Book Review: “Under Pressure – Diving Deeper with Human Factors” by Gareth Lock


We generally have one common goal in all our dive plans – getting back out of the water healthy and happy. But other goals can be important too! On a recent photogrammetry exercise, my scuba kit was checked and in good order, but I got into the water with a vacuum-sealed housing containing no camera – that dive could have been a disappointing waste of time, however safely conducted.

When things go wrong in diving it’s normal to identify a critical error and seek to identify – and blame – the individual responsible. This tendency can lead to a group’s collective actions and biases, in the lead-up to a particular failure, being ignored in the analysis. This hinders us in learning useful lessons and developing safer behaviours. In my case I have now written a “Stills Camera” checklist as well as one for “OC Scuba”; this should help prevent that ever happening again.

I make this embarrassing confession in the spirit of openness which Gareth Lock advocates in his important new book “Under Pressure – Diving Deeper with Human Factors”. This brings together years of work to examine the numerous non-technical skills which are required for successful activities in high-risk environments (specifically, underwater).

A “Just Culture” which promotes, rather than punishes, the sharing of experience is to all our benefit. Gareth has solicited a number of accounts of accidents, near-misses and bad situations from respected and experienced divers. These illustrate clearly the different ways in which human behaviours can lead to things going wrong, or to minor problems being compounded when they should have been handled. More importantly he introduces a number of tools and proposes an approach to the organisation of diving activities which enables all the participants to contribute to the safe execution of the dives and to perform as safely as possible.

This is a thought-provoking, absorbing and educational read which is relevant to any diver. I will certainly refer back to it and expect to read it again!

For more information about the book and Gareth himself visit

Alex Tasker

Alex Tasker

Alex was a hardy teenager when he first dived in the North Sea in a borrowed wetsuit but only really got into diving with his partner in 2009. They’ve ticked off a few bucket-list destinations but remain enthusiastic about all that UK diving has to offer. Alex only learned to use a camera properly since taking one underwater and now rarely dives without it. He’s recently expanded his interest in photographing shipwrecks into some experiments with photogrammetry, with ambitions to produce some archaeologically useful models.

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