Basic fire fighting and prevention.
The fire, fire classes and the right extinguishing agent
Introduction
Most large fires start as small fires that could have been extinguished. Elementary fire fighting is about being able to act quickly and correctly in the first seconds — but always with your own safety in mind. You should never put your own life at risk to extinguish a fire.
Fire triangle
A fire needs three things at the same time: combustible material, oxygen and an ignition source (heat). This is called the fire triangle. Remove just one of the three elements and the fire goes out. Extinguishing works precisely by removing one of the elements — e.g. smothering the oxygen with a blanket or cooling and removing the heat with water.
Fire classes
Fires are divided into classes according to what is burning. The class determines which extinguishing agent you can use — a wrong choice can make the fire worse or be directly dangerous.
| Class | Typically burns in |
|---|---|
| A | Fixed materials like wood, paper, and textiles. |
| B | Fluids such as petrol, oil and paint |
| C | Gases |
| D | Metals |
| F | Fat and oil in kitchen (deep fryers) |
Selection of extinguishing agent
- 01Fire blanket: suffocates small fires e.g. in a pot or clothing — place it carefully over and cut off the oxygen
- 02Water: good for class A (wood, paper, textiles), but never on electricity or fat
- 03Powder extinguisher: broadly applicable but creates considerable mess and reduced visibility
- 04Carbon dioxide extinguisher (CO2): suitable for electrical equipment, removes oxygen
- 05Always follow the marking on the extinguisher for which classes it can be used for
Evacuation and prevention
If the fire cannot be extinguished quickly and safely, you must alarm, evacuate and close doors after you to limit smoke and fire. Smoke is life-threatening — stay low where the air is best. Prevention is about keeping escape routes clear, knowing the location of extinguishing equipment and fire alarms and avoiding overloading electrical installations.
What the law requires
A workplace must have suitable fire-fighting equipment (BEK nr. 607/2026 § 12, stk. 1). The employer must arrange fire-fighting and evacuation and appoint people who are «adequately trained» («fornødent oplært»). There must be «a sufficient number» of them (BEK nr. 609/2026 § 22). If there is a particular risk of fire or explosion, there must be emergency, evacuation and drill plans.
Hot work
Welding, cutting and other work with open flame or heat require a hot work certificate. The certificate is valid for 5 years. The course lasts at least 1 day with practical extinguishing, and an online course does not give you the certificate. The certificate is valid in Denmark and Norway. In Sweden it is not valid for certificates issued after 1 July 2023, and in Finland not for certificates issued after 31 December 2025.
Tall buildings
The chart shows which types of buildings in Denmark have at least 8 storeys. Think about how long the way out is from the top floor, and why escape routes must be kept clear.
“If you don't extinguish the fire within a short time, close the door, leave and lock up — and let the emergency services handle the rest.”
— Fire safety basic rule