My mistake

When watching sport on television, it is relatively easy to spot errors made by the participants. To assist the viewer, there are any number of pundits queueing up to analyse what the sportsperson did wrong and stating what they should have done instead. The benefit of hindsight does not seem to prevent the errors being repeated, however. This is not due to any lack of desire to achieve a flawless performance, but stems from the mere fact that we are all human. The errors that creep into sports performance, as in other areas of life, have physical and mental triggers. The application of fine motor skills is impacted by fatigue as well as psychological factors. Fatigue also degrades decision-making, leading to poor outcomes. Time pressures and other sources of stress impact both physical and mental activities.

Moving away from competitive sport, errors in communication were highlighted during a television programme about the manufacture of a bespoke product. While these may have been contrived for ‘artistic’ effect, they did emphasise the need for the sender to ensure that their requirements have been received and clearly understood and for the listener to ask for clarification if they think there is a mistake in what they have been told. Technology can also be a source of errors. Everyone will know of instances when over-reliance on a sat nav has resulted in poor outcomes for the driver. I nearly fell foul of the opposite, when the direction from the sat nav conflicted with the general direction I believed I should be going in. Luckily, I went with the former and avoided an unnecessary diversion. Not something to be taken lightly with the current cost of 

After discussing topics for my articles with a family member, I was sent a copy of The Great Outdoors, March 2022 issue. This contained a whole article on mistakes that had been made when out on the hills and the subsequent lessons learned by the individuals who shared their experiences. The article is well worth a read, especially if you participate in hill walking. In summary, the lessons focus on having the correct gear, proper planning, allowing sufficient time and avoiding complacency. Connected to the latter is the statement that, irrespective of experience, the plainly obvious can still be overlooked. The editorial introducing the article points out that most fatal mountain accidents involve experienced hill walkers and hikers.

All of the above is relevant to the application of NDT even though, thankfully, we do not have television pundits to analyse and distil our mistakes and errors for dissemination to the wider community. NDT is a vigilance activity and so fatigue and stress contribute to the increased probability of mistakes. As the final activity in the manufacturing process, and owing to the commercial urgency to get a plant back online and operating again following in-service inspections, manufacturing and in-service NDT are subject to time pressures. 

The decision-making process operators must apply is generally well defined in the inspection procedure. This includes the final sentencing decision: if the indication is greater than X – reject; if less than X – accept. This mitigates against the prevalence of errors in decision-making while fatigued; however, it is predicated on the procedure writer knowing the types of defect signal that are likely to be generated. Occasionally, unexpected defects are present and then 
the decision is thrown back onto the skills and experience of the operator. Defect indications, especially those observed with advanced NDT techniques, do not always lend themselves to a ‘go/no go’ approach. In deciding if the indication is reportable or not, knowledge of the consequences of the decision can loom large.

There are a number of standard error traps within various industries to ensure health and safety and prevent mistakes in the workplace. These can be equally applied to NDT activities. For example, the use of a reverse brief can avoid the miscommunication described higher up. More specific to NDT are the reliability actions I mentioned last month and, hopefully, the ideas you jotted down in the space that was provided. There are two final relevant outputs from the hill walking lessons. Advanced gear alone is not sufficient. The knowledge, skills and experience to use it correctly are also 
needed and an existing process may need to be tailored to suit. Mistakes and errors will occur, but it is the subsequent actions taken that prevent more serious consequences. NDT is well positioned on training and experience requirements, but there are improvements to be made in learning from 

It is worth remembering that the raison d’être of NDT is to check for errors in the design, manufacture and operation of a component or a piece of 
plant equipment.

Please note that the views expressed in this column are the author’s own personal ramblings for the purpose of encouraging discussion within NDT News. They do not represent the views of Jacobs 

Letters can be mailed to The Editor, NDT News, Midsummer House, Riverside Way, Bedford Road, Northampton NN1 5NX, UK. Fax: +44 (0)1604 438301; Email: or email Bernard McGrath direct at

Comments by members

This forum post has no comments, be the first to leave a comment.

Submit your comment

You need to log in to submit a Comment. Please click here to log in or register.

<< Back