C |5 ,</i 
 
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 152 
 
 COORDINATED COLOR IDENTIFICATIONS 
 FOR INDUSTRY 
 
 TH J B HE L 
 
 stLT NSVLVAN,ast ' 
 
 ATE CO >-i-EGE, PENNSYLVANIA 
 
 KENNETH L. KELLY 
 
 U. S. DEPARTMENT OF COMMERCE 
 NATIONAL BUREAU OF STANDARDS 
 
THE NATIONAL BUREAU OF STANDARDS 
 Functions and Activities 
 
 The functions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as 
 amended by Congress in Public Law 619, 1950. These include the development and maintenance of the na- 
 tional standards of measurement and the provision of means and methods for making measurements consistent 
 with these standards; the determination of physical constants and properties of materials; the development of 
 methods and instruments for testing materials,- devices, and structures; advisory services to government agen- 
 cies on scientific and technical problems; invention and development of devices to serve special needs of the 
 Government; and the development of standard practices, codes, and specifications. The work includes basic 
 and applied research, development, engineering, instrumentation, testing, evaluation, calibration services, 
 and various consultation and information services. Research projects are also performed for other government 
 agencies when the work relates to and supplements the basic program of the Bureau or when the Bureau's 
 unique competence is required. The scope of activities is suggested by the listing of divisions and sections 
 on the inside of the back cover. 
 
 Publications 
 
 The results of the Bureau's research are published either in the Bureau's own series of publications or 
 in the journals of professional and scientific societies. The Bureau itself publishes three periodicals avail- 
 able from the Government Printing Office: The Journal of Research, published in four separate sections, 
 presents complete scientific and technical papers; the Technical News Bulletin presents summary and pre- 
 liminary reports on work in progress; and Basic Radio Propagation Predictions provides data for determining 
 the best frequencies to use for radio communications throughout the world. There are also five series of non- 
 periodical publications: Monographs, Applied Mathematics Series, Handbooks, Miscellaneous Publications, 
 and Technical Notes. 
 
 A complete listing of the Bureau's publications can be found in National Bureau of Standards Circular 
 460, Publications of the National Bureau of Standards, 1901 to June 1947 ($1.25), and the Supplement to Na- 
 tional Bureau of Standards Circular 460, July 1947 to June 1957 ($1.50), and Miscellaneous Publication 240, 
 July 1957 to June 1960 (Includes Titles of Papers Published in Outside Journals 1950 to 1959) ($2.25); avail- 
 able from the Superintendent of Documents, Government Printing Office, Washington 25, D. C. 
 
NATIONAL BUREAU OF STANDARDS 
 
 technical ^iote 
 
 152 
 NOVEMBER 1962 
 
 COORDINATED COLOR IDENTIFICATIONS 
 FOR INDUSTRY 
 
 Kenneth L. Kelly 
 
 NBS Technical Notes are designed to supplement the Bu- 
 reau's regular publications program. They provide a 
 means for making available scientific data that are of 
 transient or limited interest. Technical Notes may be 
 listed or referred to in the open literature. 
 
 For sale by the Superintendent of Documents, U.S. Government Printing Office 
 Washington 25, D.C. - Price 15 cents 
 
: 
 
 Contents 
 
 1 . Introduction 1 
 
 2. Discussion 2 
 
 3. Summary. 6 
 
 4. Bibliography 7 
 
 li 
 
COORDINATED COLOR IDENTIFICATIONS FOR INDUSTRY 
 Kenneth L. Kelly 
 
 When a color is to be identified, the preciseness required 
 of the identification is the first consideration. Usually 
 this is determined by a trial-and-error method which can be 
 both costly and time-consuming. For some uses, a color name 
 consisting of a hue name or a hue name and modifier is 
 sufficient while for others, a notation of the color in a 
 color-order system will suffice. Where maximum precision 
 is required, the color should be measured instrumentally 
 and the results expressed numerically. This paper describes 
 the coordinated series of five levels of fineness of color 
 identification developed by ISCC Subcommittee for Problem 23, 
 the Expression of Historical Color Usage, and is based on 
 the ISCC-NBS method of designating colors. It lists the 
 methods for changing from one level to another and gives 
 examples of the use of each level. 
 
