1.1 This practice covers techniques to accelerate weathering effects of factory-coated embossed hardboard using apparatus described in Practice G 90.

1.2 This practice is based upon Cycle 1 of Practice G 90 (concentrated natural sunlight with periodic surface water spray) plus a soak-freeze-thaw cycle (see 5 of this practice).

1.3 Testing by use of the methods described in this practice may be employed in the qualitative assessment of weathering effects. The relative durability of coated hardboards may be best determined by comparison of their test results with those of pass-fail control specimens derived from real time exposure test experience (see 8.2 for specific guidelines).

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.