Ignitability 632 INDEX

One other characteristic linked to the quality of combustion is called the CIl (Calculated Ignition Index) and is expressed by the equation / ... 

It is impractical to determine the cetane number of residual fuels in the ASTM D-613 cetane engine. Because of this, the Calculated Carbon Aromaticity Index and the Calculated Ignition Index were respectively developed by Shell and BR These values can be determined from the following equations where d = Density in kg/m3 59°F (15°C) and v = Viscosity in cSt 122°F (50°C). 

Australia AS 1530 Part 3 - ignitability index. Specified in Australian Building Regulations. A 600x450 mm specimen is mounted vertically and moved at a predetermined rate towards a radiant gas burner mounted opposite and parallel to it. The Ignitability Index is calculated from the time taken for the specimen to ignite. The same apparatus is used to measure Spread of Flame and Heat Release. 

The relationship between the ignition index for epoxy polymers in the presence of (C6H5)3Sb and the nature of the oxidizer (O2 and N2O) confirms the gas phase mechanism for the effect of this flame retardant. 

Another characteristic used for some time to measure the propensity of a diesel fuel for auto-ignition, is the Diesel Index (Dl). This is defined by the relation ... 

Magnesium hydroxide is white, has an average particle size of 1—10 p.m, density of 2.36 g/mL, refractive index of 1.58, and Mohs hardness of 2.00. Water loss on ignition is 31.8 wt %. Magnesium hydroxide contains 1.0 wt % Ca(OH)2 and is made by Solem Industries and Morton Thiokol (25). 

Other terms relating to physical properties include viscosity refractive index pour point, ie, the lowest temperature at which the oil flows flash point, ie, the temperature at which the oil ignites and aniline point, ie, the minimum temperature at which equal volumes of oil and aniline are completely miscible. These are determined under defined conditions estabHshed by ASTM. 

The UL flammability ratings describe the relative ease of ignition and combustibiUty of plastics. Tests include the measurement of flame propagation, time to self-extinguish, melt and drip with and without flame, and oxygen indexes. Some engineering plastics, eg, polyetherimides, are, as ranked by this test, inherently nonflammable. Others can be made nonflammable by compounding with flame retardants (ERs) such as bromine... 

Limiting oxygen index Temperature of self-ignition... 

Other important properties include Hash point, volatility, viscosity, specific gravity, cloud point, pour point, and smoke point. Most of these properties are related directly to the boiling range of the kerosene and are not independently variable. The flash point, an index of fire hazard, measures the readiness of a fuel to ignite when exposed to a flame. It is usually mandated by law or government regulation to be 120° or 130° F (48° or 72° C), Volatility, as measured... 

Cetane Number is a numerical indication of a fuel s (kerosene, dic.sel, heating oil) ignition quality. Cetane number is measured in a single-cylinder engine, whereas cetane index is a calculated value. 

The oxygen index method was used to demonstrate synergy. This method measures ease of ignition, that is the facility with which a material or it s pyrolysis products can be ignited under given conditions of temperature and oxygen concentration. This test is indicative of the intrinsic flamability of a material but... 

Ignition and autoignition temperatures, lower explosion limit and oxygen index were determined for the powdered butyral in relation to dispersibilty and viscosity. 

Compounds which are considered to be unusually hazardous in a fire context because of their low flash points (below 25°C) or auto-ignition temperatures (below 225°C) are included in the table. The names used are those titles in the text of Section 1 which are prefixed with a dagger. Synonyms may be found either in Section 1 or in the alphabetical index of chemical names and synonyms in Appendix 4. Boiling points are given for those compounds boiling below 50°C. 

In flame retarding nonwovens, the contribution of components may not be additive. Rather, the interaction of binder, flame retardant, and substrate is critical in the performance of the flame retardant nonwoven. Similarly, the flammability of a binder film or the flammability of a flame retardant coated woven cloth often do not predict the flame retardancy of the same binder or flame retardant on a nonwoven substrate of rayon or polyester. Actual data on a nonwovens substrate is the only accurate measure of a system s flame retardancy. For this study, two widely used substrates were selected. The first, lightweight rando rayon, is representative of material used in nurse caps, surgeon s masks, and miscellaneous coverstock. This material is constructed of 1 1/2 denier fiber, weighs 1 1/2 ounces per square yard, and is relatively dense web. Rayon as a material is water absorbent, burns rather than melts, and is readily flammable. This fiber ignites around 400°C(2) and has an oxygen index of about 19.0. Certain binders adhere well to rayon while others do not. Apparently, this lack of affinity for the substrate affects flame retardancy, as will be demonstrated later. 

Oxygen-Index Measurements. The measurement of oxygen-index was performed by bottom ignition, as discussed by Stuetz (11). 

Films containing about 10% CIRh(PPh3)3 in PMMA were prepared and subjected to oxygen index, TGA, and DSC measurements. The oxygen index, bottom ignition (1 1), increases from about 14 for pure PMMA to about 20 for the rhodium compound in PMMA. TGA analysis indicates that about 25% of the sample is non-volatile at 600°C and the glass transition temperature increases by about 15°C by DSC. 

Total additive loadings rarely exceed 1% of the finished resin. The criteria for ignition resistance are based on oxygen index and UL-94 ratings. The mode of action of the flame retardants is reported to be consistent with that of aromatic sulfonates as proposed by Webb (27). 

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