Earthing Design Accuracy, Precision, Quality and Safety, a Discussion of the Interrelationship of Each

Quality is generally transparent when present, but easily recognised in its absence”, Alan Gillies said this in his book about software quality. It’s valid for deliverables across a large number of industries and disciplines. Gauging the quality attributes inherent in aspects of the physical implementation of an earthing system is relatively easy in most cases, even those with no understanding of electrical systems can see the experience and craft used in the installation of the earth bar and associated cabling.

Assessing the quality of a less tangible deliverable like an earthing design is not as straightforward. Given that earthing is commonly regarded as a mystery even by engineers, those that purchase and use earthing designs are often ill-equipped to evaluate the intrinsic quality of the outcomes they have paid for. And what have they paid for? They are issued documentation which details implementation requirements or strategies and expected outcomes. But they paid for (and were sold) a much more fundamental product. They pay for an appropriately qualified entity (an expert) to provide a reduction in their exposure to risk and liability. To help demonstrate appropriate due diligence, to provide peace of mind. In lieu of engaging more specialists, how is the effectiveness of an earthing design or assessment at reducing liability determined? How is the quality of the deliverable measured?

Often judgements are made on aspects of the documentation as the only tangible artefact. Document appearance, spelling, detail, and content, and so on are all obvious quality characteristics and in conjunction with the manner in which key engineering outcomes are expressed, provides a sense of the proficiency of the practitioner – and by extension the overall quality. Further, comparisons made to similar documents from providers in other fields, where precision and accuracy of outcomes is paramount, tend to direct the expectations for the key parameters for earthing design also. This is further fostered by the tools utilised by the earthing industry.

This presentation is a discussion on the role that accuracy and precision plays in earthing designs and assessments, the problems associated with utilising precision and accuracy as quality indicators for earthing design, where and when precision is warranted or required, and how any of this can be associated with safety and risk, and the clients overriding aspiration for the re-assignment of risk and liability.