as vinyl materials, are burned. At low levels phosgene can cause itchy eyes and a sore throat, at higher levels it can cause pulmonary edema and death.
Reduced oxygen levels
In addition to producing smoke, fire can incapacitate or kill by reducing oxygen levels, either by consuming the oxygen or displacing it with other gases. Heat is also a respiratory hazard, as superheated gases burn the respiratory tract. When the air is hot enough a single breath can kill.
Fire Prevention
The most effective method of keeping your premises fire safe is to not need to extinguish a fire in the first place. To work towards this goal you need to take proactive steps to minimise the opportunities fire has to take hold. Some general tips you might consider for this are:
Make sure hot work gets completed in a designated area free of combustibles
Maintain good housekeeping habits to prevent the build up of fuel
Making sure electrical equipment is tested and in good working order
Storing flammable or dangerous goods in designated, bunded areas
Having your staff educated in fire risks and behaviour