NBN EN 13509:2003

This European Standard deals with the cathodic protection against corrosion of buried or immersed metallic structures, detailing the measuring methods to be used for assessing the effectiveness of cathodic protection as well as the measurements and measures taken to monitor cathodic protection during operation.

Throughout the text, the measurement techniques are described primarily for pipelines.
However, they are sufficiently general to apply to other kinds of buried or immersed (except offshore) structures.

General principles with regard to cathodic protection are described in EN 12954. Other measurement methods specific to particular cases are described in other European Standards e.g. prEN 50162.