Significance and Use

The ECCs used in the test method will ultimately be exposed (Test Method E2141 ) to solar radiation and deployed to control the amount of radiation by absorption and reflection and thus, limit the solar heat gain and amount of solar radiation that is transmitted into the building.

4.2 The test method referenced herein is a laboratory test conducted under specified conditions. This test method is intended for use in assessing the changes in uniformity of an ECC on vision glass and subjected to a series of tests for assessing the durability of the coating or the IGU unit, or both.

4.3 The useful life of IGUs with an absorptive ECC may depend on their ability to maintain an acceptable uniformity when used in an IGU for buildings applications. As described in Section 1. (See Appendix X1, X1.4 and X1.5), this test method is intended to provide a means for measuring the uniformity of an absorptive electrochromic coating (ECC) on a glazing surface (including when sealed in an insulating glass unit).

Effects of Test Procedures Data generated using this test method may be used to evaluate and compare the effects of subjecting ECCs in IGUs to the accelerated weathering procedures described in Test Methods E2141 , E2240 , or E2241 . This test method requires the measurement of uniformity as a basis for evaluating changes in one of several performance parameters.

Changes in the uniformity of the test specimens may vary from none to significant. Some physical changes in the specimens may be visible when there are no apparent changes in the performance. Similarly, performance changes may occur with no visible changes in the specimens.

All conditions of measurement in this test method must be described in the report so that an assessment of their significance can be made.

Sequencing If this test method is performed as part of a combined sequence with other measurements of the ECC perfomance (see 8.2) and visual inspection (see 8.3 in Test Methods E2141 , E2240 , or E2241 ) determined at the end of one of the test methods, the result may be used as the initial uniformity measurement for the next test; duplication of these uniformity measurements is not necessary unless so specified.

1. Scope

1.1 The test described is a method for measuring the uniformity of an absorptive electrochromic coating (ECC) in a static colored or bleached state on a glazing surface, which is or will be one of two or more glazings in a preassembled permanently sealed insulating glass unit (IGU).

1.2 The test method is applicable only for layered (one or more active coatings between the TCOs) absorptive ECCs on vision glass (superstrate and substrate) areas planned for use in buildings, such as glass doors, windows, skylights, and exterior wall systems. The layers used for electrochromically changing the optical properties may be inorganic or organic materials between the superstrate and substrate and may include laminates.

1.3 The test method is not applicable to other types of coatings on vision glass with other chromogenic coatings that cannot be held in a static colored or bleached state.

1.4 The test method is not applicable to IGUs that will be constructed from superstrate or substrate materials other than glass.

1.5 The test method is not applicable for measuring the uniformity of ECC coatings during the coloring or bleaching processes.

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

1.7 There is no comparable International Standards Organization 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 and health practices and determine the applicability of regulatory requirements prior to use.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

C168 Terminology Relating to Thermal Insulation

C1048 Specification for Heat-Strengthened and Fully Tempered Flat Glass

E2141 Test Methods for Assessing the Durability of Absorptive Electrochromic Coatings on Sealed Insulating Glass Units

E2188 Test Method for Insulating Glass Unit Performance

E2189 Test Method for Testing Resistance to Fogging in Insulating Glass Units

E2190 Specification for Insulating Glass Unit Performance and Evaluation

E2240 Test Method for Assessing the Current-Voltage Cycling Stability at 90C (194F) of Absorptive Electrochromic Coatings on Sealed Insulating Glass Units

E2241 Test Method for Assessing the Current-Voltage Cycling Stability at Room Temperature of Absorptive Electrochromic Coatings on Sealed Insulating Glass Units

Keywords

chromogenic glazing; durability; electrochromic windows; fenestration; insulating glass units; sealed insulating glass units; Chromogenic glazings; Coatings (electrochromic); Electrochromic windows (ECW); Glazing surface; Insulating glass (IG); Sealed insulating glass units; Transparent conducting electrodes ;

ICS Code

ICS Number Code 25.220.40 (Metallic coatings)

DOI: 10.1520/E2355-10

ASTM International is a member of CrossRef.

ASTM E2355