 1. Introduction 
 
 There has long been a need in industry and science for a coordi- 
 nated series of different levels of fineness of color designation. Such 
 a series was developed by the Inter-Society Color Council Subcommittee 
 for Problem 23, the Expression of Historical Color .Usage, that is, color 
 trends. This series was mentioned in the report — of that Subcommittee 
 in connection with the necessary statistical analysis, and again in the 
 paper, Some Problems of Color Identification— , given before the Fall 
 Conference of the Building Research Institute incidental to the descrip- 
 tion of other color-order systems. This paper will bring into sharper 
 focus the five levels of fineness of color designation inherent in this 
 series. 
 
 This series is based on the method of color designation developed 
 at the National Bureau of Standards with the cooperation of the Inter- 
 Society Color Council as an answer to the problem of describing the 
 colors of drugs and medicines ,in the National Formulary— and in the , 
 
 United States Pharmacopoeia — . In it the psychological color solid — ' 
 
 was divided into 319 blocks, to each of which was assigned a simple 
 easily understood color name consisting of a hue name, such as red or 
 green, and one or more modifiers to produce designations such as light 
 yellowish brown or pale pink. Since each block is tridimensional, that 
 is, since the color range included in it varies in hue (red, yellow, 
 green), lightness (light, dark), and saturation (vivid, strong, weak), 
 it was necessary to tailor the size and shape of each color-name block 
 so that the color range included would represent the range of color 
 associated by the average person with that color designation. The 
 description of these 319 color-name blocks was " included in the paper, 
 Method of Designating Color — , published in 1939. 
 
In 1946, this ISCC-NBS (Inter-Society Color Council - National 
 Bureau of Standards) method was revised to take account of suggested 
 changes in the color-name boundaries especially with relation to the 
 textile industry. Some hue names were deleted and one added and the 
 number of color names was reduced to 267. The color-name charts de- 
 fining the boundaries of these 267 color-name blocks are contained in 
 National Bureau of Standards Circular 553, the ISCC-NBS Method of Desig- 
 nating Colors and a Dictionary of Color NamesJJL'. The instructions for 
 determining these color names were extended to apply not only to drugs 
 and medicines but rather to any powder, solid, liquid, or microscopic 
 structure without restriction. The modifier weak was replaced with 
 grayish due to the undesirable connotation of the former in such descrip- 
 tions as a weak red brick. 
 
 2. Discussion 
 
 There are many applications in industry and science for which this 
 division of the color solid into 267 parts would be sufficient, but per- 
 haps the most important application of the ISCC-NBS method of designating 
 colors is in serving as the basic structure by which the five levels of 
 fineness of color designation are coordinated. It goes further and con- 
 tains the first three levels. 
 
 For instance, there are nineteen modifiers for the hue range green 
 not including those for yellowish green or bluish green. All of these 
 from greenish white to vivid green can be described as greens; that is, 
 these nineteen color names can be combined or "rolled up" into one hue 
 name. Likewise the ten color names describing yellowish greens can all 
 be described by the hue name yellowish green, and the nine color names 
 describing bluish green colors can be described by the hue name bluish 
 green . Also since yellowish green and bluish green are variations of 
 green they can all be described by the generic hue name green. This then 
 is why the ISCC Subcommittee for Problem 23 called this coordinated 
 series of color-identification systems the color roll-up system, for all 
 the 38 color names describing various greens can first be rolled up into 
 yellowish green, green, or bluish green; and then these three, into the 
 generic hue name green . 
 
