Low-cost wool-based fire blocking inter-liners for upholstered furniture

New Zealand is reluctant to implement mandatory fire safety regulations for domestic furniture because of the cost/benefit even though up to 30% of household deaths and injuries over the past 20 or more years can be attributed to soft furnishings. Work has been carried out to develop a low-cost inter-liner using fire retardant treated wool with altered proportions of different fire resistant synthetic fibres that may be attractive for voluntary inclusion by manufacturers. Bench- and full-scale tests have been conducted to characterise the fire performance of composites of polypropylene upholstery fabric, different inter-liner materials and a polyurethane foam core. Inter-liner blends that reduced the peak rate of heat release, extended the time to peak rate of heat release and reduced other combustion product output were identified. A blend of 75% Zirpro treated fire retardant wool and 25% Panox fibre was found to be the best candidate material when fire performance, cost and practical application were considered.