Fire can be easily produced if there are 3 key elements in place: oxygen, fuel (or combustible material), and heat (or ignition source).

   Once a fire has started, it can be put out by removing one of the elements from above. It is called “breaking the fire triangle. Either element relies on others to keep the fire going.

   The heat generated by the fire is extremely dangerous, but the most harmful outcome of the fire for the alive beings is making the air unbreathable. Fire consumes most of the oxygen in order to continue burning with immense velocity. For example, the oxygen from a normal room can be spent in only 30 seconds. The smoke adds to the lack of oxygen making those who breathe it suffocates.

   The most common way to put a fire out is by using a fire extinguisher, but you cannot use the same type of extinguisher for every fire. That is because not all the combustible materials react the same for the extinguisher composition.

   In order to know which fire extinguisher must be used, a person must be trained and qualified to know all the procedures for which and how to use a specific fire extinguisher.

   Based on the combustible materials, fires can be separated into classes:

   Class A. Carbonaceous materials, such as paper, cloth, wood, or rubber. This class is usually referred to as “solid fuel fire”. For this class, a water extinguisher should be used in order to contain the spread of the fire and eliminate it.

   Class B. Flammable liquids or liquefiable solids, such as petrol, oil, paint or adhesive. This class of fire can be fought by using a foam extinguisher or if the fire is flowing, a dry-powder extinguisher should be used at the front edge of the fire in order to separate the flames from the fuel.

   Class C. Flammable and liquified gases. This class is especially a very dangerous one because it can turn into an explosion if not an action against it in the critical required time. Class C fires are best dealt with by the use of dry powder extinguishers.

   Class D. Combustible metals such as magnesium, sodium, phosphorus, and similar ones can be only dealt with by trained firefighters. For these kinds f fires, special chemical extinguishers can be used and if another type of extinguishers are used, such as water, it can cause more damage than good. As a last resource, dry sand or earth can be used to smooth the fire until a suitable extinguisher is available.

   Class F. Cooking oils or fats are most known for their auto-ignition capacity and high temperatures. Due to the extreme heath that these fires can produce, using an incorrect extinguisher can be extremely dangerous. Wet chemical, dry chemical, or foam-based extinguishers are the most effective, but the surface of the fire must be sealed immediately because Class F fires can re-ignite.

   Electrical fires usually enter in the “other types of fire” category. Usually, the electrical equipment and service connections have a designated space, with fire-rated doors in which only competent personnel can enter if they have a permit. These fires can only be dealt with using CO2 or dry powder extinguishers. The use or incorrect fire extinguishers can produce further damages and put at risk the safety of others. So, DO NOT TRY TO FIGHT A FIRE IF YOU ARE NOT TRAINED TO DO SO!

   For a construction site to be legally safe, a fire emergency system and procedures must be put in place before commencing the work. Also, all the operatives and visitors entering the site must be made aware of the measures taken to protect their health and safety in case of a fire.