Foil in thickness of about 0.002 in. (0.05 mm) and heavier is virtually free of pinholes. With decrease in thickness, the number of pinholes may increase.

This method is provided to develop and maintain uniformity in the methods of evaluating pinholes in aluminum foil. The pinhole data provides assessments of process capability and quality levels of the foil as well.

1.1 This method covers the identification and counting of pinholes, including roll holes, in plain foil using a light table, and inspector with normal 20/20 or corrected 20/20 vision, and a darkened inspection area.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This method may involve hazardous materials, operations, and equipment. 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.