ASTM E1348-22

SIGNIFICANCE AND USE 5.1 The most direct and accessible methods for obtaining the color coordinates of object colors are by instrumental measurement using spectrophotometers or colorimeters with either hemispherical or bidirectional optical measuring systems. This test method provides procedures for such measurement by transmittance spectrophotometry using a hemispherical optical measuring system. 5.2 This test method is especially suitable for measurement of the following types of specimens (see also Guide E179 and Practice E805): 5.2.1 Fully transparent specimens (free from turbidity, haze, or translucency), and 5.2.2 Translucent or hazy specimens, provided that the specimen can be placed flush against the transmission port of the integrating sphere. 5.3 This test method is not recommended for measurement of retroreflective transparent or translucent specimens, or samples that are fluorescent. SCOPE 1.1 This test method describes the instrumental measurement of the transmission properties and color of object-color specimens by the use of a spectrophotometer or spectrocolorimeter with a hemispherical optical measuring system, such as an integrating sphere. 1.2 This test method is generally suitable for all fully transparent specimens without regard for the specimen position relative to the transmission port of the instrument. Translucent specimens, however, must be placed flush against the transmission port of the sphere. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 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. 1.5 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.