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Hazardous Material Classification in the United States: History, Problems, and Needs.
Proceedings of the International Symposium on the Explosion Hazard Classification of Vapors, Gases, and Dusts, National Materials Advisory Board, Publication NMAB-447 1987:1-9
Hazardous material classification in the United States was reviewed. The history of hazardous material classification with reference to using electrical equipment or devices in explosive atmospheres was summarized. The National Electrical Code (NEC) was mentioned. The NEC is the accepted standard for all types of electrical installations. Although it is a voluntary, nongovernmental standard, it derives its authority form the fact that local and state governments have based their laws and ordinances on the NEC. Problems with classifying flammable or explosive materials were discussed. Relating material classifications to accepted practices for selecting and installing electrical devices in explosion prone areas was considered. Classifying dusts was discussed. It was noted that the dust classification schemes as developed by the Instrument Society of America do not consider the flammability properties of the dusts. Protection against dust explosions in North America has been based on designing electrical devices so that the dust does not come into contact with possible ignition sources. Purposes of the symposium as they relate to classifying combustion hazards of gases and explosion hazards of dusts were discussed.
Occupational-health; Industrial-safety; Dust-explosions; Combustible-gases; Electrical-equipment; Standards; Explosion-prevention; Explosive-atmospheres;
Proceedings of the International Symposium on the Explosion Hazard Classification of Vapors, Gases, and Dusts, National Materials Advisory Board, Publication NMAB-447
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division