 The five levels of fineness of color identification each embrace 
 the whole psychological color solid and are related through the ISCC-NBS 
 method of designating colors. In the first level, the color solid is 
 divided into thirteen parts, ten described by a generic hue name, and 
 three neutrals, white, gray and black. These generic hue names are pink, 
 red, orange, brown, yellow, olive, green, blue, violet and purple. In 
 the second level, the color solid is divided into 29 parts, that is ten 
 of the original 13 parts are further divided and assigned intermediate 
 hue names. These intermediate hue names are yellowish pink, reddish 
 orange, reddish brown, orange yellow, yellowish brown, olive brown, 
 greenish yellow, yellow green, olive green, yellowish green, bluish green, 
 greenish blue, purplish blue, reddish purple, purplish red and purplish 
 pink. In the third level, each part of the color solid described by a 
 generic or intermediate hue name is subdivided and to each such sub- 
 
 2 
 
division is assigned that hue name and the appropriate modifier descrip- 
 tive of its lightness and saturation as shown in the table of modifiers 
 in Circular 553 on page 3. These modifiers include vivid, brilliant, 
 strong, deep, very deep, very light, light, moderate, dark, very dark, 
 very pale, pale, grayish, dark grayish, and blackish. The part of the 
 color solid described by the color name gray, is subdivided into three 
 parts to each of which is assigned a modifier descriptive of its light- 
 ness, light, medium or dark. This is the ISCC-NBS method of designating 
 colors and 'consists of the 267 color-name blocks in Circular 553. 
 
 Level four of our coordinated .series is illustrated by the Munsell 
 Book of Color "? 9 ? 15 ' 18 ' 22 ' 5 ' > 3 ' . There are about 1000 color samples 
 in this book which have been prepared with great care to exemplify equal- 
 ly spaced scales of hue, lightness, and saturation, on which the bound- 
 aries of the ISCC-NBS color-name blocks are based. That is, the Munsell 
 color system is a true color-appearance system and as such lends itself 
 to interpolation and extrapolation among its color samples. So if the 
 desired color is not found among the 1000 samples, its designation may 
 be indicated by specifying its hue to the nearest half hue step out of 
 the 100 hue steps in the Munsell hue circuit, to the nearest one tenth 
 value step (lightness) of the ten value steps between white (Munsell 
 notation 10/) and black (Munsell notation 0/), and to the nearest third 
 chroma step (saturation). The chroma notation of the most saturated 
 color sample in the Munsell Book of Color is /16. Thus the effective 
 number of hues has been increased to 200 by interpolation alone from the 
 40 constant-hue charts of the Munsell Book of Color, a five-fold increase; 
 the number of values has been increased from 10 to 100, and the number 
 of chromas has been multiplied by 6 . It may be said that by inter- 
 polation alone, the effective number of Munsell color samples has been 
 increased by a factor of approximately 5 x 10 x 6 = 300 (or to a total 
 of about 300,000 colors). Also since the boundaries of the ISCC-NBS 
 color-name blocks are specified in terms of the Munsell system, it is 
 easy to determine the ISCC-NBS color name equivalent to any Munsell 
 notation throughout the color solid. 
 
 In level five, the color is measured on a colorimeter or spectro- 
 photometer and the results expressed numeri ra 1 1 y3 , 13 , 32/ ^ e greatest 
 accuracy required in the identification of a color can be realized in this 
 level. The numerical results obtained from a colorimeter or spectro- 
 photometer are usually expressed in chromaticity coordinates (x,y or a,b) 
 and daylight reflectance (Y or R^) and are reliable to two decimal places 
 and sometimes to three. It is hoped that in the not too distant future, 
 through the development of new spectrophotometers coupled with high- 
 speed electronic computers, values of chromaticity coordinates and day- 
 light reflectances obtained spectrophotometrically can be given correct 
 to three decimal places and possibly to four. 
 
 Now let us consider an example whose color can be appropriately 
 described on each of the five levels of fineness of color identification. 
 It is possible that the manufacturer of snow-shovel handles who wanted 
 red, green or blue handles for his product to satisfy his customer's 
 desire for color variety, would be perfectly happy to have nearly any 
 
 3 
 
red, green or blue and would not be too fussy about the tolerances with- 
 in which the handles matched his selected colors. He would thus be 
 using level one. If, however, the green was found to be too yellowish or 
 bluish, he could refine his tolerances by advancing to level two of our 
 coordinated series by stating that he wanted a green handle and not a 
 yellowish green or bluish green one. Suppose now as our manufacturer's 
 knowledge of color increases, and his customers become more sophisticated, 
 he may find through a color survey that he should have specified a vivid 
 red instead of the less expensive uncontrolled red which he had been 
 using. He may have found that vivid red has more eye appeal and further 
 that it contrasts better with snow and green grass. He has thus advanced 
 from level two to level three, that is, to the ISCC-NBS method of desig- 
 nating colors. 
 
