ASTM C1649-14(2021) - 1.7.2021
Significance and Use

4.1Color measurement quantifies the transmitted color for glass. The user defines an acceptable range of color appropriate for the end use. A typical quality concern for transmittance color measurement of glass products is verification of lot-to-lot color consistency for end-user acceptance.

4.2If the transmitted color of a glass product is consistent from lot-to-lot and within agreed supplier-buyer acceptance criteria, the products color is expected to be consistent and acceptable for end-use.

1. Scope

1.1This practice provides guidelines for the instrumental transmittance measurement of the color of coated and uncoated transparent glass. (See Terminology E284.)

1.2The practice specifically excludes fluorescent and iridescent samples.

1.3The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.4This 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.

1.5This 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.

2. Referenced Documents


Practice for Obtaining Spectrometric Data for Object-Color Evaluation


Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates

CIE 15:2004



Test Method for Transmittance and Color by Spectrophotometry Using Hemispherical Geometry


Guide for Selection of Geometric Conditions for Measurement of Reflection and Transmission Properties of Materials


Practice for Computing the Colors of Objects by Using the CIE System


Terminology of Appearance