ASTM D1535-14(2018)

4.1 This practice is used by artists, designers, scientists, engineers, and government regulators, to specify an existing or desired color. It is used in the natural sciences to record the colors of specimens, or identify specimens, such as human complexion, flowers, foliage, soils, and minerals. It is used to specify colors for commerce and for control of color-production processes, when instrumental color measurement is not economical. The Munsell system is widely used for color tolerancing, even when instrumentation is employed (see Practice D3134). It is common practice to have color chips made to illustrate an aim color and the just tolerable deviations from that color in hue, value, and chroma, such a set of chips being called a Color Tolerance Set. A color tolerance set exhibits the aim color and color tolerances so that everyone involved in the selection, production, and acceptance of the color can directly perceive the intent of the specification, before bidding to supply the color or starting production. A color tolerance set may be measured to establish instrumental tolerances. Without extensive experience, it may be impossible to visualize the meaning of numbers resulting from color measurement, but by this practice, the numbers can be translated to the Munsell color-order system, which is exemplified by colored chips for visual examination. This color-order system is the basis of the ISCC-NBS Method of Designating Colors and a Dictionary of Color Names, as well as the Universal Color Language, which associates color names, in the English language, with Munsell notations (3).

1.1 This practice provides a means of specifying the colors of objects in terms of the Munsell color order system, a system based on the color-perception attributes hue, lightness, and chroma. The practice is limited to opaque objects, such as painted surfaces viewed in daylight by an observer having normal color vision. This practice provides a simple visual method as an alternative to the more precise and more complex method based on spectrophotometry and the CIE system (see Practices E308 and E1164). Provision is made for conversion of CIE data to Munsell notation.

1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.