 If, however, our industrialist's product is one which must "go 
 with" another colored item, he may well find that this division of the 
 whole color solid into 267 color-name blocks does not give him the color 
 selection which he requires. He must then advance to level four and 
 specify his color in terms of the Munsell color system or an equivalent 
 color-order system. Now let us progress to another industrialist, one 
 who produces refrigerators. He may well sublet the contract for the 
 manufacture of the refrigerator bodies and doors to one manufacturer 
 and that of the plastic cooling-compartment doors to another. Here the 
 tolerances are much more stringent and even an interpolated Munsell no- 
 tation may not suffice. He must then resort to a color measuring instru- 
 ment, a colorimeter or a spectrophotometer. Both of these instruments 
 have advantages and disadvantages and the industrialist must know both or 
 his inspection costs may become too high. Our industrialist has now ad- 
 vanced to level five of our coordinated series of color identification 
 systems. 
 
 From the descriptions of levels four and five, it can be seen that 
 there is a considerable variation of fineness of designation for a color 
 in each of these levels. In level four, for instance, the Munsell Book 
 of Color contains about 1000 color samples, but this figure can be multi- 
 plied by approximately 300 through the use of interpolation alone, while 
 other color-order systems which can also be used in this level contain 
 from 943 to 7056 color samples. In level five, the variation in fineness 
 of color designation is accomplished by increasing the number of decimal 
 places used in the numerical notation. Remember that the number of color 
 designations possible with two decimal places (for each of three coordi- 
 nates) will be increased by a factor of 1000 with three decimal places 
 and by a factor of 1,000,000 with four decimal places. This flexibility 
 is most useful and fortunate in these levels since they will be used more 
 and more in industry and science in the specification of colors and color 
 differences. 
 
 In 1943 there was published at the National Bureau of Standards a 
 paper — including graphs illustrating the chromaticity coordinates and 
 tables listing the daylight reflectances of the 405 color samples in the 
 20-hue edition of the Munsell Book of Color. Also in 1943 theoretical 
 Society of America published the results of an extensive study — of the 
 
Munsell system which attempted through graphs and tables to define an 
 ideal Munsell color system. To distinguish Munsell notations determined 
 through the comparison of a color with the color scales of the Munsell 
 Book of Color, called Munsell book notations, from notations in the ideal 
 Munsell color system, the latter are called Munsell renotations. From 
 either of these sets of graphs, it is possible to convert chromaticity 
 coordinates and daylight reflectances to Munsell book notations or 
 renotations. The latter are usually used. Lately through elegant pro- 
 grams for highspeed computers — , it has been possible to determine in a 
 matter of seconds the Munsell renotation of a color from its chromaticity 
 coordinates and daylight reflectance. 
 
 Now let us summarize the levels of fineness in reverse order. For 
 maximum accuracy, a color should be measured instrumentally and the re- 
 sults expressed numerically or in terms of a Munsell renotation (level 
 five). If this accuracy is not required, a carefully interpolated 
 Munsell book notation may suffice (level four). If one wants a quick 
 understandable color designation such as that of a moist soil sample 
 before its color changes due to drying, a description in terms of the 
 ISCC-NBS color names can be recorded (level three). If one is inter- 
 ested in the color of a thin section of a sample under the microscope 
 where the thickness of the section is not easily controlled, the hue 
 name of the color in question is usually sufficient (level two). Level 
 one is useful when a quick approximate designation of a color is suf- 
 ficient or when color changes or trends are being plotted and where more 
 than thirteen lines on a graph would be confusing. 
 
