The study also says that the retardants make no difference to the prevention of fire in buildings where a fire-safe thermal barrier already exists.
Such a change would bring the US building codes in line with regulations in Sweden and Norway.
The research team, which is drawn from US-based centres including the University of California and the Lawrence Berkeley National Laboratory, conducted a review of fire safety literature since the mid-1970s and concluded that the addition of halogenated organic compounds to plastic insulation materials such as polystyrene, polyisocyanurate and polyurethane is costly, ineffective and environmentally damaging. Their conclusions are published in the latest issue of the journal Building Research & Information.
The team, which was led by fire expert Dr Vytenis Babrauskas of Fire Science & Technology, investigated the impact of the Steiner Tunnel test. This is used to test the propagation of fire over the surface of all sorts of building materials in the early stages of fire, before flashover point is reached.
Their paper suggests that changing the US building codes to exempt foam plastic insulation materials from the test would avoid the use of thousands of tonnes of flame retardants that are known or suspected to be persistent organic pollutants.
“Such a change would … decrease the cost of foam plastic insulation and encourage the use of insulation materials for increasing building energy efficiency and mitigating climate change,” they conclude. “The potential for health and ecological harm from the use of flame retardant chemicals would be reduced and the fire safety of buildings would be maintained.”