1.1 ,This specification covers axially unrestrained bell-and-spigot gasket joints including couplings required for machine-made “,fiberglass”, (glass-fiber-reinforced thermosetting-resin) pipe systems, 8 in. (200 mm) through 156 in. (4000 mm), using flexible elastomeric seals to obtain soundness. The pipe systems may be pressure (typically up to 250 psi) or nonpressure systems for water or for chemicals or gases that are not deleterious to the materials specified in this specification. This specification covers materials, dimensions, test requirements, and methods of test.