Fire retardant coatings are intended for thermal insulation while protecting metal and other surfaces in order to increase their fire resistance in case of fire. They have a relatively small thickness, which increases significantly under fire conditions at high temperature influences. Fire retardant coating needs three main components. Carbon donor - pentaerythritol, polyalcohols, starch to form a carbonated protective layer. The inorganic acid for dehydration of the carbon donor is (poly) metaphosphoric acid (HO3P) n, which will form when ammonium polyphosphate (Novaflam APP) decomposes at a temperature of 275 ° C. A blowing agent, such as melamine, which releases gas (N2) necessary for the formation of foam.