- Author
- Levin, B. C. | Paabo, M. | Braun, E. | Harris, R. H., Jr.
- Title
- New Approach for Reducing the Toxicity of the Combustion Products From Flexible Polyurethane Foam.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Book or Conf
- Business Communications Co., Inc. (BCC). Recent Advances in Flame Retardancy of Polymeric Materials: Materials, Applications, Industry Developments, Markets. Annual Conference, 2nd. May 14-16, 1991, Stamford, CT, 1-6 p., 1991
- Keywords
- polyurethane foams | flexible foams | toxicity | combustion products | copper | hydrogen cyanide | experiments | flammability | thermal decomposition | inhalation toxicity
- Abstract
- Hydrogen cyanide (HCN) is one of the gases which is produced during the thermal decomposition of flexible polyurethane foams and which (in combination with carbon monoxide and other fire gases) contributes to the toxicity of the smoke. Flexible polyurethane foams treated with copper or various copper compounds produced significantly less HCN when thermally decomposed than the identical but untreated control foams. The effect was observed with copper levels as low as 0.1% by weight. The decreased atmospheric concentrations of HCN resulted in the reduction of the acute inhalation toxicity (as measured by lethality in Fischer 344 rats) produced from exposure to this smoke. This reduction of HCN and toxicity occurred regardless of whether the copper or copper compound was added to the foam during its formulation (prior to the foaming process) or as a post-treatment (after formulation). In all these reported experiments, the foams were thermally decomposed under small-scale laboratory conditions in the cup furnace smoke toxicity method apparatus via a two phase procedure previously shown to produce high concentrations of HCN. The addition of 0.1% by weight of cuprous oxide (the most efficient of the tested copper compounds) did not affect the flammability characteristics of the foam, e.g., ignitability, heat release rate, smoke obscuration, rate of flame spread, heat of combustion, or CO/CO2 ratios.