Standards Development

Scope

This Technical Specification describes the way of making Electrochemical Noise Measurements (ENM), specifically focusing on its use for assessment of the protection being afforded by organic coatings to metal substrates. It outlines the procedure for use of the electrochemical apparatus, experimental set up and electrodes configurations, the presentation of measured data, and analysis of results. A detailed description of the methodology for application to bare metal, can be found in ISO 17093 (prepared by ISO TC 156 WG 11).

Purpose

Although other electrochemical methods are available, no method is as suitable for site/field use as ENM. Several countries (UK, USA, Australia, Holland, Spain, Argentina, Czech republic and Belgium) are using this method in the laboratory to monitor and assess anti corrosive organic coatings. This is therefore a rapidly growing field with many published examples in the research literature, as well as a comprehensive review (Progress in Organic Coatings, 95, June 2016, pp 26-37). Recent developments have been made in the methodology, including a portable electrochemical noise measuring device (PECN) which is greatly enhancing the application of this technique.

The Technical Specification will be used in conjunction with a standard (ISO 17093 Corrosion of Metals and alloys-guidelines for corrosion tests by electrochemical noise measurements). The latter covers use of electrochemical noise generally in order to measure corrosion rate/detect pitting of bare metals. Having available a TS for application to organically coated metal.as an addenda to the standard would greatly widen its use into the commercial sector. ENM is a technique which has the potential to be used in the field. It would enable asset managers to condition-monitor their coated metal structures and assist them to make decision as to whether repainting is required, thereby avoiding damage or, in extreme case, loss of the asset. Also it can be used as quality control test by applicators to see if the coating system is protective. The need for this TR relates to the recent revision by TC35 SC9 WG 29 of the EIS standard (ISO 16773) to include bare metal. But to properly make EIS measurements on bare metal ISO 16773 has to be used in conjunction with TR 16208. So this new TR is needed to parallel that document and be complimentary to ISO 17093.