 It has long been the hope of the National Bureau of Standards and 
 the Inter-Society Color Council that someday color charts could be 
 added to the color-names dictionary with a characteristic color sample 
 illustrating each of the color-name blocks. These most characteristic 
 colors were considered to be those representing the centers of the 
 blocks and thus are called centroid colors. The ISCC-NBS centroid 
 colors were defined at the fi National Bureau of Standards by specifications 
 determined mathematically — in terms of Munsell renotations, some of 
 the centroids being outside the color range of available pigments. 
 Through financial support from the Inter-Society Color Council the pro- 
 totype centroid colors meeting the tolerances prescribed by this Bureau 
 were produced by Davidson and Hemmendinger of Easton, Pa., for 214 of 
 the 267 color-name blocks. Mass produced constant-hue name centroid- 
 color charts are in preparation and will be available through the 
 Standard Materials Program of the National Bureau of Standards, 
 Washington 25, D.C. at about $2.00 per complete set. 
 
 Through the publication of the Munsell notations of part or all of 
 
 :ems 
 
 8TJ2,38 /. 
 
 Manual (third edition, 943 colors— 2 2 ), these color-order systems 
 
 can be used in place of the Munsell Book of Color in level four. Each 
 of these color-order systems has as many as, or more color samples than, 
 the Munsell Book of Color and these samples are arranged systematically 
 
throughout the whole color solid. There are other collections of color 
 samples, smaller than the Munsell Book of Color, whose Munsell notations 
 have been published; these q include the ninth edition of the Standard 
 Color Card (216 colors — 2 ) , produced by the Textile Color Card Associ- 
 ation of the United States (now the Color Association of the United 
 States), the Horticultural Colour Chart (800 colors * 2 ?) , the 256 colors 
 shown in the Nickerson Color Fan— , the 88 colors used by the American 
 Association of Textile Chemists and Co lour is ts-^- , Federal Specification 
 TT-C-595 (first edition, 187 colors- )., the 17 colors for molded urea - 
 and 12 , colors for polystyrene plastics— 5 the~rock colors (115 colors, 
 1951 — ), and the 196 for soil colors (1954—). These smaller collec- 
 tions besides their specific applications, can be used in level three of 
 our coordinated series of color identification systems. In addition to 
 the color samples in the Munsell Book of Color, those in the Color 
 Harmony Manual (third edition) and in the ninth edition of the Standard 
 Color Card have been measured spectrophotometrically and the correspond- 
 ing chromaticity coordinates, daylight reflectances, and Munsell renota- 
 tions have been published. 
 
 To assist in coordinating the color identifications derived from 
 these many collections of color samples, there are listed in the third 
 part of NBS Circular 553, the color names dictionary, all of the color 
 names used in these color-order systems with their equivalent ISCC-NBS 
 color designations. In the second part of NBS Circular 553, all of 
 these color names are listed, each under its equivalent ISCC-NBS color 
 name. Opposite each of these color names in part two, is listed the 
 numerical or letter designation used in each collection to identify the 
 color sample. 
 
 3. Summary 
 
 It was the stated purpose of this paper to describe the method, 
 developed by ISCC Subcommittee for Problem 23, of coordinating the five 
 levels of fineness of color designation. The application of this method 
 to the color problems of industry and science is increasing. The change 
 is slow but sure and the dye man in the shop is finding that the adver- 
 tising man is beginning to understand what he, the dye man, is talking 
 about and vice versa. As the use of this method spreads, men from 
 different industries will find that they have finally a common language 
 for the designation of colors and color differences. One commercial 
 firm is applying this coordinated series to the study of color selection 
 and color trends involving all products that offer the intermediate 
 customer a choice of colors on the manufacturing level as well as the 
 ultimate consumer on the retail level. Through the use of this method 
 it is possible by statistical treatment to correlate marketing data on 
 products whose colors are described in any one of the five levels of 
 fineness of color designation. 
 
4. Bibliography 
 
 American Pharmaceutical Association, The National Formulary 
 (revised every five years). 
 
 American Society for Testing Materials, Committee D-l, Method of 
 specifying color by the Munsell system, ASTM Designation: D1535-58T, 
 issued 1958. 
 
 American Standards Association, Standard Methods of Measuring and 
 Specifying Color, Z58. 7. 1-1951, Z58. 7. 2-1951, and Z58. 7. 3-1951, 
 issued 1951. 
 
