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. Designation: G154 - 23 INTERNATIONAL Standard Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Materials1 This standard is issued under the fixed designation G154; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. 1. Scope* 1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 1.1 This practice is limited to the basic principles for standard. operating a fluorescent UV lamp and water apparatus; on its own, it does not deliver a specific result. 1.7 This standard is technically similar to ISO 4892-3 and 1.2 It is intended to be used in conjunction with a practice or ISO16474-3. method that defines specific exposure conditions for an appli- 1.8 This standard does not purport to address all of the safetyconcerns,if any,associated with its use.Itisthe cationalongwithameanstoevaluatechangesinmaterial responsibility of the user of this standard to establish appro- properties. This practice is intended to reproduce the weather- ing effects that occur when materials are exposed to sunlight priate safety, health, and environmental practices and deter- mine the applicability of regulatory limitations prior to use. (eitherdirectorthroughwindowglass)andmoistureasrainor dew in actual usage. This practice is limited to the procedures 1.9 This international standard was developed in accor dance with internationally recognized principles on standard- for obtaining, measuring, and controlling conditions of expo- ization established in the Decision on Principles for the sure. Development of International Standards, Guides and Recom- NoTE 1-Practice G151 describes general procedures to be used when mendations issued by the World Trade Organization Technical exposing nonmetallic materials in accelerated test devicesthat use Barriers to Trade (TBT) Committee. laboratory light sources. Nore 2—A number of exposure procedures are listed in an appendix; 2. Referenced Documents however, this practice does not specify the exposure conditions best suited for the material to be tested. 2.1 ASTM Standards:2 D5870 Practice for Calculating Property Retention Index of 1.3 Test specimens are exposed to fluorescent UV light Plastics under controlled environmental conditions. Different types of D6631 Guide for Committee D01 for Conducting an Inter- fluorescent UV lamp sources are described. laboratory Study for the Purpose of Determining the Nore 3-In this standard, the terms UV light and UV radiation are used Precision of a Test Method interchangeably G113 Terminology Relating to Natural and Artificial Weath- 1.4 Specimen preparation and evaluation of the results are ering Tests of Nonmetallic Materials covered in ASTM methods or specifications for specific G151PracticeforExposingNonmetallicMaterialsinAccel- materials. General guidance is given in Practice G151 and erated Test Devices that Use Laboratory Light Sources ISO 4892-1. G177 Tables for Reference Solar Ultraviolet Spectral Distri- butions: Hemispherical on 37 Tilted Surface NorE 4General information about methods fordetermining the 2.2ISO Standards:3 change in properties after exposure and reporting these results is described ISO 4582 Plastics—Determination of the Changes of Colour inISO4582andPracticeD5870. and Variations in Properties After Exposure to Daylight 1.5 This practice is not intended for corrosion testing of bare Under Glass, Natura