Behavior of Mock-Ups in the California Technical Bulletin 133 Test Protocol: Fabric and Barrier Effects.
Behavior of Mock-Ups in the California Technical
Bulletin 133 Test Protocol: Fabric and Barrier Effects.
(3462 K)
Ohlemiller, T. J.; Shields, J. R.
NISTIR 5653; 76 p. May 1995.
Available from:
National Technical Information Service
Order number: PB95-231585
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.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899