 
 The British Colour Council in collaboration with the Royal Horti- 
 cultural Society (London), Horticultural colour chart, 1938 and 
 1940. Copyright Robert F. Wilson. Also issued as the Wilson Colour 
 chart. 
 
 5 Colors for molded urea plastics, Commercial Standard CS147-47, U.S. 
 
 Department of Commerce, 12/15/47. 
 
 6 Colors for polystyrene plastics, Commercial Standard CS156-49, U.S. 
 
 Department of Commerce, 1/1/49. 
 
 7 Federal Specification TT-C-595, Colors; (for) Ready-Mixed Paints. 
 
 Procurable from the Superintendent of Documents, U.S. Government 
 Printing Office, Washington 25, D.C., $4.50. Dated January 12, 1950 
 and issued in 1951. 
 
 8 Granville, W. C, Munsell renotations of Color Harmony Manual chips 
 
 (third edition) from spectrophotometric measurements. Unpublished. 
 Available from Container Corporation of America. 
 
 9 Granville, W.C., Nickerson, D., and Foss, C.E., Trichromatic specifi- 
 
 cations for intermediate and special colors of the Munsell system, 
 J. Opt. Soc. Am. 33, 376-385 (1943). 
 
 10 Hamly, D.H., The Ridgway color standards with a Munsell notation key, 
 
 J. Opt. Soc. Am. 39, 592-599 (1949). 
 
 11 Inter-Society Color Council, Interim Report of the ISCC Subcommittee 
 
 on Problem 23, Expression of historical color usage, Nov. 20, 1960. 
 
 12 Jacobson, E., Color Harmony Manual , Container Corporation of 
 
 America, Chicago, Illinois, 1948, third edition. 
 
 13 Judd, D.B., Color in Business, Science and Industry, John Wiley & 
 
 Sons, Inc., New York, 1952. 
 
 14 Judd, D.B. and Kelly, K.L., Method of designating colors, J. Research 
 
 NBS 23, 355-385 (1939) RP1239. 
 
15 Judd, D.B. and Wyszecki, Gunter, Extension of the Munsell renotation 
 
 system to very dark colors, J. Opt. Soc. Am. 46_, 281-284 (April 
 1956). 
 
 16 Kelly, K.L., Central notations for the revised ISCC-NBS color-name 
 
 blocks, J. Research NBS 61_, 427-431 (Nov. 1958) RP2911. 
 
 17 Kelly, K.L., Some problems of color identification, J. Am. Institute 
 
 of Architects 37,, 80-82 (Mar. 1962). 
 
 18 Kelly, K.L., Gibson, K.S., and Nickerson, D., Tristimulus specifi- 
 
 cation of the Munsell Book of Color from spectrophotometric 
 measurements, J. Research NBS 31, 55 (1943) RP1549; also J. Opt. 
 Soc. Am. 33_, 355-376 (July 1943). 
 
 19 Kelly, K.L. and Judd, D.B., The ISCC-NBS method of designating 
 
 colors and a dictionary of color names, NBS Circular 553, Nov. 1, 
 1955. 
 
 20 Maerz, A. and Paul, M. Rea, A Dictionary of Color, First Edition, 
 
 McGraw-Hill Book Company, Inc., 1930. 
 
 21 Middleton, W.E. Knowles, The Plochere color system; A descriptive 
 
 analysis, Canadian J. Research, F.27, 1-21 (1949); N.R.C. No. 
 1856; also J. Opt. Soc. Am. 39, 633A (1949). 
 
 22 Munsell Color Company, Munsell Book of Color, 1960 edition, Munsell 
 
 Color Company, Inc., 2441 North Calvert Street, Baltimore 18, Md. 
 
 23 Munsell Color Company, Munsell soil color charts, special form for 
 
 use of Soil Scientists, Geologists, and Archaeologists, 1954. 
 Munsell Color Company, Baltimore 18, Md. 
 
 24 National Research Council, Rock-color chart, prepared by the Rock- 
 
 Color Chart Committee (sponsored by 5 geological organizations), 
 Washington, D.C., 1951. 
 
 25 Newhall, S.M., Preliminary report of the OSA subcommittee on the 
 
 spacing of the Munsell colors, J. Opt. Soc. Am. 30, 617-645 (1940). 
 
