An extinguisher used in time stops a small fire. A wrongly chosen or wrongly used one, however, can make things worse. This lesson says which extinguishers exist, what they are for and how to handle them.
Who may fight a fire
Under § 18 of the Fire Protection Act, everyone must put a fire out if possible, or at least stop it spreading. Nobody expects you to risk your health, though. Fight only a small fire, only when you can see an escape route, and after the fire has been reported. If you cannot control the fire within moments, leave.
Types of extinguisher
Extinguishers differ in their extinguishing agent. You can tell the type from the label and the pictograms on the extinguisher, which show the classes of fire it is intended for (A, B, C, D, F) and, where relevant, a symbol showing whether it is suitable for live equipment.
- Powder. A universal ABC agent. It suits classes A, B and C and can also be used on live equipment (as the label says). Drawbacks: it raises dust, the dust damages electronics, and it is unsuitable for loose bulk materials. It is hard to breathe in the powder, so ventilate.
- Snow (CO₂). Carbon dioxide extinguishes by smothering. It suits mainly class B and electrical equipment and electronics, because it evaporates after use and leaves nothing behind. It does not suit smouldering materials. In a small room it can displace oxygen, so ventilate the room after fighting the fire. CO₂ gas is very cold, so do not touch the horn with a bare hand.
- Water. It extinguishes by cooling. Suitable only for class A (wood, paper, textiles). Do not use it on flammable liquids, oil, fat or live equipment.
- Foam. Foam extinguishes by cooling and by separating the fuel from the air. It suits classes A and B. It contains water, so it is not for live equipment unless the label says otherwise.
- For class F. In kitchens with deep fryers, an extinguisher with an agent made for fats and oils (marked F) is used. Ordinary water would throw the fat about.
- For class D. Flammable metals are extinguished with special powder agents marked D. Water would cause a violent reaction.
The employer chooses extinguishers according to the flammable materials at the workplace (Decree No. 246/2001 Sb., § 3). The most suitable extinguisher is the one nearby.
How to use a portable extinguisher
- Choose an extinguisher that suits what is burning. Check the label.
- Release the safety pin: pull out the pin.
- Stand at the distance the extinguisher allows and with the wind behind you, so the flames and smoke do not burn you.
- Aim the nozzle at the base of the flames, not at the top.
- Squeeze the lever. Sweep the agent over the ground from side to side. With a burning liquid, do not direct the jet straight into it, or you will splash it.
- Expect the extinguisher to empty quickly, depending on its size within a few seconds to tens of seconds. So do not waste the agent, and start from a suitable distance.
- Do not turn your back on the fire until you are sure it is out. It can reignite.
- Report the use of the extinguisher to the employer, so that it is checked and refilled.
If several extinguishers are nearby, several people can use them at once. Do not fight the fire alone unless you have to.
Checking extinguishers
You are not the one who checks them, but you should care whether they are in order. Under Decree No. 246/2001 Sb. (§ 9):
- the operability check is done after each use, when in doubt and at least once a year,
- the extinguisher has a seal and an inspection label with the date of the last check,
- the periodic test (pressure test, internal inspection) is done every 3 years for water and foam extinguishers and every 5 years for the others,
- extinguishers must be withdrawn when they are faulty or older than 20 years (CO₂ after 40 years).
If you see an extinguisher with no seal, an expired label or damage, report it.
Hydrants
A wall hydrant is a device with a water supply and a hose that can be unrolled to fight a fire. You find it in the corridors of some buildings, in a marked cabinet. Call for help first. A hydrant is meant for fighting fire with water, so the same limits apply as for water extinguishers: do not use it on live electrical equipment or on burning oil and fat. When using it, follow the instructions on the cabinet. Do not block hydrants or the area around them.
Other equipment: a fire blanket (smothers small fires, for example in a kitchen, or clothing on a person) and sand.
Summary
- Fight only a small fire, only with a clear escape route and after reporting it.
- Powder is universal (ABC), CO₂ suits electrical equipment and class B, water and foam extinguish mainly class A.
- Do not use water on oil, fat or live equipment.
- When fighting a fire: release the pin, aim at the base of the flames, squeeze, stand with the wind behind you and never turn your back on the fire.
- Extinguishers are checked at least once a year. Report faulty or unchecked ones.