Fire hazards

Most organic solvents are readily volatile and combustible, and their vapors form explosive mixtures with air. The fire hazard of solvents depends on their volatility and flash point (Section 14.3.7). 

In Germany, the Verordnung uber brennbare Fliissigkeiten, VbF (Directive on Combustible Liquids) divides solvents into danger classes  

Class A I water-insoluble, flash point 21 C Class All water-insoluble, flash point 21-55 C Class A 111 water-insoluble, flash point 55-100 C 

Class B Hash point 21 C in the case of liquids that are miscible in all proportions with water 

In the United States substances are subdivided according to their flash points  

Fluoropolymers do not ignite easily and do not sustain flame. They ean decompose in a flame and 

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Thus, against this measure, the fire hazard is 3.5 times larger for operation at 150°C compared with operation at 100 C. 

FIRE HAZARDS ATTENDING THE DISTILLATION OF INFLAMMABLE SOLVENTS... 

Finely divided uranium metal, being pyrophoric, presents a fire hazard. 

The highest G-ratios are obtained when grinding with straight oil coolants. Such oils reduce power, increase maximum depth of cut, and produce smoother finishes. Disadvantages include inabiUty to remove heat from the work, oil mist in the work area, fire hazard, and tendency to hold grinding swarf (fine metal chips and abrasive particles produced in the grinding process) in suspension. Reference 51 is an excellent survey article for grinding fluids. 

Health and Safety Factors. Because of their high vapor pressures (methyl vinyl ether is a gas at ambient conditions), the lower vinyl ethers represent a severe fire hazard and must be handled accordingly. Contact with acids can initiate violent polymerization and must be avoided. Although vinyl ethers form peroxides more slowly than saturated ethers, distillation residues must be handled with caution. 

The relatively low flash points of some acrylates create a fire hazard. Also, the ease of polymerization must be home in mind in ah. operations. The lower and upper explosive limits for methyl acrylate are 2.8 and 25 vol %, respectively. Corresponding limits for ethyl acrylate are 1.8 vol % and saturation, respectively. All possible sources of ignition of monomers must be eliininated. 

The assessment of the contribution of a product to the fire severity and the resulting hazard to people and property combines appropriate product flammabihty data, descriptions of the building and occupants, and computer software that includes the dynamics and chemistry of fires. This type of assessment offers benefits not available from stand-alone test methods quantitative appraisal of the incremental impact on fire safety of changes in a product appraisal of the use of a given material in a number of products and appraisal of the differing impacts of a product in different buildings and occupancies. One method, HAZARD I (11), has been used to determine that several commonly used fire-retardant—polymer systems reduced the overall fire hazard compared to similar nonfire retarded formulations (12). 

V. Babrauskas and co-workers. Fire Hazard Comparison of Fire-FetardedandISion-Fire-FetardedProducts, NBS Special Pubhcation 749, National Bureau of Standards, Gaithersburg, Md., 1987. 

CAL 133. California Technical Bulletin 133 is a test of the fire hazard associated with upholstered furniture (22). The test is carried out by igniting a standard fire source directiy on the piece of furniture being tested. In the most recent version of the test, the fire source is a gas flame. Smoke, heat, and toxic gas emissions are measured dufing the test. A related test, BS 5852, uses various wooden cribs as the fire source (23). 

Reduction of Fire Hazard Using Fire Retardant Chemicals, Fire Retardant Chemicals Association, Lancaster, Pa., 1989. 

This hydrolysis reaction is accelerated by acids or heat and, in some instances, by catalysts. Because the flammable gas hydrogen is formed, a potential fire hazard may result unless adequate ventilation is provided. Ingestion of hydrides must be avoided because hydrolysis to form hydrogen could result in gas embolism. 

Main advantages of water inks include excellent press stability, printing quality, heat resistance, absence of fire hazard, and the convenience and economy of water for reduction and wash-up. 

Methanol is stable under normal storage conditions. Methanol is not subject to hazardous polymerization reactions, but can react violendy with strong oxidizing agents. The greatest hazard involved in handling methanol is the danger of fire or explosion. The NFPA classifies methanol as a serious fire hazard. 

