Fire represents one of the biggest workplace safety threats. It is not just a hazard for the employees but for nearby buildings and the public as well. It can result in serious injuries and even fatalities. Workplace fires can cause extensive property damage and can either destroy the entire worksite or render it out of service indefinitely, causing loss of jobs and subsequent loss of income.
Fire can and does start at any time, and it is therefore critical that we are prepared and equipped to deal with a fire should the need arise. Being unprepared will result in a disaster and most probably lead to fatalities. Being prepared to deal with a fire involves having staff trained in firefighting, having evacuation plans in place, practising evacuation drills at least twice a year, doing regular inspections in the workplace identifying fire hazards, doing fire risk assessments, having fire extinguishers and firehose reels in good working condition and much more.
Fire extinguishers are portable devices enabling us to quickly and effectively deal with small fires. Fire extinguishers are crucial pieces of equipment, but they do have their limitations, which are very important for us to know as well as how to use them and which type to use on the different types of fires.
Classes of Fire
The different classes of fires we can encounter in the workplace are:
Class “A “fires consist of flammable solids like wood, paper, material, plastic etc.
Class “B” fires consist of flammable liquids like petrol, paraffin, oil, diesel etc.
Class “C” fires consist of energized electrical fires, like computers, servers, air conditioners etc.
Class “D” fires consist of flammable metals like magnesium, aluminium, sodium etc. Class “K” fires are kitchen fires involving cooking oil, animal fat, grease etc.
Types of Fire Extinguishers and Their Uses
Now let’s have a look at the different types of fire extinguishers and their uses:
1. Dry chemical fire extinguishers
Probably the most widely used fire extinguishers in the workplace as they are very effective on Class “A”, Class “B” and Class “C” fires. They will have very little effect on Class “D” fires as these fires require a special type of powder.
2. Carbon dioxide (CO2) fire extinguishers
These can be used on Class “A” fires and are very effective for Class “C” fires. They will have little effect on any Class “B” fires as they do not form a layer over the liquid.
3. Water fire extinguishers
Can only be used on Class “A” fires and should never be used on Class “B”, Class “C” fires or Class “D” fires.
4. Foam fire extinguishers
They are effective on Class “A” fires and excellent for Class “B” fires but should never be used for Class “C” fires or Class “D” fires.
Water and foam extinguishers should never be used on a Class “C” fire as water conducts electricity and can lead to the operator being electrocuted. Using water or foam extinguishers on a Class “D” fire will cause an explosion, injuring the operator and causing faster fire spread.
5. Fire Blankets
For Class “K” fires a fire blanket is usually very effective. There is a new fire extinguisher available specifically for Class “K” fires. (Called a Class “K” fire extinguisher.) It will disperse a liquid in a low-pressure mist form, cooling down the flames as it travels through them and forming an emulsion-type layer as soon as it contacts the oil. This layer will prevent oxygen from getting to the oil, extinguishing the fire quickly and effectively.
Using the wrong fire extinguisher can lead to injuries or worse and can cause the fire to spread faster. Unfortunately, fire extinguishers have a lot of limitations as they only contain a limited amount of product and are designed to deal with small fires, so they are ineffective on bigger fast-spreading fires. They require a special technique to use them effectively so the person using the fire extinguisher needs to be properly trained in its use.
All fire extinguisher types need to be serviced annually by a competent technician and we should check our different types of fire extinguishers monthly to ensure they stay in optimal working condition.
Few people realize how fast a fire spreads through a building. A fire that can be easily extinguished with a fire extinguisher can turn into an unstoppable inferno in as little as ten seconds, leading to disaster. Having the correct and sufficient fire extinguishers available with the location shown by a fire extinguisher sign, together with well-trained and confident office firefighters, will probably save the day or at least buy enough time for all staff to safely evacuate the building.