1.1 This specification covers requirements and test methods for the characterization of polyamide 12 pipe, tubing, and fittings for use in fuel gas mains and services for direct burial and reliner applications. The pipe and fittings covere This specification details the material and performance requirements, as well as the corresponding test methods, for the evaluation of polyamide 12 gas pressure pipes, tubing, and fittings that are intended for use in the distribution of natural gas in