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INTRODUCTION The Committee on Evaluation of Industrial Hazards of the National Materials Advisory Board was charged with assigning classifications to certain chemicals of interest to OSHA according to the classification groups given in the National Electrical Code, Article 500 (NEC 500~. To aid in this task the committee also collected physical and flammability properties of these chemicals and compiled them into a matrix. This work is an extension of earlier work done by the NRC Committee on Hazardous Materials in which flammability properties of chemicals of interest to the U.S. Coast Guard (USCG) were also studied and classified according to NEC 500. This current Matrix of Combustion- Relevant Properties and Classifications of Gases7 Vapors, and Selected Solids includes materials in the earlier study* and the list of chemicals submitted by OSHA as published in the Federal Register, Vol. 39, No. 125, pp. 23541-3 of 27 June 1974, in order to make the Matrix more encompassing and, therefore, more useful. It includes classifications assigned by the committee to materials not previously classified, classifications by the earlier committee (which have been reviewed and updated), and classifications by the NEC 500 and/or proposed classifications by Underwriters Laboratories, Inc. Names of chemicals as used in this Matrix are taken from the earlier USCG list and from the list proposed by OSHA as printed in the Federal Register and are not necessarily the nomenclature consistent with that recommended by The International Union of Pure and Applied Chemistry (IUPAC). Since it has become apparent to the committee that classifications are closely linked to chemical structure, the Matrix is presented and cataloged by chemical families. This should make it easier to classify new materials not now in the Matrix which become of importance or of interest and to include them in future matrices. Accordingly, a summary of tentative classif ications by families is also 1
2 included. The rationale and modus operandi for classifications of the new chemicals were very similar to those used by the Panel on Electrical Hazards of the earlier committee, and the reader is referred to their report for details**. The Matrix-does not represent an exhaust ive coverage of the literature, but it is believed that reliable references ' were used in assembling the data.. It must be recognized that the data presented are for pure materials, and some properties (such as'flash point) may'd.iffer significantly from materials of commerce because of differences in purity. . Although a few.solids are included in the present matrix, the classification of dusts in general is the subject of a separate study and will be reported in a publication to follow this one. Matrix of Electrical and Fire Hazard Properties and Classifications of Chemicals. A report prepared for the Committee on Hazardous Materials of the National Research Council by the Electrical Hazards Panel, Homer W. Carhart, Chairman. National Academy of Sciences, Washington, DC, 1975. NTIS No. AD/A027181/WK. ** Fire Hazard Classification of Chemical Vapors Relative to Explosion-Proof Electrical Equipment, Report IV. A supplementary report prepared by the Electrical -Hazards Panel of the Committee on Hazardous Materials of the National Research Council, Homer W. Carhart, Pane J Chairman, Robert B. Beckman, Chairman. National Academy of Sciences, Washington, DC, 1975. NTIS No. AD/PC026215/LG. .