Nowadays, a large part of the multi-store buildings, sporting, storage, production and all kinds of premises are designed and constructed on the basis of metal structures, consisting of numerous and different types of beams and columns of structural steel.
Ensuring maximum protection of buildings in the event of fire is regulated by the European design and construction norms, and is a major stage of input materials selection. Although steel profiles are non-combustible, they also need to be protected as they lose their strength and load capacity when exposed to high temperature. In case of fire, steel elements can reach a critical temperature of 500°C just within 5 minutes. As at this temperature, profiles lose their bearing capacity and therefore, cause catastrophic consequences and collapses.
In such circumstances, the main concern is associated with the protection of profiles from overheating within a certain time interval required to evacuate the building, according to its purpose and internal layout.
There are different methods for Passive fire protection (PFP) of steel structures. As one of the basic methods is the laying of special coatings reacting at high temperature and providing the necessary steel insulation from aggressively rising external temperature. A required thickness of the specific coating is applied in advance, depending on the type of profile and the time required for fire protection, which, at high temperature, increases its volume several times and thus serves as a barrier between the fire and the steel. The flame retardant coatings provide, in combination with suitable primers and finishing coatings, an anti-corrosion protection, a long lasting life, and an aesthetic appearance of the buildings.