1.1 This specification covers asphalt-saturated organic felt for use as an underlayment with steep slope roofing.

1.2 The values stated in SI units are to be regarded as the standard.

1.3 The objective of this standard is to provide a finished product that will lie flat and resist wrinkling, puckering, and shrinking when left exposed to the sun, rain, frost, or dew for a period of two weeks after application.

1.4 The following safety hazards caveat pertains only to the test method portion, Section 8, of this specification: This standard does not purport to address all of the safety problems, 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.