1.1 These test methods cover the determination of the strength properties of prefabricated architectural acoustical tile or lay-in ceiling panels as follows:

Tests Sections Hardness 2 to 7 Friability 8 to 13 Sag 14 to 20 Transverse strength 21 to 26

1.2 Not all of the tests described in these test methods may be necessary to evaluate any particular product for a specific use. In each instance, it will be necessary to determine which properties are required.

1.3 These test methods specify procedures that may be used in product development, manufacturing control, specification acceptance, and service evaluation.

1.4 Properties determined by these test methods reflect the performance of the materials under the specific conditions of the test, and do not necessarily indicate performance under conditions other than those specified herein.

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.