1.1 ,This specification covers flexible chlorinated polyethylene (CPE) sheeting which is used without mastic, bedding, or coating for construction of concealed water-containment membranes in applications where there is potential for costly secondary damage from leakage, and where very long-term reliable performance is essential. Examples are fountains, pools, planters, shower and safe pans, tile tubs, and similar installations where the membrane is inaccessible once construction is complete. Included are requirements for composition, strength and toughness, test methods, workmanship criteria, and methods of marking.