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Author
Ohlemiller, T. J. | Shields, J. R.
Title
Behavior of Mock-Ups in the California Technical Bulletin 133 Test Protocol: Fabric and Barrier Effects.
Coporate
National Institute of Standards and Technology, Gaithersburg, MD
Report
NISTIR 5653, May 1995, 76 p.
Distribution
Available from National Technical Information Service
Keywords
fabrics | fire barriers | cone calorimeters | furniture | furniture calorimeters | heat release rate | thermoplastic fabrics
Abstract
Twenty-seven material combinations (seven fabrics, four barriers and two polyurethane foams) were tested in four cushion mock-up form in accord with California Technial Bulletin 133 using a furniture calorimeter. These same material combinations were also tested in triplicate, mainly at 35 kW/m², in the Cone Calorimeter. Both mock-up and Cone sample behavior were recorded on video to facilitate behavioral comparisons of the samples; distinct differences were noted for thermoplastic fabrics. Heat fluxes were also measured on both scales; the effective "external" flux in full-scale can exceed 50 kW/m². The mock-up behavior always comprised at least a heat release peak during the 80 second gas burner exposure; it often included a later and larger peak as well. The first peak could not be adequately predicted by average heat release data from the Cone. A dimensional analysis suggested a possible dependence on four additional parameters, three of which can be obtained from the Cone. A statistical fit of the available data to these more complex types of correlations appears to work best for charring fabrics; it helps improve the correlation for all types of fabrics but two material combinations were outliers. The second heat release peak in the mock-up tests is attributable to a "basal melt fire" mechanism; efforts to correlate this behavior with Cone results have been limited thus far and show little success.