4.1 In service, vapor retarders may be exposed to a variety of conditions, so no one test will provide evaluations related to performance for all exposures (refer to Guide E241 and Practice C755). Neither will all test methods listed be necessary in all evaluations for specific exposures (see 16.2).

4.2 Limitations—Prior to use and in service, vapor retarders may be exposed to a variety of conditions so no one test will provide evaluations related to performance for all exposures (refer to Guide E241 and Practice C755). Neither will all tests be necessary in all evaluations for specific exposures. Consequently, the tests and required test results shall be agreed upon by the purchaser and the supplier (see 16.2).

1.1 These test methods² cover the determination of the properties of flexible membranes to be used as vapor retarders in contact with earth under concrete slabs, against walls, or as ground cover in crawl spaces. The test methods are applicable primarily to plastic films and other flexible sheets. The materials are not intended to be subjected to sustained hydrostatic pressure. The procedures simulate conditions to which vapor retarders may be subjected prior to and during installation, and in service.

1.2 The test methods included are:

1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.4 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.