Which organization sets the standard specifications for pipe materials used inside buildings?

The American Society for Testing Materials (ASTM) is the organization that sets the standard specifications for pipe materials used inside buildings. ASTM develops and publishes voluntary consensus technical standards for materials, products, systems, and services, which are widely recognized and adopted by various industries, including plumbing and construction. These standards ensure that the materials used meet specific safety, performance, and quality criteria, providing guidance for manufacturers and installers to guarantee the reliability and durability of pipe systems within structures.

In contrast, while the American Water Works Association (AWWA) focuses more on standards relating to water supply operations and infrastructure, as well as the treatment and distribution of water, its standards are not specifically tailored for building interiors. The Philippine Standard Council (PSC) develops national standards but does not focus on the specific technical specifications for materials used in construction like those set forth by ASTM. Similarly, Underwriters Laboratories (UL) specializes in safety testing and certification of products, but it does not create standards solely for the materials used in piping systems. Thus, ASTM is the correct choice for setting standards specifically related to pipe materials used inside buildings.