The necessity of fire extinguishers:
For the prevention and fighting of fire, you must have enough fire extinguishers of the correct types, along with other equipment, as identified in your fire risk assessment. The material that is being burned determines the classification of fires. The type of fire must be matched by the extinguisher.
Anybody who will be using fire fighting equipment must be familiar with its operation and basic firefighting techniques. It is important that the correct type of extinguisher be used to put out the fire.
The wrong extinguisher could have serious consequences. Electrocution can result from using a water extinguisher near an electrical source. Water spray and water mist extinguishers can be used on electrical equipment. The extinguisher’s body will bear the label “Approved for 35 kV dielectric testing” They have been tested to 35,000 Volts per meter. Water spray and water-mist extinguishers don’t conduct electricity through spray or mist, because there isn’t a continuous path, unlike a waterjet extinguisher.
Dry powder extinguishers and carbon dioxide (CO2) prevent oxygen from reaching the fire, but they don’t cool the burning material like water. If the powder is blown away, the fire can rekindle.
Foam extinguishers were originally designed to be used on Class B fires. However, they can also be effective on Class A fires since they are predominantly water-based. Many foam spray extinguishers also have dielectric test approval.
Use a fire extinguisher
People who are not trained in using fire extinguishers shouldn’t use them. You should ensure that someone has raised the alarm before you attempt to extinguish a fire using a fire extinguisher.
Use the right type of extinguisher to put out the fire. Then follow the four-step process called PASS.
- Pull: Pull the pin to interrupt the tamper seal.
- Aim: Point the nozzle or the hose towards the base of the fire with your aim. The CO2 extinguisher’s horn can get very cold, and it can cause skin damage.
- To release the extinguishing agent, squeeze the handle.
- Sweep: Move from side to side at base of fire, fuel source, until the fire is out.
Many people can put out small fires safely. A fire beyond your abilities can cause serious injury or death. Do not attempt to tackle a fire that is in its initial stages. Always ensure your safety and therefore the safety of others.
Fire extinguishers should be a standard safety item in every home or business. This guide will help you decide how many, how big, and which type of extinguisher you need. The guide will also cover the various types and classes of extinguishers as well as their uses.
Underwriters Laboratories, Inc. rates fire extinguishers according to what type of fires they can put out. There are three types of fires. Paper, wood, cloth, and rubber are all examples of Class A fires. Class B fires are those that involve flammable liquids such as gasoline, paint thinners, grease, oil, or solvents. Electrical fires are classified as Class C. Fire extinguishers rated B, C, or A is the best for home use.
Each fire extinguisher also has a numerical rating which indicates how large a fire it is capable of fighting. A 4-A rating, for example, means that the unit can put out twice as many Class A fires as a unit with an equivalent 2-A rating. C class (electrical fires) does not have numeric ratings. The C rating is simply an indication that the extinguishing agents in the unit are not electrically conductive.
Monthly check the dial gauge of your fire extinguisher. The gauge’s needle indicates whether the unit can be operated or needs to be recharged. You should have your unit recharged by a professional. These professionals are usually listed under Fire Extinguishers within your Yellow Pages. No matter how short the use, it is important to recharge your unit.
Fire Extinguisher Classes Ratings
On the label of a fire extinguisher, you should see the following symbols or letters. These symbols and letters indicate the type of fire extinguisher one should use. New fire extinguishers will have the larger symbols listed below, instead of the old style (a letter in an angled shape) that was shown beside each class name.
A fire classified as an “A” fire would have a fuel of paper, wood, or cloth. The majority of fires we see are classified as ‘A’ fires. Because they are the most common type of fire, most fire extinguishers can extinguish class ‘A fires. To extinguish a class ‘A’ fire, it can be either smothered (or drowned). If you have to extinguish a Class ‘A’ fire, look for the symbol on the left.
A ‘B’ fire is one that has been lit by liquid combustibles (not ordinary, electrical, or metallic), such as gasoline, kerosene, and propane. A class ‘B fire must be extinguished by either chemical or physical smothering. A class ‘B” fire should not be extinguished by water. It will often cause the liquid to splash and will not extinguish it. If you have to extinguish class ‘B” fires, look for the symbol on the extinguisher.
A ‘C’ fire is one that has been lit by electrical equipment, other than ordinary, liquid, or metal. Class ‘C’ fires must be put out. Never use water or any other liquids that could conduct electricity. If you are trying to extinguish a fire of class ‘C’, look for the symbol on the left.
Combustible metals such as magnesium and lithium can be used to light fires. If you have to extinguish a fire of class ‘D’, look for the symbol on the left.
This is a more recent classification of fire. Extinguishers of the class ‘K’ are designed to complement kitchen fire suppression systems. These extinguishers can be used to put out grease, cooking oil, and fat fires. If you are trying to extinguish a fire of class ‘K, look for the symbol to your left or the letter ‘K” symbol.
Multi-Class – Combinations of the Classes Above
There is no symbol available. What happens if the fuel in your fire is gasoline (class A), soaked rags(Class A), or live electricity (class C), igniting magnesium powder (class D). Multi-class fires can exist in many different situations. What fire extinguisher do you need? Do you need to keep five different extinguishers? It is possible, but not essential. Most extinguishers are capable of handling multiple types of fires. The majority of common extinguishers are capable of handling fires of A, B, and C classes. However, it is important to read the label before using it. The classes ‘D’, ‘K’, and ‘C’ are less common and will not be used together with other fire extinguisher types.
Types of fire extinguishers (extinguishing agents).
Fire extinguishers can use eight types of extinguishing agents. These include ABC Dry Chemical, BC Dry Chemical, Dry Powder, Water, Foam, Water, Foam, Halogenated, Carbon Dioxide, and Wet Chemical. Each of these agents can be applied to any of the fire classes listed above, as shown below.