Effectiveness of Fire Retardant Coating on the Basis of LOI Analysis of Polymeric Materials: A Review

The growing use of polymers in construction, transportation, electronics, and consumer products has raised serious concerns about fire safety due to their high flammability and production of toxic gases during combustion. Flame retardant coatings offer a proven and efficient passive fire protection method. These coatings function by forming a thermal insulation barrier when exposed to heat or flame. They work through mechanisms such as intumescence (expanding and forming a protective char layer), endothermic decomposition (absorbing heat), release of non-flammable gases (like water vapor or ammonia), and drip suppression, thereby delaying ignition, reducing flame spread, lowering heat release, and minimizing smoke generation. Recent fire disasters such as the Grenfell Tower fire (UK, 2017), AMRI Hospital fire (Kolkata ,india,2011) and warehouse fires in Delhi (2022) and Beijing (2023) have emphasized the importance of applying flame retardant coatings on to polymeric materials used in public and industrial spaces to prevent rapid fire propagation .This paper includes the process of preparation of flame retardant intumescent coating using monoammonium phosphate, boric acid, paraffin liquid light, cation and anion exchange resins, fire suppression gel, xylene, silicon or acrylic binders, and calcium carbonate. Every material's role in improving flame resistance by studying the fire behavior of polymeric material .it is observed that The Limiting Oxygen Index (LOI) method, following ASTM D2863–19 can be used as the primary evaluation technique for proposing its effectiveness to flame retardancy of polymer.