Which factor is most critical when measuring potential in Close Interval Potential Surveys?

In Close Interval Potential Surveys (CIPS), the most critical factor when measuring potential is the structure-to-electrolyte potential. This measurement is vital because it reflects how effectively the cathodic protection system is functioning relative to the surrounding electrolyte, which typically includes soil or water.

The structure-to-electrolyte potential indicates the effectiveness of the corrosion mitigation measures employed. By measuring the difference in electrical potential between the protected structure and the surrounding electrolyte, it is possible to determine if sufficient protective current is reaching all areas of the structure. Proper assessment of this potential helps in ensuring that specific zones do not become anodic, leading to corrosion issues.

The other factors, such as temperature, soil composition, and electrolyte quality, can impact measurements but are ultimately secondary to the direct relationship indicated by the structure-to-electrolyte potential itself. Effective cathodic protection requires understanding how well the structure is protected in its immediate environment, which is directly assessed through this measurement.