1989

Pakkala, Liisa; Ryynänen, Tiia

The aim of the research project was to develop upholstered furniture with improved fire safety properties. The minimum requirement level was defined as the level where ignition was caused by smokers' materials. More severe ignition sources were the wood crib ignition sources BS 5 and BS 7 specified in BS 5852: Part 2. The effect of barrier interliners on the post-ignition properties of full-scale furniture was studied in an instrumented fire test room where the temperature, rate of heat release, heat flux, smoke production and toxic gases could be measured. The experiments proved that it is most important to choose compatible cover and filling materials. If the cover material ignites, it can become a very effective secondary ignition source which can cause a severe fire growth even in FR quality foam. Where more severe ignition sources are likely to occur, hardly any cover material alone will provide insulation effective enough to protect the filling foam. In such cases charforming insulation layers between the cover and the filling materials are needed. Polyurethane foam of a special quality, preoxidized carbon fabric and FR treated cotton fabrics proved to be the most effective fire barriers. By using FR quality filling materials the ignition threshold of upholstered furniture can be raised considerably. But if the effect of the ignition source exceeds the ignition resistance of the combination, the result may be uncontrollable burning even in FR polyurethane foam.