This standard covers cathodic protection systems intended to minimize corrosion of submerged interior steel surfaces of water storage tanks and 30-in. (750 mm) diameter and larger wet risers of elevated tanks. This standard does not cover sacrificial (galvanic) anode-type cathodic protection systems or manually controlled, impressed-current systems. The purpose of this standard is to provide purchasers, manufacturers, and suppliers with the minimum requirements for automatically controlled, impressed-current cathodic protection for the interior of steel water tanks, including design, system components, and workmanship and installation.