Counter-Errorism in Diving: Applying Human Factors to Diving

In this episode, Gareth Lock reflects on why improving diving safety requires more than telling people to follow the rules. Drawing on his experience in aviation, diving, and safety science, he explains why incidents are often blamed on individuals while the wider system escapes scrutiny. The discussion explores how culture, reporting systems, commercial pressures, and training standards shape diver behaviour, why many divers avoid formal reporting channels, and what other high-risk industries have done to build real learning systems. Gareth also shares how The Human Diver, the LEODSI investigation framework, and new industry standards are helping shift the focus from blame and compliance to understanding context, building trust, and creating lasting improvements in diving safety. Original blog: https://www.thehumandiver.com/post/cultural-infleunce-is-really-hard Links: Developing competencies and capacities for resilient performance: https://www.thehumandiver.com/post/resilient-performance-model Diving Talks: https://youtu.be/fUSD9gPZ-x0 Work as Imagined vs Work as Done: https://www.youtube.com/watch?v=vtgIwHrUWVQ&list=PLNXuyLsCTX6hHS3newpcROfJ_JiI27q3C&index=24 Standards: https://www.thehumandiver.com/post/beyond-the-floor Gareth’s Thesis: https://youtu.be/DRXqeQvRFK0 Flavours of Human Factors: https://www.thehumandiver.com/post/four-ways-of-hf LEODSI: https://www.thehumandiver.com/post/what-is-leodsi-petteot Chac Mool fatalities: https://www.thehumandiver.com/post/chac-mool-triple-diving-fatality Human Diver Conference: https://www.hf-in-diving-conference.com/ Rebreather Forum 4: https://youtu.be/nkdVHBDnCjc?t=3015 Maldives fatalities: https://www.thehumandiver.com/post/the-structure-is-normal-the-scale-is-not Events that happen without fatalities: https://www.thehumandiver.com/post/we-know-and-we-say-nothing Agencies using HF language: https://www.tdisdi.com/sdi-diver-news/how-serious-are-you-about-safety/ Levels of training available: https://www.thehumandiver.com/your-learning-journey Tags: THD-English| THD-Education & Content Type

This episode explores why experienced divers still die in situations that seem predictable, using the tragic 2026 Maldives cave accident as a starting point. It looks at how outcome bias, the normalisation of deviance, nitrogen narcosis, group dynamics, and silent drift can gradually erode safety margins without divers realising it. Rather than focusing on individual mistakes, the discussion explains how everyday decisions, accepted norms, and human psychology combine to create risk over time. It also examines what divers, teams, and the wider diving community can do to recognise these patterns, challenge unsafe habits, encourage open communication, and build a culture that learns from accidents instead of simply accepting them as bad luck. Original blog: https://www.thehumandiver.com/post/we-know-and-we-say-nothing Notes Concept formalised by Baron, J. & Hershey, J. C., "Outcome bias in decision evaluation," Journal of Personality and Social Psychology 54 (1988), p. 569-579. PDF available: https://www.sas.upenn.edu/~baron/papers/outcomebias.pdf Vaughan, D., The Challenger Launch Decision: Risky Technology, Culture, and Deviance at NASA, University of Chicago Press, 1996. Publisher page: https://press.uchicago.edu/ucp/books/book/chicago/C/bo22781921.html Lock, G., Under Pressure: Diving Deeper with Human Factors (2019); see also The Human Diver (https://www.thehumandiver.com) and the documentary If Only… (https://www.thehumandiver.com/ifonly). First systematic experimental demonstration: Behnke, A. R., Thomson, R. M. & Motley, E. P., "The psychologic effects from breathing air at 4 atmospheres pressure," American Journal of Physiology 112(3), 1935, p. 554-558. DOI: https://doi.org/10.1152/ajplegacy.1935.112.3.554 For an overview, see Nitrogen Narcosis In Diving on StatPearls (NCBI/NIH): https://www.ncbi.nlm.nih.gov/books/NBK470304/; and Clark, J. E., Moving in extreme environments: inert gas narcosis and underwater activities, Extreme Physiology & Medicine 3 (2014), which establishes that narcosis directly contributes to up to 6% of diving deaths — free full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4337274/ Hamilton, K., Laliberté, M. F. & Fowler, B., "Dissociation of the behavioral and subjective components of nitrogen narcosis and diver adaptation," Undersea & Hyperbaric Medicine 22(1), March 1995, p. 41-49 (PMID 7742709): https://pubmed.ncbi.nlm.nih.gov/7742709/ Bibliography Decision biases, normalisation of deviance, human factors Baron, J. & Hershey, J. C., "Outcome bias in decision evaluation," Journal of Personality and Social Psychology 54 (1988), p. 569-579. PDF: https://www.sas.upenn.edu/~baron/papers/outcomebias.pdf Vaughan, D., The Challenger Launch Decision: Risky Technology, Culture, and Deviance at NASA, University of Chicago Press, 1996. Publisher page: https://press.uchicago.edu/ucp/books/book/chicago/C/bo22781921.html Lock, G., Under Pressure: Diving Deeper with Human Factors, 2019. The Human Diver: https://www.thehumandiver.com. Documentary If Only…: https://www.thehumandiver.com/ifonly Physiology of narcosis Behnke, A. R., Thomson, R. M. & Motley, E. P., "The psychologic effects from breathing air at 4 atmospheres pressure," American Journal of Physiology 112(3), 1935, p. 554-558. First systematic experimental demonstration of the narcotic effects of compressed air at depth. DOI: https://doi.org/10.1152/ajplegacy.1935.112.3.554 Kirkland, P. J., Mathew, D., Modi, P. & Cooper, J. S., Nitrogen Narcosis In Diving, StatPearls (NCBI/NIH), last updated 2023: https://www.ncbi.nlm.nih.gov/books/NBK470304/ Clark, J. E., "Moving in extreme environments: inert gas narcosis and underwater activities," Extreme Physiology & Medicine 3 (2014). Free full text via PMC: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4337274/ Hamilton, K., Laliberté, M. F. & Fowler, B., "Dissociation of the behavioral and subjective components of nitrogen narcosis and diver adaptation," Undersea & Hyperbaric Medicine 22(1), March 1995, p. 41-49. PMID 7742709: https://pubmed.ncbi.nlm.nih.gov/7742709/ Diving accident research Divers Alert Network, Annual Diving Reports (long series, 1988 to 2021). Full collection consultable online: https://www.ncbi.nlm.nih.gov/books/NBK481542/ Exley, S., Basic Cave Diving: A Blueprint for Survival, National Speleological Society — Cave Diving Section, Branford (FL), 1979. Official NSS-CDS PDF: https://nsscds.org/wp-content/uploads/2018/05/Blueprint-for-Survival.pdf Buzzacott, P., Zeigler, E., Denoble, P. & Vann, R., "American Cave Diving Fatalities 1969-2007," International Journal of Aquatic Research and Education 3(2), 2009, p. 162-177. Free full text: https://scholarworks.bgsu.edu/ijare/vol3/iss2/7/ Potts, L., Buzzacott, P. & Denoble, P. J., "Thirty years of American cave diving fatalities," Diving and Hyperbaric Medicine 46(3), September 2016, p. 150-154. PMID 27723015: https://pubmed.ncbi.nlm.nih.gov/27723015/ Tags: THD-English| THD-Learning, Incidents & Just Culture

