ASTM G 154:2023

1.1 This practice is limited to the basic principles for operating a fluorescent UV lamp and water apparatus; on its own, it does not deliver a specific result. 1.2 It is intended to be used in conjunction with a practice or method that defines specific exposure conditions for an application along with a means to evaluate changes in material properties. This practice is intended to reproduce the weathering effects that occur when materials are exposed to sunlight (either direct or through window glass) and moisture as rain or dew in actual usage. This practice is limited to the procedures for obtaining, measuring, and controlling conditions of exposure. Note 1: Practice G151 describes general procedures to be used when exposing nonmetallic materials in accelerated test devices that use laboratory light sources. Note 2: A number of exposure procedures are listed in an appendix; however, this practice does not specify the exposure conditions best suited for the material to be tested. 1.3 Test specimens are exposed to fluorescent UV light under controlled environmental conditions. Different types of fluorescent UV lamp sources are described. Note 3: In this standard, the terms UV light and UV radiation are used interchangeably. 1.4 Specimen preparation and evaluation of the results are covered in ASTM methods or specifications for specific materials. General guidance is given in Practice G151 and ISO 4892-1. Note 4: General information about methods for determining the change in properties after exposure and reporting these results is described in ISO 4582 and Practice D5870 . 1.5 This practice is not intended for corrosion testing of bare metals. 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 This standard is technically similar to ISO 4892-3 and ISO 16474-3. 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.

19.040