Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

National Bureau of Standards smoke

The National Bureau of Standards smoke density chamber (Figure 7) is a more recent technique used to evaluate smoke. This chamber can be used to measure adequately the smoke produced from untreated and fire-retardant-treated wood (27, 28). This method has three advantages over the tunnel method (1) application to a variety of room situations, burning areas, and light-path lengths, (2)... [Pg.538]

Acrylics are also similar to cotton in smoke generation. National Bureau of Standards smoke cabinet results are shown in Figure 12.48 for acrylic, modacrylic, nylon, PVC, cotton, and wool [376]. These data show wool to give the highest smoke density while nylon and PVC give the lowest, under these burning conditions. The modacrylics are actually somewhat worse in smoke generation than acrylics. The thermal and flammability behavior of textile materials has been reviewed in detail by Rebenfeld et al. [377], Lewin et al. [378], and Lewin [379]. [Pg.916]

American National Bureau of Standards Smoke Chamber... [Pg.286]

Smoke emission is measured in an air colunrn above a burning specimen in a National Institute of Standards Technology (previously the National Bureau of Standards) smoke chamber (see Fig. 4-28). In the NIST test a specified area of plastic is exposed to heat under flaming conditions, with smoke measurements being reported as specific optical density. This is dimensionless value represents the optical density measured over a unit of path length within a chamber of unit volume that is produced from a test specimen of... [Pg.287]

One particularly widely used test is the National Bureau of Standards (NBS) smoke chamber test. This provides a measure of the obscuration of visible light by smoke in units of specific optical density. The NBS smoke test can be run in either of two modes ... [Pg.109]

The traditional way in which smoke obscuration has been measured is by determining the maximum smoke density (or the specific maximum smoke density) by means of a smoke density chamber developed by the National Bureau of Standards (NBS smoke chamber, ASTM E662). This instrument measures the obscuration inside a static 500 L chamber, after a sample has been exposed, vertically, to a 2.5 W/cm2 radiant source. [Pg.522]

Lee, T.G., "The Smoke Density Chamber Method for Evaluating the Potential Smoke Generation of Building Materials," 1973, National Bureau of Standards (National Institute of Standards and Technology), Gaithersburg, MD, Technical Note, 757, ASTM E-662). [Pg.565]

The National Bureau of Standards (NBS, now National Institute for Standards and Technology, NIST) fire and smoke transport model, F.A.S.T., version 18.3, was used to generate the information concerning the temperatures and gas concentrations. This is a zone model which predicts the formation of two layers in each compartment. [Pg.604]

Considerable research is underway by various institutions and agencies and by industry on the physiological and toxicological effects of smoke and gaseous products. Of particular note are the extensive research programs at the University of Utah under the direction on I. N. Einhorn (44,48), at Johns Hopkins University under R. M. Fristrom (38,50), and at the National Bureau of Standards under M. M. Birky (51). [Pg.99]

Chapter 6 Smoke test. The test is based on the National Bureau of Standards (NBS, now NIST, National Institute of Standards and Technology) smoke density chamber, which has also been standardized as ASTM E 66239 (see also Section 4.1.1). The test exposes a vertical test specimen ca. 75 mm x 75 mm (3 in. x 3 in.) to an incident radiant heat flux of 25kW/m2, from a radiant heat burner for 4 min, in the presence of an open-flame pilot burner. The test applies to the same materials as the heat release rate test. The acceptance criterion is an average maximum specific optical density of smoke that does not exceed 200 (no units). [Pg.599]

Many test methods for the determination of the acute toxicity of combustion products from materials and products have been developed over the last two decades and continue to be developed and/or improved. In 1983, 13 of the methods published up to that time were evaluated by Arthur D. Little, Inc. to assess the feasibility of incorporating combustion toxicity requirements for building materials and finishes into the building codes of New York State. On the basis of seven different criteria, only two methods were found acceptable. These two methods were the flow-through smoke toxicity method developed at the University of Pittsburgh and the closed-system cup furnace smoke toxicity method developed at NIST (known at that time as the National Bureau of Standards (NBS)). Standard Reference Materials and protocols (SRM 1048 and SRM 1049) were developed at NIST and are available to the users of these methods to provide assurance that they are performing the methods correctly (see Relevant Websites ... [Pg.649]

Table XI. Smoke Density. National Bureau Of Standards Test... Table XI. Smoke Density. National Bureau Of Standards Test...
Several methods have been proposed for the determination of the smoke density. Reproducible values are obtained with the laboratory method worked out by the National Bureau of Standards, whereby a specimen of 7.6 X 7.6 cm is heated by radiation. The smoke density is then measured optically. [Pg.145]

FAA smoke density (minimum light transmittance) 0/ /o National Bureau of Standards, NFPA 258, specimen thickness = 1.3-1.5 mm 92 (smoldering) 6 (flaming) (8,9)... [Pg.263]

The XP-2 chamber was further developed by the US National Bureau of Standard (NBS). This NBS chamber as standardized in ASTM E 662-1979 has become the most wide-spread test apparatus in the United States. In this method, the light transmittance is again measured for calculating the specific optical density of the smoke generated on the following theoretical basis ... [Pg.287]

Gross, D., Loftus, J. J., Lee, T. G. and Gray, V. E. Smoke and Gases Produced by Burning Aircraft Interior Materials. Building Science Series, 18. National Bureau of Standards, 1968... [Pg.333]

Fire requirement Minimum ATH required Dispersion viscosity National Bureau of Standards (NBS) Smoke (Dmax)... [Pg.80]

The Cone Calorimeter was based on a design by Vytenis Babrauskas (Fire Research, National Bureau of Standards) in the early 1980s [4]. This apparatus allows simultaneous and continuous determinations to be made of heat release rate, smoke production rate, mass loss rate and concentration of the various combustion gases formed. It is capable, at the same time, of being used to obtain ignition, heat of combustion and soot production data for the materials tested. As an example, PP has a rate of heat release maximum of 1800 kW/m (heat flux = 50kW/m thickness of the sheet = 3 mm). [Pg.257]

Until recently, one of the main tests was the National Bureau of Standards (NBS) smoke chamber (ASTM E662) [13]. In this test, a vertical sample is decomposed under radiant heat in a sealed cabinet and the build up of optical density is monitored. The test can be run under both smouldering and flaming conditions, depending on whether a pilot ignition flame is present. [Pg.268]

In 1988, the National Bureau of Standards [now the National Institute of Standards and Technology (NIST)] ran room combustion tests comparing flame retardant with non-flame retardant plastics used in printed wiring boards, television set and business machine enclosures, cables, and upholstered furniture. The results showed that flame retardant materials allow more than a 15-fold longer escape time, 75% less heat release, significantly less smoke, and a lower concentration of toxic gases. Fire retardants decrease toxicity in fires. The effect is due to a decrease in the amount of burning material. ... [Pg.2]


See other pages where National Bureau of Standards smoke is mentioned: [Pg.296]    [Pg.795]    [Pg.41]    [Pg.210]    [Pg.296]    [Pg.795]    [Pg.41]    [Pg.210]    [Pg.98]    [Pg.853]    [Pg.192]    [Pg.773]    [Pg.90]    [Pg.70]    [Pg.217]    [Pg.287]    [Pg.3287]    [Pg.501]    [Pg.149]    [Pg.524]    [Pg.456]    [Pg.359]   


SEARCH



National Bureau

National Bureau of Standards

National Bureau of Standards smoke chamber

National Standards

Of smoke

Standards, National Bureau

© 2024 chempedia.info