Page:NBS Circular 553.djvu/12

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The ISCC-NBS Method of Designating Colors and A Dictionary of Color Names Kenneth L. Kelly and Deane B. Judd In 1939 there was published a Method of Designating Colors as a solution of the problem proposed by the first chairman of the Inter-Society Color Council, E. N. Gathercoal, who said: "A means of designating colors in the United States Pharmacopoeia, in the National Formulary, and in general pharmaceutical literature is desired; such designation to be sufficiently standardized as to be acceptable and usable by science, sufficiently broad to be appreciated and used by science, art and industry, and sufficiently commonplace to be under- stood, at least in a general way, by the whole public." This method was developed with the assistance of the American Pharmaceutical Association following plans outlined in 1933 by the Inter-Society Color Council. As a result of suggestions of the member bodies and individual members of the ISCC, a revision of the proposed system was made and approved by the Council in June 1949 and recommended for use in general color description. The revised ISCC-NBS color designations are defined in Munsell terms by 31 name charts, one for each of 31 ranges of Munsell hue. The ISCC-NBS equivalents of 7,500 color names previously defined by reference to 11 different sets of material standards have been de- termined and listed both alphabetically and by ISCC-NBS color designation to form a dictionary of color names. 1. History In 1932 the first chairman of the Inter-Society Color Council (ISCC), E. N. Gathercoal, proposed that the Council develop "a means of designating colors in the United States Pharmacopoeia, in the National Formulary, and in general literature... such designation to be sufficiently standardized as to be acceptable and usable by science, sufficiently broad to be appreciated and used by science, art and industry, and sufficiently commonplace to be under- stood, at least in a general way, by the whole public." This problem originally was referred by the ISCC to its Committee on Measurement and Specification which, under the chairmanship of I. H. Godlove, presented several reports surveying available methods of color designation. The 1933 annual report of this committee [22]¹ included the outline of a recom- mended system of color designations. These recom- mendations were approved by the Council and followed by the authors in developing this system of color designations, in setting the color boundaries, and in working out methods of applying the system to drugs and chemicals in various forms. The Inter-Society Color Council in 1939 formally ap- proved by letter ballot [20], and recommended to the National Formulary Revision Committee and to the United States Pharmacopoeial Convention, the method described in NBS Research Paper RP1239 [27] Since 1939, a number of suggestions for revision of this system of color names have been received, especially from Margaret Hayden Rorke, Man- aging Director of the Textile Color Card Asso- ciation (TCCA), which have aided the authors in 1 Figures in brackets indicate the literature references on pages 13 and 14. making the present revision. An ISCC committee consisting of Beck, Clark, Foss, Godlove, Granville, Judd (Chairman), Kelly, Nickerson, Reimann, Rorke, and Stearns was formed in 1947 to study these suggestions and make recommendations as to name and boundary changes. The changes which are embodied in this revision have been approved by letter ballot [21] for use wherever applicable by all of the 19 Member Bodies and the Individual Member Group of the ISCC. 2. Scope The color designations have been extended to apply under the recommended conditions of lighting and viewing not only to opaque surfaces such as prepared powder samples or solids but also to clear or cloudy liquids or solids, microscopic structures and fluores- cent samples. The gamut of color names has been extended to cover the colors of clear and cloudy light- transmitting samples by substituting colorless for white, faint pink for pinkish white, faint yellow for yellowish white, faint green for greenish white, faint blue for bluish white, and faint purple for purplish white [20]. It must be remembered that the Munsell renota- tions and the ISCC-NBS color names used in this system are determined under the conditions of aver- age daylight (CIE source C), 45° illumination, and normal viewing (see section 6.1.2). In determining Munsell approximate renotations by comparison with the Munsell scales, the sample must be about the same size as the Munsell chips and must be viewed on a white or light gray background. These con- ditions will be referred to in this paper as "recom- mended conditions of lighting and viewing" or simply