Non-flammable additive changes the properties of flammable coating. Flame retardant is the ability to sustain the fire. Overall, burning is defined as a chemical process of rapid oxidation combined with loss of a large amounts of heat and mass. Flame retardants (also called non-flammable), or restricting burning retardants are called - inhibitors of combustion. They are supposed to delay combustion, and in the best case extinguish the fire.