Experimental Evaluation of Flammability Parameters of Polymeric Materials
An evaluation of the fire behavior of polymers and liquids over a wide range of experimental conditions is made using a laboratory scale flammability apparatus developed by the author. Results are presented for the following fuel parameters: (1) minimum heat flux (surface temperature), energy, and critical mass loss rate required for the piloted ignition of fuel vapor-air mixture and kinetic parameter for fuel vapors; (2) “effective” heat of gasification of the fuel; (3) flame-convective and flame-radiative heat flux to the fuel surface; (4) mass generation rates of CO, CO2, gaseous hydrocarbons, and “pyrolyzate”,† expressed as fractional theoretical stoichiometric yields (or fractions of carbon in the fuel converted to the products); (5) chemical formula of the fuels based on measured elemental compositions; (6) heat release rates (actual, convective, and radiative) expressed as combustion efficiency of the fuel vapors and convective and radiative fractions of the theoretical stoichiometric heat release rate for the complete combustion of the fuel vapors; (7) net heat of complete combustion and actual heat of combustion of the fuels; and (8) the ratio of optical density per unit path length to mass concentration of the fuel vapors defined as “modified mass absorbency index.”
The apparatus and concepts used for obtaining the fuel parameters are also described.
The parameters are obtained for fuels about 0.008 m2 in area exposed to various values of external heat flux and mass fraction of environmental oxygen.
- 1.Aliphatic- Type Fuels
Liquids: methanol, acetone, heptane.
Granular: cellulose, polyoxymethylene, polyethylene, polypropylene, polymethylmethacrylate, nylon.
- 2.Aromatic- Type Fuels
Liquids: aniline, benzene, styrene.
Granular: polystyrene, styrene-butadiene.
Foams: polystyrene†, polyurethanes†, polyisocyanurates†, phenolic.
Chlorinated- Type Fuels. Chlorinated polyethylenes, polyvinyl chloride.
Results for composite fuels are also reported.
This report is based on work which was started in July 1975 and completed in November 1978 under Products Research Committee Grant No. RP-75-1-33A.
KeywordsHeat Release Rate Polyurethane Foam Mass Loss Rate Fire Retardant Fire Hazard
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- 1.H.S. Carslaw and J.C. Jaeger, Conduction of Heat in Solids, 2nd ed., Chap. II, p. 75, Oxford University Press, London (1959).Google Scholar
- 2.D.J. Rasbash, Relevance of fire point theory to the assessment of fire behavior of combustible materials, in International Symposium on Fire Safety of Combustible Materials, p. 169, University of Edinburgh, Center for Industrial Consultancy and Liaison, Edinburgh (1975).Google Scholar
- 3.D.J. Rasbash, Theory in the evaluation of fire properties of combustible materials, in 5th International Fire Protection Seminar, p. 113, Karlsruhe, West Germany (1976).Google Scholar
- 4.A. Tewarson, paper submitted to Combustion and Flame.Google Scholar
- 6.S.L. Madorsky, Thermal Degradation of Organic Polymers, Wiley-Interscience, New York (1964).Google Scholar
- 7.D.B. Spalding, The Combustion of Liquid Fuels, in Fourth Symposium (International) on Combustion, p. 847, The Combustion Institute, Pittsburgh (1953).Google Scholar
- 8.I. Glassman, The Mass Burning Rate of Polymeric Materials, The Center for Environmental Studies, Princeton University, Princeton, New Jersey, Report No. 23, (June 1975).Google Scholar
- 9.A. Tewarson, J.L. Lee, and R.F. Pion, The Influence of Oxygen Concentration on Fuel Parameters for Fire Modeling, 18th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, p. 563 (1981).Google Scholar
- 10.H.C. Kung, private communication (November 1978).Google Scholar
- 11.J. de Ris, Fire Radiation—A Review, 17th Symposium (Internal) on Combustion, The Combustion Institute, Pittsburgh, p. 1003, (1979).Google Scholar
- 12.R.L. Alpert, J. de Ris, A.T. Modak, M.K. Mathews, G.H. Markstein, L. Orloff, R.I. Land, E. Farren, J.C. Polo, D.S. Mann, F.B. Kiley, and L. Crudup, Influence of Enclosures on Fire Growth—Vol. I Test Data, Factory Mutual Research Corporation, Norwood, Massachusetts, Technical Report No. 0A0R2.BU-7, (August 1977).Google Scholar
- 13.W.P. Chien and J.D. Seader, Smoke Measurement in a Modified NBS Smoke-Density Chamber, Flammability Research Center/ Department of Chemical Engineering, University of Utah, Salt Lake City, Utah, Report No. FRC/UU-44, UTEC 75-055, (April 1975).Google Scholar