ASTM D 7990:2021

1.1 This test method uses reflectance spectra from the ultraviolet, visible, and near infrared region to produce an index of the temperature rise of polymeric siding above ambient temperature that occurs due to absorption of the suns energy. 1.2 The test method determines the intensity factor of a sample color. The intensity factor is a function of the samples reflectance spectra and the energy output of the heat lamp used in the test method Test Method D4803 . 1.3 Appendix X1 provides a method for using the intensity factor to determine the maximum temperature rise of a sample under severe solar exposure. 1.3.1 A correlation between intensity factor and heat buildup (temperature rise) as predicted by Test Method D4803 exists. 1.3.2 The heat buildup (temperature rise) for a polymeric building product specimen is determined from its reflectance spectra and the correlations regression equation. 1.4 Units The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 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. 1.6 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.

83.140.99, 91.060.10