Fire hazard methods of classification

Production and Shipment. Estimated adiponitrile production capacities in the U.S. in 1992 were about 625 thousand metric tons and worldwide capacity was in excess of lO metric tons. The DOT/IMO classification for adiponitrile is class 6.1 hazard, UN No. 2205. It requires a POISON label on all containers and is in packing group III. Approved materials of constmction for shipping, storage, and associated transportation equipment are carbon steel and type 316 stainless steel. Either centrifugal or positive displacement pumps may be used. Carbon dioxide or chemical-foam fire extinguishers should be used. There are no specifications for commercial adiponitrile. The typical composition is 99.5 wt % adiponitrile. Impurities that may be present depend on the method of manufacture, and thus, vary depending on the source. 

After studying these parameters, we will describe and discuss the most important classification methods before suggesting a new quantitative classification method for the fire hazard of a chemical substance. 

Underwriters Laboratories, Inc., Subject 723, Standard Test Method for Fire Hazard Classification of Building Materials, August 1950. 

Am. Soc. Testing Materials, Designation E 84-50T, Tentative Method of Fire-Hazard Classification of Building Materials. ... 

There are a large number of different methods used for bench-scale assessment of combustion toxicity, and the applicability of test data to lire hazard assessment is not always clear. Obviously, toxic potency data should not be used in isolation but should either be a part of a classification scheme or as part of the input to lire risk and lire safety engineering assessments. It is important that uncertainty or confidence limits should be used with toxic potency data, because they are often relatively large. Fire effluent toxic potency does not have a unique value but is a function of the material and the fire conditions, particularly temperature and oxygen availability in the fire zone, and also the fire environment (enclosure, geometry, and ventilation). To assess the fire hazard, toxic potency data must be relevant to the end use fire situation, and the fire condition, which can be defined using the ISO classification of fire stages. 

Thus the flash point is used primarily as an index of fire hazards. Consequently, most industry specifications or classifications place limits on the flash point to ensure compliance with fire regulations, insurance, and legal requirements because it is essential that the fuel is safe to transport and store. Generally, because of its distillation characteristics, fuel oil should not contain any volatile or flashable constituents. Nevertheless, the occasion might arise when application of test methods to determine the flash point might be applicable. 

The hazard classifications and methods of protection of various materials identified in this Guideline may not be consistent with the classifications, protection methods or mitigation means found in the applicable building construction or fire codes. Compliance with building codes will not always ensure an adequate warehouse design. They may, in fact, provide only minimum protection. The appropriate level of protection beyond that required by code or regulation is a business decision. 

This test method was developed as a result of need for flammability standard for carpets and rugs to protect the public against fire hazards [52]. Consequently, several carpet systems were tested by this standard [52-54]. This standard test method (ASTM E 648) is specified for the classification of the interior floor finish in buildings in the NFPA 101 Life Safety Code [55] ... 

Predictive hazard evaluation procedures may be required when new and different processes, designs, equipment, or procedures are being contemplated. The Dow Fire and Explosion Index provides a direct method to estimate the risks in a chemical process based upon flammability and reactivity characteristics of the chemicals, general process hazards (as exothermic reactions, indoor storage of flammable liquids, etc.) and special hazards (as operation above the flash point, operation above the auto-ignition point, quantity of flammable liquid, etc.). Proper description of this index is best found in the 57-page Dows Fire and Explosion Index, Hazard Classification Guide, 5 th ed., AIChE, New York, 1981. 

The Fire Services Law was revised in May, 1988, and the listing of hazardous materials has been also revised as shown in Table 1.1. The new definition of hazardous materials under the revised Fire Services Law employs modem classification methods utilizing special evaluation techniques. The following quotation comes from the official gazette and demonstrates the principle of the revision 2 5 . ... 

There are three main categories of hazards namely, fire and explosion hazards, health hazards and environmental hazards. Different evaluation methods exist for each category. Not being experts in every evaluation method, the authors will refer only to the evaluation methods which are generally used. Evaluation methods according to the U.N. classification system, which covers a wide range of hazardous materials, are explained. 

Classification and methods for the evaluation of hazardous materials are briefly described in Section 1.3. Testing methods for reactive chemical substances are described in Chapter 3. This chapter discusses what methods should be actually combined for testing materials mainly under the Fire Protection Law and for voluntary in-firm confirmation. 

Among the ANSI standards is the National Electrical Code (NEC) which is directed at the elimination or control of electrical hazards. It defines the classification of areas according to the degree of hazard possibly foimd in the atmosphere and prescribes wiring methods, grounding, control, etc. These factors are important in motor selection. The NEC is a product of the National Fire Protection Association (NFPA). 

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