1.1 This specification covers rubber rings used to seal the joints of asbestos-cement pipe conforming to Specifications C296, C428, C644, and C668.

1.2 A specification is given for (1) natural or synthetic rubber rings, or both, where resistance to oil or solvents is not required, and (2) synthetic rubber rings for services involving resistance to oil or solvents.

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

1.4 The following safety hazards caveat pertains only to the test methods portion, Section 8, of this standard: 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.