 26 Newhall, S.M., Nickerson, D., and Judd, D.B., Final report of the 
 
 OSA subcommittee on the spacing of the Munsell Colors, J. Opt. 
 Soc. Am. 33, 385-418 (1943). 
 
 27 Nickerson, Dorothy, Horticultural Colour Chart names with Munsell 
 
 key, J. Opt. Soc. Am. 47, 619-621 (July 1957). 
 
 28 Nickerson, Dorothy, Interrelation of color specifications, Paper 
 
 Trade J. 125, 153 (1947). 
 
29 Nickerson, Dorothy, Modern color science is the background for a 
 
 new and useful color chart for horticulture, Proc. 11th Annual Am. 
 Horticultural Congress and Annual Meeting Am. Horticultural Council, 
 p. 3 - 31, Oct. 1956. 
 
 30 Nickerson, Dorothy, and Newhall, S.M., A psychological color solid, 
 
 J. Opt. Soc. Am. 33, 419-422 (July 1943). 
 
 31 Nickerson, D., Tomaszewski, J. J., and Boyd, T.F., Colorimetric 
 
 specifications of Munsell repaints, J. Opt. Soc. Am. 43, 163-171 
 (1953). 
 
 32 Optical Society of America, Committee on Colorimetry, The Science of 
 
 Color, Thomas Y. Crowell Co., New York, 1953. 
 
 33 Plochere, G. and Plochere, C, Plochere Color System, A guide to 
 
 color and color harmony, Fox Printing Co., Los Angeles, California, 
 1948. 
 
 34 Reimann, G., Judd, D.B., and Keegan, H.J., Spectrophotometric and 
 
 colorimetric determination of the colors of the TCCA standard color 
 cards. J. Research NBS 36, 209-247 (1946) RP1700; also J. Opt. Soc. 
 Am. 36, 128-159 (Mar. 1946). 
 
 35 Rheinboldt, W.C. and Menard, J. P., Mechanized conversion of colori- 
 
 metric data to Munsell renotations, J. Opt. Soc. Am. 50 , 802-807 
 (Aug. 1960). 
 
 36 Ridgway, Robert, Color standards and color nomenclature, Washington, 
 
 D.C., 1912. 
 
 37 The Society of Dyers and Colourists, Colour Index, Bradford, York- 
 
 shire, England, January 1924, Supplement January 1928. 
 
 38 Taylor, Helen D., Knoche, Lucille, and Granville, Walter C, 
 
 Descriptive Color Names Dictionary, Container Corporation of 
 America, Chicago, Illinois, 1950. 
 
 39 Textile Color Card Association of the United States, Inc., Standard 
 
 Color Card of America, 9th Edition, Color Association of the United 
 States, 200 Madison Avenue, New York 16, N.Y., 1941. 
 
 40 United States Pharmacopoeial Convention, The Pharmacopoeia of the 
 
 United States of America (revised every five years). 
 
 41 Webster's Third New International Dictionary, unabridged, G. and C. 
 
 Merriam Co., Springfield 2, Mass., 1961. 
 
 <r U. S. GOVERNMENT PRINTING OFFICE : 1962 O - 666333 
 
U. S. DEPARTMENT OF COMMERCE 
 
 Luther H. Hodges, Secretary 
 
 NATIONAL BUREAU OF STANDARDS 
 A. V. Astin, Director 
 
 THE NATIONAL BUREAU OF STANDARDS 
 
 The scope of activities of the National Bureau of Standards at its major laboratories in Washington, D.C., and 
 Boulder, Colorado, is suggested in the "following listing of the divisions and sections engaged in technical work. 
 In general, each section carries out specialized research, development, and engineering! in the field indicated by 
 its title. A brief description of the activities, and of the resultant publications, appears on the inside of the 
 front cover. 
 
 WASHINGTON, D. C. 
 
 Electricity. Resistance and Reactance. Electrochemistry. Electrical Instruments. Magnetic Measurements 
 Dielectrics. High Voltage. 
 
