This standard is to be used in conjunction with NACE Standards RP-01-69 "Control of External Corrosion on Underground or Submerged Metallic Piping Systems (latest revision)," RP-06-75 "Control of Corrosion on Offshore Steel Pipelines," and RP-01-77 "Mitigation of Alternating Current and Lightning Effects on Metallic Structures and Corrosion Control Systems (latest revision)." In each of these standards, reference is  made to "electrical isolation" or "isolation joints," but details are not provided. This standard was prepared to supplement those standards, giving ffull details of the  requirements necessary to ensure adequate isolation of cathodically protected pipelines. It must be emphasized that pipeline corrosion control by cathodic protection may be ineffective or impossible if the necessary isolation is not provided. Electrical isolation is of particular importance where cathodic protection is to be applied to a pipeline with a high quality dielectric coating.

This standard does not discuss situations in which isolating devices are incorporated purely for safety reasons. In these situations, reference should be made to the relevant electrical safety code.

This standard was prepared by Task Group T-10A-15 on Electrical Isolation of Cathodically Protected Pipelines, a component of Unit Committee T-10A on Cathodic Protection, and is issued by NACE under the auspices of Group Committee T-10 on Underground Corrosion Control. The T-10A-15 Task Group was initiated by the UK Corrosion Control Engineering Joint Venture (CCEJV), a joint venture between NACE and the Institution of Corrosion Science and Technology (Birmingham, England).

Historical Document 1986