In concealed locations where piping other than cast-iron or galvanized steel is installed through holes or notches in studs, joists, rafters or similar members less than 1 1/2 inches (40 mm) from the nearest edge of the member, the pipe shall be protected by shield plates. Protective shield plates shall be a minimum of 1/16 inches (1.6 mm) thick steel, shall cover the area of the pipe where the member is notched or bored, and shall extend a minimum of 2 inches (50 mm) above sole plates and below top plates.