New regulations for hazardous air pollutants drove operations to compliant coatings. Powder coatings were the most popular choice. A screening of intumescent powder coatings was carried out comprising binders like thermoplastics as plasticised polyvinylchloride and polypropylene as well as non-cross linked thermosets as polyurethanes. Intumescence was achieved by addition of the intumescent ingredient bicyclopentaerythritol phosphate, by the intumescent combination polyethylene glycol as binder with ammonium polyphosphate and binders comprising intumescent phosphororganic polyesters. The intumescent ingredients and components were characterized by thermogravimetric analysis and described by chemical formulas together with their balances of weights and heats of formation. The electrically loaded powders were sprayed on grounded steel panels and subdued a fire test. The time, until the coated panels reached 500℃, was observed. The panels coated with the plasticised polyvinylchloride plus bicyclopentaerythritol phosphate and those protected by the polyurethane comprising polyethylene glycol and ammonium polyphosphate delayed the period of time, until 500℃ were reached, significantly and were equal in efficiency with the reference, the commercial water borne intumescent varnish.
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