ASTM D2126-20

4.1?Because of the wide variety of potential uses of rigid cellular plastics, artificial exposure to estimate the effective behavior of these materials must be based, to a great extent, on the intended application. Toward this end, this test method is intended to recommend a variety of conditions from which one or more of the desired exposure conditions can be selected. (Note 3)

4.2?The conditions recommended in this test method have been widely used in artificially exposing rigid cellular plastics and in determining the effects of various temperatures and humidities on these materials. Final test measurements are determined after the specimens return to room temperature. Where specified, the specimens will be tested at the exposure condition, but must be reported as such.

4.3?Dimensional changes measured by this test method can be used to compare the performance of materials in a particular environment, to assess the relative stability of two or more cellular plastics, or to specify an acceptance criterion for a particular material. The results of this test method are not suitable for predicting end-use product performance or characteristics, nor are they adequate for engineering or design calculations.

4.4?Before proceeding with this test method, reference shall be made to the specification of the material being tested. Any test specimen preparation, conditioning, dimensions, or testing parameters covered in the materials specification, or combination thereof, shall take precedence over those mentioned in this test method. If there are no specifications, then the default conditions apply.

1.1?This test method covers procedures for the thermal and humid exposure of rigid cellular plastics. Conditions used shall be agreed upon between the purchaser and the supplier.

1.2?The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.

1.3?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.

1.4?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.