This standard describes the requirements for the materials and application of a cement–mortar lining to the inside surface of 4-in. (100-mm) and larger new and old steel, ductile-iron, and cast-iron water pipelines that have been previously installed, as well as related work. The application requirements are that the lining of straight pipe sections and long-radius bends shall be performed by a machine that progresses uniformly through the pipe, applies cement mortar against the pipe surfaces, and is provided with an attachment for mechanically troweling the mortar to obtain a smooth lining of uniform thickness with smooth transitions over joints, and that the lining of bends, specials, and areas adjacent to valves shall be machine sprayed and hand troweled or, where machine placement is impractical, shall be performed manually. It can be referenced in documents for cement–mortar lining of water pipelines in place, 4 in. (100 mm) and larger.