ASTM D7133-21

1.1''This test method provides an instrumental method for measuring the CIELAB color and Yellowness Index (YI) of liquid polyurethane raw materials. The CIELAB and YI results are derived from mathematical manipulation of CIE tristimulus values in accordance with Practices E308 and E313, respectively.

1.2''The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions provided for information only and are not considered standard.

1.3''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.

1.4''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.