Principles and issues in structural health monitoring using corrosion sensors

© 2017 by NACE International. Structural health monitoring using corrosion sensors (or probes) is a practical approach to enhancing the safety and economic operation of industrial and civil infrastructures such as oil and gas pipelines, chemical and petrochemical plants, bridges and aircrafts. If used properly, corrosion sensors can provide in-situ and site-specific corrosion information for the early warning of structural failure and for infrastructural life prediction. Over the past decades variously designed corrosion sensors have been developed; however principles and issues associated with the practical application of corrosion sensors have not yet been carefully examined. Corrosion sensors are often treated as a normal measurement device like a thermometer; consequently successful application of corrosion monitoring in complex systems such as buried oil and gas pipelines has been limited. This paper presents some considerations on principles and issues affecting the reliability and trustworthiness of corrosion sensors. Fundamental aspects in the design and application of corrosion sensors, as well as challenges that may lead to the reporting of inaccurate or misleading corrosion data, has been discussed and illustrated by the case of under-deposit corrosion monitoring using a multi-electrode array.