1.1 This standard covers the specific procedures and test conditions that are applicable for exposure of unreinforced polyolefin geomembranes to fluorescent UV radiation and condensation. NOTE 1—Polyolefin geomembranes include high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), flexible polyproplyene (fPP), etc.
1.2 Test specimens are exposed to fluorescent UVA 340 lamps under controlled environmental conditions. UVA 340 lamps are standard for this method. NOTE 2—Other types of fluorescent UV lamps, such as UVB-313, can also be used based upon discussion between involved parties. However, if the test is run with another type of fluorescent UV lamps, such as UVB-313, this should be considered as a deviation from the standard and clearly stated in the test report. UVB-313 and UVA-340 fluorescent lamps generate different amounts of radiant power in different wavelength ranges; thus, the photochemical effects caused by these different lamps may vary.
1.3 This method covers the conditions under which the exposure is to be performed and the test methods for evaluating the effects of fluorescent UV, heat and moisture in the form of condensation on geomembranes. General guidance is given in Practices G151 and G154.
1.4 The values listed in SI units are to be regarded as the standard.
1.5 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 limitations prior to use.
1.6 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.
ASTM D7238-06(2017) Referenced Document
ASTM D1238 Standard Test Method for Flow Rates of Thermoplastics by Extrusion Plastometer
ASTM D5885 Standard Test Method for Oxidative Induction Time of Polyolefin Geosynthetics by High-Pressure Differential Scanning Calorimetry
ASTM D6693 Standard Test Method for Determining Tensile Properties of Nonreinforced Polyethylene and Nonreinforced Flexible Polypropylene Geomembranes*, 2024-04-21 Update
ASTM G113 Standard Terminology Relating to Natural and Artificial Weathering Tests of Nonmetallic Materials
ASTM G151 Standard Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light Sources
ASTM G154 Standard Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Materials*, 2023-01-01 Update
ASTM G156 Standard Practice for Selecting and Characterizing Weathering Reference Materials Used to Monitor Consistency of Conditions in an Exposure Test
ASTM D7238-06(2017) history
2020ASTM D7238-20 Standard Test Method for Effect of Exposure of Unreinforced Polyolefin Geomembrane Using Fluorescent UV Condensation Apparatus
2017ASTM D7238-06(2017) Standard Test Method for Effect of Exposure of Unreinforced Polyolefin Geomembrane Using Fluorescent UV Condensation Apparatus
2006ASTM D7238-06(2012) Standard Test Method for Effect of Exposure of Unreinforced Polyolefin Geomembrane Using Fluorescent UV Condensation Apparatus
2006ASTM D7238-06 Standard Test Method for Effect of Exposure of Unreinforced Polyolefin Geomembrane Using Fluorescent UV Condensation Apparatus