Part III: Firefighting

Fire and the dangers of fire

Most fires are the result of human error or technical faults. Fire is usually caused by:

  • Faults in machinery and technical problems
  • Actions by unqualified persons
  • Activities with a high fire-risk
  • Combustion in bulk or waste products
  • Arson
  • Carelessness when smoking

1. Fire and the fire triangle

Fires that need to be extinguished can be defined as:

  • Unwanted
  • A source of damage or danger
  • Likely to spread out of control

You can detect a fire in several ways:

  • See flames or smoke
  • Hear flames crackling
  • Feel heat
  • Smell burning

A fire requires three things:

  • A combustible material
  • Sufficient oxygen
  • A sufficiently high temperature

This is called the fire triangle. If these three factors are present in the right proportion, a fire will occur. 

If we remove one of the three factors the fire will go out. Extinguishing a fire therefore amounts to removing at least one side of the fire triangle:

  • Removing the combustible material: often difficult. For gas fires, however, it is simple and in fact the only way to extinguish the fire. Just shut off the gas supply. 
  • Removing the oxygen: it is possible by smothering a fire. 
  • Lowering the temperature: spraying the fire with an extinguishing agent will lower the temperature.

EROs are trained to extinguish fires in their early stages. 

2. Dangers in the case of fire

There is one golden rule for EROs: put your own safety first!

Dangers of smoke:

  • Smoke develops and spread more quickly than the flames
  • Biggest danger from smoke is inhaling it and burning the bronchial tubes
  • Most victims of fire die from smoke and from the fire itself
  • Smoke is always toxic and life-threatening 
  • EROs should not go into areas where there is smoke!

Dangers of heat:

  • Fire always leads to a rise in temperature
  • Temperature can build up at the top of the room or building
  • The heat can fall like a blanket and can burn anyone who is present 
  • Can also cause material and people to catch fire

Dangers of carbon monoxide:

  • Carbon monoxide is always released during a fire
  • Cannot be seen, smell or taste
  • Can lead to asphyxiation after a short time

Dangers of electricity cupboards:

  • Found in every organisation, the place where the power supply enters the building, but are not necessarily meter cupboards
  • Danger with fire and electricity cupboard is that there might still be electricity present
  • If possible switch the electricity off before starting to extinguish the fire
  • Never us water to extinguish a fire in an electricity cupboard, because water conducts electricity
  • Use a CO2 extinguisher for a fire in an electricity cupboard
    • If that is not possible use foam
    • If that is not possible use powder
  • Always alert the fire service if there is a fire in an electricity cupboard

Old and new pictograms for hazardous substance labels

3. Different kinds of fire

Before you extinguish a fire, you need to know what is on fire so that you can choose the right type of extinguishing agent. Extinguishing agents work by removing one or more sides of the fire triangle.

Fires are divided into the following classes from A to F:

  • Class A fires: solid combustibles (wood, paper, textiles)
  • Class B fires: liquids and substances that become liquid at higher temperature (diesel oil, benzene, turpentine, fuel oil, candles)
  • Class C fires: gases (natural gas, LPG, butane) 
    • Mix well with oxygen and often results in fierce fires
    • A danger of explosion with gas fires
  • Class D fires: metals (aluminium, light alloy car wheels, sodium)
  • Class F fires: fats and oils (cooking oil, deep-frying fat)

On portable extinguishers there are pictograms (A | D) that tell for what kind of fire the extinguisher can be used.