 Metrology. Photometry and Colorimetry. Refractometry. Photographic Research. Length. Engineering Metrology. 
 Mass and Scale. Volumetry and Densimetry. 
 
 Heat. Temperature Physics. Heat Measurements. Cryogenic Physics. Equation of State. Statistical Physics. 
 Radiation Physics. X-ray. Radioactivity. Radiation Theory. High Energy Radiation. Radiological Equipment. 
 Nucleonic Instrumentation. Neutron Physics. 
 
 Analytical and Inorganic Chemistry. Pure Substances. Spectrochemistry. Solution Chemistry. Standard Refer- 
 ence Materials. Applied Analytical Research, Crystal Chemistry. 
 
 Mechanics. Sound. Pressure and Vacuum. Fluid Mechanics. Engineering Mechanics. Rheology. Combustion 
 Controls. 
 
 Polymers. Macromolecules: Synthesis and Structure. Polymer Chemistry. Polymer Physics. Polymer Charac- 
 terization. Polymer Evaluation and Testing. Applied Polymer Standards and Research. Dental Research. 
 Metallurgy. Engineering Metallurgy. Microscopy and Diffraction. Metal Reactions. Metal Physics. Electrolysis 
 and Metal Deposition. 
 
 Inorganic Solids. Engineering Ceramics. Glass. Solid State Chemistry. Crystal Growth. Physical Properties. 
 Crystallography. 
 
 Building Research. Structural Engineering. Fire Research. Mechanical Systems. Organic Building Materials. 
 Codes and Safety Standards. Heat Transfer. Inorganic Building Materials. Metallic Building Materials. 
 Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Mathematical Physics. Op- 
 erations Research. 
 
 Data Processing Systems. Components and Techniques. Computer Technology. Measurements Automation. 
 Engineering Applications. Systems Analysis. 
 
 Atomic Physics. Spectroscopy. Infrared Spectroscopy. Far Ultraviolet Physics. Solid State Physics. Electron 
 Physics. Atomic Physics. Plasma Spectroscopy. 
 
 Instrumentation. Engineering Electronics. Electron Devices. Electronic Instrumentation. Mechanical Instru- 
 ments. Basic Instrumentation. 
 
 Physical Chemistry. Thermochemistry. Surface Chemistry. Organic Chemistry. Molecular Spectroscopy. Ele- 
 mentary Processes. Mass Spectrometry. Photochemistry and Radiation Chemistry. 
 
 Office of Weights and Measures. 
 
 BOULDER, COLO. 
 
 Cryogenic Engineering Laboratory. Cryogenic Equipment. Cryogenic Processes. Properties of Materials. Cryo- 
 genic Technical Services. 
 
 CENTRAL RADIO PROPAGATION LABORATORY 
 
 Ionosphere Research and Propagation. Low Frequency and Very Low Frequency Research. Ionosphere Re- 
 search. Prediction Services. Sun-Earth Relationships. Field Engineering. Radio Warning Services. Vertical 
 Soundings Research. 
 
 Radio Propagation Engineering. Data Reduction Instrumentation. Radio Noise. Tropo spheric Measurements. 
 Tropospheric Analysis. Propagation-Terrain Effects. Radio-Meteorology. Lower Atmosphere Physics. 
 Radio Systems. Applied Electromagnetic Theory. High Frequency and Very High Frequency Research. Fre- 
 quency Utilization. Modulation Research. Antenna Research. Radiodetermination. 
 
 Upper Atmosphere and Space Physics. Upper Atmosphere and Plasma Physics. High Latitude Ionosphere 
 Physics. Ionosphere and Exosphere Scatter. Airglow and Aurora. Ionospheric Radio Astronomy. 
 
 RADIO STANDARDS LABORATORY 
 
 Radio Physics. Radio Broadcast Service. Radio and Microwave Materials. Atomic Frequency and Time-Interval 
 
 Standards. Radio Plasma. Millimeter-Wave Research. 
 
 Circuit Standards. High Frequency Electrical Standards. High Frequency Calibration Services. High Frequency 
 
 Impedance Standards. Microwave Calibration Services. Microwave Circuit Standards. Low Frequency Calibration 
 
 Services. 
 
NBS