When fire strikes, the potential for damage to people and property is tremendously high. The burning process requires four (4) elements ? often referred to as a fire tetrahedron:
- Fuel - Common fuels include coal, natural gas, wood, paper, etc.
- Oxygen - The air we breathe is composed of
between 20% and 21% oxygen, which is
sufficient to sustain most fires.
- Heat - In order to start a fire, heat must be supplied to initiate the chemical reaction. This is normally in the form of a spark or small flame, but could be high temperature.
- Sustaining chemical reaction - This is called combustion and involves the transformation of the fuel and oxygen into water and carbon dioxide. By-products include heat and light. The heat sustains the reaction.
If we remove any of the above four items, the fire will stop. For example, if something is burning in a pot, put a lid on the pot, oxygen will be cut off and the burning will stop.
There are five main types of fire:
- Class A - Ordinary Combustibles
- Wood, paper, cloth
- Ordinary trash
- Class B - Flammable Liquids and Gases
- Class C - Fires involving electrical equipment - these could be any of the other type of fires, but electrical equipment is involved
- Class D fires - Combustible Metals and Metal Alloys (not very common)
- Class K fires - Fires involving cooking materials
- Cooking Oils
- Animal and vegetable fats
A multi-purpose dry chemical fire extinguisher labeled ABC is good for extinguishing class A, B and C fires, and is recommended for home use. Sand is good to stop metal fires.
In your school and your workplace you may find one or more of the following fire control systems:
Fire sprinklers - these will be activated automatically in case of fire in the room.
Standpipe and hose system - these are generally located in the hallway. In case of fire they should be used only by trained persons. If you start the fire alarm, the fire department will respond as soon as possible.
Portable fire extinguishers - these can be used to stop small fires if you are trained to use one. Use the fire extinguisher if you know how to use it. Otherwise, follow the evacuation procedure. There is no time to try to figure out how to use a fire extinguisher.
The classroom may be equipped with safety features and equipment such as:
Fire exits - Doors with illuminated exit signs serve
as an exit route from the classroom in case of fire alarm.
Fire alarm - Usually located near fire exits. If you notice a fire, activate the alarm as you are leaving the room.
Fire extinguishers - Usually mounted on the wall near exits. Use a fire extinguisher only if you have received "hands-on" training.
Smoke detector (also called a smoke alarm) - Smoke in a room
will start an alarm. If the detector rings its' alarm, follow the fire protection
rules of your school or workplace or leave your house
Extinguishers should be located on each floor or level. You should have one in the kitchen (not too close to the stove), another in your workshop, and in the garage, basement, camper and at the cottage. A unit for the car is also advisable. Locate the extinguisher just inside the door to the area concerned. You can reach it easily and fight the fire, while remaining close to the escape route.
Check the extinguisher pressure gauge every month to ensure the unit is holding its charge. If you use the extinguisher, no matter how much agent has been used the extinguisher should be considered empty, and you should have it refilled as soon as possible. The extinguisher will not maintain its pressure once it has been operated.
The decision to fight a fire at your home is critical. Regardless of your choice, always get your family out of the house first, and call the fire department.
If you feel that you can extinguish the fire with your fire extinguisher, do so with caution and use the following steps.
- Check that the pressure indicator is full, and after pulling the pin, a very short burst with the extinguisher as a check to make sure it works - if it does not work, leave immediately.
- Approach the fire with caution, and make sure there is a clear path to an exit behind you.
- Leave immediately if the fire is still burning after using one full extinguisher - it is likely the fire is too large for you to fight.
Using a Fire Extinguisher
Smoke alarms should be installed between each sleeping area and the remainder of the building. Where a sleeping area is served by a hallway, install the alarm in the hall. Always install the smoke alarm on or near the ceiling and follow the manufacturer's installation instructions.
Test your smoke alarm every month using the alarm test button. Install a new battery at least once or twice a year. If the low battery warning beeps, replace the battery immediately.
To clean battery-powered smoke alarms, vacuum the inside using the soft bristle brush. Vacuum as you would the battery powered unit. Restore power and test the unit when finished. Replace any alarm which is more than ten years old with a new smoke alarm.