W-C-571C, FEDERAL SPECIFICATION: CONDUIT & FITTINGS, NONMETAL, RIGID, (ASBESTOS CEMENT OR FIRE CLAY CEMENT), (FOR ELECTRICAL PURPOSES) (15 JAN 1981)

W-C-571C, FEDERAL SPECIFICATION: CONDUIT & FITTINGS, NONMETAL, RIGID, (ASBESTOS CEMENT OR FIRE CLAY CEMENT), (FOR ELECTRICAL PURPOSES) (15 JAN 1981)., This specification covers conduit, asbestos-cement, or fire-clay cement, and fittings of equivalent material for use in the installation of electrical wires and cables, underground burial.