This laboratory test method can be used on multi-ply roofing and waterproofing systems to measure, classify, and count the voids between felt plies, between insulation layers, and between the membrane and insulation layers. Voids between the felt plies or between the membrane and insulation layer in multi-ply systems can be the seeds for future blisters.

In one-ply systems, this test method can be used to count and measure the voids in the adhesive in laps and, in adhered systems, in the adhesive between the membrane and the insulation. Voids in the lapping adhesive can be the source of leakage while voids in the lapping adhesive or in the adhesive between the membrane and insulation can be the seeds for future blisters.

1.1 This test method includes two procedures for measuring the area of voids in the adhesive between materials used in roofing and waterproofing systems. Both procedures require a count of the number of voids.

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

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.