This episode explores how a restorative just culture can help the diving community respond to incidents in a way that promotes learning rather than blame. Instead of focusing only on who broke the rules, it looks at who was harmed, what they need, and how trust can be rebuilt while addressing the wider conditions that contributed to the event. The discussion covers the impact on everyone involved, the role of accountability, compassion, and forgiveness, and why repairing systems is more effective than simply punishing individuals. It also introduces Professor Sidney Dekker's Restorative Just Culture Checklist as a practical tool for turning difficult events into opportunities for meaningful learning and safer diving. Original blog: https://www.thehumandiver.com/post/2026-hfid-conference-what-did-you-miss Tags: THD-English| THD-Education & Content Type| THD-HFiD-Conference

This episode explores the difference between a retributive approach to diving incidents, which focuses on blame and punishment, and a restorative just culture, which focuses on learning, repair, and preventing future harm. It explains how incidents affect not only those directly involved but also instructors, organisations, and the wider diving community, and argues that real accountability means understanding what happened, supporting everyone affected, rebuilding trust, and fixing the conditions that allowed the event to occur. The discussion also introduces Professor Sidney Dekker's Restorative Just Culture Checklist as a practical tool for helping individuals and organisations move from blame to meaningful learning and lasting improvement. Original blog: https://www.thehumandiver.com/post/restorative-just-culture Links: The PDF checklist: https://drive.google.com/file/d/1Vkg0o4Fc8XWsAul-mkXNqD5lwokQ0ntP/view?usp=sharing Tags: THD-English| THD-Education & Content Type

This episode explores an important distinction that is often missed when discussing diving incidents: the difference between a cause, a reason, and an excuse. A cause explains what contributed to an event, a reason explains why a person's actions made sense to them at the time, and an excuse uses those reasons to avoid accountability. Understanding these differences helps us learn from accidents without simply assigning blame or letting people off the hook. The discussion shows why complex incidents usually have many interacting causes, why understanding local decision-making is essential for improving safety, and how separating learning from punishment leads to better conversations, stronger investigations, and safer diving for everyone. Original blog: https://www.thehumandiver.com/post/cause-reason-excuse Links: Accountability blog: https://www.thehumandiver.com/post/we-want-accountability RaDonda Vaught case: https://www.thehumandiver.com/post/the-structure-is-normal-the-scale-is-not Stop rules blog: https://www.thehumandiver.com/post/why-investigations-stop-where-they-stop Richard Cook’s diagram: https://www.thehumandiver.com/post/joining-dots-is-easy-if-you-know-the-outcome More about the RaDonda Vaught case: https://humanfactors101.com/2022/05/08/is-human-error-a-crime/ The eight question review: https://www.thehumandiver.com/post/eight-questions-about-maldives-accident “Learning” the same lessons: https://www.thehumandiver.com/post/why-does-nothing-change Tags: THD-English| THD-Learning, Incidents & Just Culture