4.1 ECDG perform a number of important functions in a building envelope including: reducing the solar energy heat gain; providing a variable visual connection with the outside world; enhancing human comfort (heat gain), security, illumination, and glare control; providing for architectural expression, and (possibly) improving acoustical performance. It is therefore important to understand the relative serviceability of these glazings.

4.2 This test method is intended to provide a means for assessing the relative serviceability of ECDGs, as described in Section 1.

4.3 The test method is intended to simulate in-service use and accelerate aging of the environmentally controlled dynamic glazings.

4.4 Results from these tests cannot be used to predict the performance over time of in-service units unless actual corresponding in-service tests have been conducted and appropriate analyses have been conducted to show how performance can be predicted from the accelerated aging tests.

4.5 The procedure in this test method includes environmental test parameters that are typically used in weatherability tests by standards organizations and are realistic for the intended use of large-area ECDG units.

1.1 This test method covers the accelerated aging and monitoring of the time-dependent performance of environmentally controlled dynamic glazings such as thermochromic (TC) thermotropic, photochromic glazings. and combinations thereof.

1.2 The test method is applicable only for environmentally controlled dynamic glazings. These glazings may be either monolithic glass, monolithic laminated glass, or sealed insulating glass units fabricated for use in buildings, such as exterior doors, windows, skylights, and wall systems.

1.3 During use, the environmentally controlled dynamic glazings tested according to this method are exposed to environmental conditions, including solar radiation and are employed to control the amount of transmitted radiation by absorption and reflection and thus, limit the amount of solar radiation that is transmitted into a building.

1.4 The test method is not applicable to electronically controlled chromogenic devices, such as electrochromic devices.

1.5 The test method is not applicable to environmentally controlled dynamic glazings that are constructed from superstrate or substrate materials other than glass.

1.6 The test method referenced herein is a laboratory test conducted under specified conditions.

1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.8 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.

1.9 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.