Flammability category

A collection of databases of chemicals and of functional groups which rank chemicals and groups relative to their reactivity, stability, toxicity, and flammability categories. This would assist in the evaluation of the potential benefits of substituting one, somewhat safer, chemical for another. 

The foamed materials are classified into the following flammability categories ... 

Table 5.1.2.3 shows the chemical and flammability properties of many solvents that are commonly used in laboratories. You ll note that most of the ratings of these chemicals put them in the extremely flammable or highly flammable categories. 

Methane has a GHS flammability rating of 1 (NFPA rating of 4), putting it in the extremely flammable category. A methane leak in a lab is extremely dangerous. The lower explosive level (LEL) is 4.5% and the upper explosive level (UEL) is 16.5%. A sulfur compound, often ethyl mercaptan or a mixture of mercaptans, is added to natural gas to give it an unpleasant odor and allow for easy detection. The complete combustion of methane produces carbon dioxide and water ... 

Note Aerosols not submitted to the flammability classification procedures in this Appendix shall be classified as extremely flammable (Category 1). 

In the past, hazardous wastes were often grouped into the following categories (1) radioactive substances, (2) chemicals, (3) biological wastes, (4) flammable wastes, and (5) explosives. The chemical cate-goiy included wastes that were corrosive, reactive, and toxic. The principal sources of hazardous biological wastes are hospitals and biological-research facilities. 

These markings provide a general idea of the hazards of a material and the severity of these hazards as they relate to handling, fire protection, exposure, and control. This standard is not applicable to transportation or to use by the general public. It is also not applicable to chronic exposure. For a full description of this standard, refer to NFPA 704. The system identifies the hazards of a material in four principal categories health, flammability, reactivity, and unusual hazards such as reactivity with water. 

Landfill disposal of certain categories of solid waste may result in gas generation, mainly methane, and a highly polluted leachate. The methane may be drawn off, to avoid a flammable hazard on- or off-site. The leachate is pumped off for treatment. 

The testing of chemicals/wastes to establish the nature of their hazard capacity/threat in accordance with regulatory requirements falls into four categories (1) reactivity, (2) ignitability/flammability, (3) corrosivity, and (4) EP toxicity. Commercial chemical products, specific wastes, and wastes from specific processes may be listed as hazardous wastes because they are known to present toxic hazards in the manner of the tests above and/or are known to present serious toxic hazards to mammals/humans. In the discussion to follow, various chemical groups will be examined primarily in the context of reactivity, ignitability, and corrosivity. 

Poison A gas explosives-A/B, organic peroxide, flammable solid, materials dangerous when wet, chlorine, flourine, anhydrous ammonia, radioactive materials, NFPA 3 4 for any categories including SF>ecial hazards. PCB s fire, DOT inhalation hazzird, EPA extremely hazardous substances, and cryogenics. 

Other than reactive metals explosions, which do not truly fall in the types noted above, the two main categories of explosions are flammable gases, liquids/vapors, and dusts. Because their sources are different, they cannot be treated in the same manner for discussion. 

Flammable CHS Category 1 - CHS Category 2 - No basis for concern identified... 

Are raw process and waste materials stored in a safe and appropriate manner for example, are bulk acids in tanks bunded with secondary containment, are flammable materials in a fire-protected, ventilated store, are powders and pellets in areas fitted with dust extraction segregation of noncompatible materials Provide details of existing storage arrangements, inducing plans and specifications. Identify risk areas. Identify the risk category. 

Administration, Improved Flammability Standards for Materials Used in the Interiors of Transport Category Airplane Cabins Final Rule. 14 CFR Parts 25 and 121. Federal Register, 53 (165) pp. 32564-81, Aug. 25,... 

Class I, II and III are also used by NFPA to define the range of certain materials in categories based mainly on flash points. Class II and III materials generally do not provide sufficient vapors to require specification of an electrically classified area, so areas are only defined by Class I flammable materials. 

Hazard Class A series of nine descriptive terms that have been established by the UN Committee of Experts to categorize the hazardous nature of chemical, physical, and biological materials. These categories are flammable liquids, flammable solids, explosives, gases, oxidizers, radioactive materials, corrosives, poisonous and infectious substances, and dangerous substances. 

Diffusion flames can best be described as the combustion state controlled by mixing phenomena—that is, the diffusion of fuel into oxidizer, or vice versa—until some flammable mixture ratio is reached. According to the flow state of the individual diffusing species, the situation may be either laminar or turbulent. It will be shown later that gaseous diffusion flames exist, that liquid burning proceeds by a diffusion mechanism, and that the combustion of solids and some solid propellants falls in this category as well. 

The hazards common to the petrochemical industry involve flammable liquids and gases. Many of the fire models that can be used to assess these hazards fall under the categories mentioned above. The models discussed below are fire models or conglomerate models that have been designed specifically to address fire hazards presented in the petrochemical industry. 

The use of high-sihcon iron in flammable-fluid service or in Category M fluid service is prohibited by the code. 

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