Fire Hazard Properties oJFlammahle Eiquids, Gases, and Volatile Solids, NFPA 325M, National Fire Protection Association, Quincy, Mass., 1991. 

Health nd Safety Factors. The mononitrochlorobenzenes are toxic substances which may be absorbed through the skin and lungs giving rise to methemoglobin. Their toxicity is about the same as or greater than that of nitrobenzene. The para isomer is less toxic than the ortho isomer, and the maximum allowable concentration that has been adopted for -nitrochlorobenzene is 1 mg/m (0.1 ppm) (6). The mononitrochlorobenzenes are moderate fire hazards when exposed to heat or flame. They ate classified by the ICC as Class-B poisons. The same handling precautions should be used for these compounds as are used for nitrobenzene. 

Methyl-1-pentene [691-37-2] is alight, colorless, flammable fiquid its physical constants are also given in Table 1. It is an irritant and, in high concentrations, a narcotic. Like 1-butene, this chemical compound has a low flash point and represents a significant fire hazard when exposed to heat, flame, or oxidizing agents. 

The flash point of aniline (70°C) is well above its normal storage temperature but, aniline should be stored and used in areas with minimum fire hazard (70). Air should not be allowed to enter equipment containing aniline Hquid or vapor at temperatures equal to or above its flash point. 

Metal deck assembhes are tested by UL for under-deck fire hazard by usiag their steiaer tunnel (ASTM E84). The assembly, exposed to an under-deck gas flame, must not allow rapid propagation of the fire down the length of the tuimel. FM uses a calorimeter fire-test chamber to evaluate the hazard of an under-deck fire. The deck is exposed to a gas flame and the rate of heat release is measured and correlated to the rate of flame propagation. A different FM test assesses the damage to roof iasulations exposed to radiant heat. 

Both functional and decorative coatings can be appHed to paper from latices. The aqueous dispersions can be used on conventional paper converting machinery which usually cannot handle hot melts and solvent coatings. The lack of fire hazard because of absence of solvents is an added advantage of the latex system. 

Health and Safety Factors. The strontium ion has a low order of toxicity, and strontium compounds are remarkably free of toxic hazards. Chemically, strontium is similar to calcium, and strontium salts, like calcium salts, are not easily absorbed by the intestinal tract. Strontium carbonate has no commonly recognized hazardous properties. Strontium nitrate is regulated as an oxidizer that promotes rapid burning of combustible materials, and it should not be stored in areas of potential fire hazards. 

For dammable and combustible hquids, dash point is the primary basis for classifying the degree of fire hazardousness. NFPA Classifications 1, 2, and 3 designate the most to the least fire hazard hquids, respectively. In essence, low dash point hquids ate high fire hazard hquids. 

Thiophene and 3-methylthiophene are Hsted on the TSCA chemical substances inventory. Thiophene is regulated as a hazardous material under OSHA and also regulated under the Clean Air Act, Section 110, 40 CFR 60.489, but there are no exposure limits or controls set for 3-methylthiophene. Both materials are regulated under sections 311/312 of the Superfund Amendments and Reauthorization Act, 1986 (SARA), as materials with an acute health and fire hazard, and under the Resource Conservation and Recovery Act, as ignitable hazardous wastes (DOOl). 

Flash Point (ASTMD92). The Cleveland open cup method is most commonly used although the Tag open cup (ASTM D3143) is apphcable to cutbacks. Flash point is an indication of fire hazard and the test is frequendy used to indicate whether a given product has been contaminated with materials of lower dash point. 

Organic compounds of bromine usually resemble their chlorine analogues but have higher densities and lower vapor pressures. The bromo compounds are more reactive toward alkaUes and metals brominated solvents should generally be kept from contact with active metals such as aluminum. On the other hand, they present less fire hazard one bromine atom per molecule reduces flammabiUty about as much as two chlorine atoms. 

Methyl bromide is nonflammable over a wide range of concentrations in air at atmospheric pressure and offers practically no fire hazard. With an intense source of ignition, flame propagation within a narrow range from 13.5 to 14.5% by volume has been reported. The material has no flash point. Thermal decomposition in a glass vessel begins somewhat above 400°C. 

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