Fire protection of electric cables by coating

Fire retardant intumescent coatings based on phosphates, amides, polyols, amino and acrylic hinders but free from asbestos and halogenated compounds, have been developed for polyvinyl chloride (PVC) insulated power cables. The fire performance of the coatings has been assessed by employing different procedures as per relevant national and international standards. The cable specimens, with these coatings, did not show any surface spread of flame on exposure to fire. However, the coating swelled to form a spongy, cellular insulating foam, which acted as an effective barrier against the conduction of heat to the surface and to the core of the cable specimen. The coatings were found to be quite effective in reducing the burning behavior of power cables. Significant improvement in circuit failure time is noted in coated cable specimens.