The Types and Placement of Fire Extinguishers
Friday, January 4, 2013
A fire is a nightmare that few of us wish to contemplate before it occurs, but advance planning is precisely what can save us from its worst consequences. Fire extinguishers are widely available and should be used.
There are five types of fire extinguishers that are distinguished by the type of fire that they put out. It is important to understand the differences, since using an extinguisher on the wrong fire can accelerate the fire and thus be very dangerous.
- A fire that involves ordinary combustibles like wood, paper and cloth is typically labeled A. Label B is the label for a flammable liquid fire that involves paraffin, gasoline, oil or paint; Label C for electrical equipment; Label D for metals like aluminium, magnesium, titanium. These labels are usually on the side of the fire extinguisher.
- The most common fire extinguisher is the Air Pressurized Water extinguisher used on type A fires. If used on other fires, it will either spread them or cause explosions. They operate by cooling the fire.
- Dry chemical fire extinguishers come in two types: BC extinguishers contain sodium bicarbonate or potassium bicarbonate and put out B and C fires, and ABC extinguishers contain monoammonium phosphate and put out A, B and C fires. They are very messy to use indoors and might damage electrical equipment, so this should always be kept in mind. These extinguishers deprive the fire of oxygen and thus smother it.
- CO2 carbon dioxide fire extinguishers are those used on B and C labeled fires. Since they are less messy than the dry chemical variety, they are often preferred for fires that are indoors are involve electrical equipment, but the advantage of the dry chemical type is that they leave a non-flammable substance on the extinguished material that reduces the Chance of re-ignition.
- Foam Fire Extinguishers are used on class A and B fires, and are safer than water if accidentally sprayed on electrical equipment, though still undesirable.
- Class D fires are put out by specialist extinguishers that contain chemicals that target specific metals.
- All extinguishers should be examined once a month and repaired or re-filled as needed.
Recommended placement for fire extinguishers:
- They should be mounted on brackets or in wall cabinets. The carrying handle should be between one and one-and-a-half metres above the floor. The larger the unit, the lower it should be placed so that shorter and less strong individuals can lift it.
- In public spaces like schools, office buildings or factories, there should be at least one extinguisher per 50 metres space.
- All homes should have at least one fire extinguisher that should be placed as close to the kitchen as possible.
- In large restaurant kitchens, an extinguisher should never be more than ten metres away.
Once we understand fires and the extinguishers designed to put them out, we regularly maintain them and we have placed the extinguisher correctly, we are armed to combat the next fire to the best of our ability.