1.1 This recommended practice presents accepted procedures for applying impressed current cathodic protection to the internal submerged surfaces of steel tanks used for the storage of natural waters.

The information is presented under the following headings:

Section 2: Definitions

Section 3: Determination of Need for Cathodic Protection

Section 4: Design of Impressed Current Cathodic Protection Systems

Section 5: Installation of Cathodic Protection Systems

Section 6: Criteria for Cathodic Protection

Section 7: Automatic Impressed Current Systems

Section 8: Operation and Maintenance

This NACE recommended practice, prepared by Task Group T-7L-1 of Unit Committee T-7L on Cathodic Protection in Natural Waters, is issued under the auspices of Group Committee T-7 on Corrosion by Waters. The task group is composed of corrosion engineers and others experienced in the design, installation, and maintenance of cathodic protection systems for water storage tanks. The purpose of this recommended practice is to present the procedures and practices used in providing impressed current cathodic protection to the normally submerged steel surfaces inside these tanks. It contains recommendations for the design and installation of cathodic protection systems and methods for determining the effectiveness of these systems. Recommendations for the operation and maintenance of both automatic and manual systems are also provided. This recommended practice is applicable.to impressed current cathodic protection systems for relatively large water storage tanks used in municipal water supply and fire protection. These systems include elevated water storage tanks as well as flat-bottom ground storage tanks. Although the general principles outlined in this standard are applicable IQ all tanks, the impressed current type cathodic protection system described in this standard may not be practical for smaller tanks.

This standard was reaffirmed without revisions_ in April 1990.

Historical Document 1990