1.1 This practice is intended to provide guidance to architects, specifiers, manufacturers, and other parties who have an interest in evaluating the service life of chromogenic glazings.

1.2 This practice is intended to cover the main factors about service life that must be considered when evaluating glazings for performance until the failure time is reached. However, users of this practice must be aware that other factors must be considered, such as the effect of the interaction of materials, the use of the glazings, and to the environment in which a chromogenic glazing is exposed over its service life.

1.3 The test methods referenced herein are laboratory tests conducted under specified conditions. These test methods are intended to simulate and, in some cases, to also accelerate actual in-service use of the chromogenic glazings. Results from these test methods cannot be used to predict the performance with time of units in the field unless actual corresponding field tests have been conducted and appropriate analyses have been conducted to show performance can be predicted from accelerated aging test methods.