FIREPROOF MEDIA. Fire retardants used in wood, also called fireproof or anti-fire, should meet the following requirements: obstruct ignition, prevent the fire from spreading, delay the chemical transformation of the wood structure. Wood is protected against the destructive effects of fire by saturating its surface with a solution of the selected fire retardant, with the appropriate concentration. There are a number of ways to use fire retardants, namely: lubrication and spraying, dipping wood in a flame retardant solution, impregnation of wood under pressure, finally osmosis, that is, lubricating wet wood with a paste prepared by mixing fire retardant with glue. In addition to the fireproof specifics found on the market, and produced by patented methods („Ogniofix”, „Flamort” in inside), A number of different chemical compounds have fire-retardant properties: Those are: Magnesium chloride, , copper sulfate, water glass, sodium phosphate, zinc chloride, zinc chloride, borax, finally zinc and alum sulphate, as having no other use in construction.