1.1 This practice covers the exposure of plastics to a specific test environment. The test environment is an externally-heated laboratory-scale reactor that simulates a composting system. Plastic exposure occurs in the presence of a media undergoing aerobic composting. The standard media simulates a municipal solid waste from which inert materials have been removed. This practice allows for the use of other media to represent particular waste streams. This practice provides exposed specimens for further testing and for comparison with controls. This test environment does not necessarily reproduce conditions that could occur in a particular full-scale composting process. 1.2 Changes in the material properties of the plastic and controls should be determined using appropriate ASTM test procedures. Changes could encompass physical and chemical changes such as disintegration and degradation. 1.3 This practice may be used for different purposes. Therefore, the interested parties must select: exposure conditions from those allowed by this practice; criteria for a valid exposure, that is, minimum or maximum change requirements for the compost and controls; and the magnitudes of material properties changes required for the plastic specimens. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 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. Specific hazard statements are given in Section 8. Note-There is no similar or equivalent ISO standard.