Counter-Errorism in Diving: Applying Human Factors to Diving

In this episode, Connor Tate shares her experience of attending the Human Factors in Diving Conference while struggling with imposter syndrome as a researcher with limited diving experience. Despite understanding the science behind stress and decision-making, Connor discovers the difference between studying these concepts and experiencing them first-hand when a mask-clearing problem at depth triggers the early signs of panic. With the calm assistance of an experienced diver, she completes the dive and later reflects on how the experience connects directly to their research into detecting stress underwater. Through structured debriefs, practical training and an environment where people can discuss mistakes without blame, the conference demonstrates the value of psychological safety, teamwork and learning from experience. Connor also discovers that these lessons apply beyond diving, using human factors tools to improve communication and accountability at work. Ultimately, the experience shows that everyone has something valuable to contribute, regardless of their level of experience, and that progress comes from being willing to learn, reflect and be better than yesterday.

Original blog: https://www.thehumandiver.com/post/am-i-enough

Links: Join us at next year’s Gathering: https://www.hf-in-diving-conference.com/

Tags: THD-English| THD-Education & Content Type| THD-HFiD-Conference

We explore how capable, motivated divers can gradually push beyond safe limits when their environment rewards risk-taking and treats near misses as successes. Using the story of a young technical diver who died after entering a strong current, alongside examples from aviation, we examine how normalisation of deviance, practical drift, peer pressure and the need for recognition can erode safety margins over time. The episode asks whether we are recognising skill or simply rewarding luck, and looks at the responsibility of instructors, dive centres and teammates to create an environment where people can challenge decisions and stop a dive without fear of criticism. In an activity where there is no higher authority to stop a diver from making a poor decision, the people around us may be the last line of defence. The challenge is to tell these stories not as tales of foolish people making bad decisions, but as opportunities to understand how reasonable decisions can lead to terrible outcomes—and to recognise the early warning signs in our own thinking before it is too late.

Original blog: https://www.thehumandiver.com/post/cashing-cheques

Links: Blog about Normalisation of Deviance: https://www.thehumandiver.com/post/normalisation-of-deviance-not-about-rule-breaking

Lucky and good are different things: https://www.thehumandiver.com/post/were-you-lucky-or-were-you-good-2

Jon Kieran’s article about training Doc Deep: https://indepthmag.com/i-trained-doc-deep/

The factors that allowed Holland’s fatality: https://convergentperformance.com/wp-content/uploads/attachments/Darker_Shades_of_Blue.pdf?srsltid=AfmBOoqA5a510blcq1IOFitrQHksCF-mGJHc_5W7wcAmC1fl8A-MN7B5

Discussion about the term “second victim”: https://www.medstarhealth.org/-/media/project/mho/medstar/institute-for-quality-and-safety/about-miqs/abandon-term-second-victim-2019_web.pdf

Calling a dive: https://www.tdisdi.com/sdi-diver-news/a-secret-tip-for-safer-diving/

Sidney Dekker’s checklist: https://www.thehumandiver.com/post/restorative-just-culture

References/Resources: Dillon and Tinsley. Near-miss events, risk messages, and decision making. & How Near-Miss Events Amplify or Attenuate Risky Decision Making

Fit to Dive - Dealing with trauma after a diving accident

Tags: THD-English| THD-Learning, Incidents & Just Culture

This episode explores Human and Organizational Performance (HOP), an approach to safety that starts with the idea that people will always make mistakes, so we should focus on understanding why decisions made sense at the time rather than simply blaming individuals. Drawing on a workshop from the Human Factors in Diving Conference in Vis, Croatia, we look at how HOP can be applied to diving by considering the conditions, information, equipment and pressures people were working with. Using a hypothetical case of a dive boat leaving two divers behind, we compare traditional incident investigations with a more curious approach that looks at the wider context, including workload, fatigue, schedules, group dynamics and the pressures faced by the crew. Most importantly, HOP encourages us to learn from everyday work rather than waiting for something to go wrong, asking what makes things succeed and where risks might be hiding. The episode considers how regular debriefs and humble inquiry can help teams learn, improve and build safer systems without relying on blame.

Original blog: https://www.thehumandiver.com/post/steve-smith-applying-hop-lucky-or-good

Tags: THD-English| THD-Education & Content Type| THD-HFiD-Conference

This episode explores what really makes complex technical diving successful: not just helium, decompression and equipment, but the people using them. Using the recovery of the WWII B-24 Liberator Tulsamerican off the island of Vis as a case study, we look at how communication, teamwork, workload management, clear goals and psychological safety can make the difference between a team that simply completes a dive and one that achieves its mission safely. The project brought together divers, archaeologists, historians, military agencies, local authorities and vessel crews from different backgrounds and countries, creating the kind of complex environment where human performance becomes critical. The story shows how small mistakes can quickly become team problems, why anyone should be able to speak up or call a dive, and how focusing on the wider mission can help prevent individual ambition from driving poor decisions. Ultimately, the Tulsamerican recovery demonstrates that technical diving is about far more than what we carry into the water—it is about how effectively we work together.

Original blog: https://www.thehumandiver.com/post/more-than-a-deep-dive

Tags: THD-English| THD-Education & Content Type| THD-HFiD-Conference

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

1. 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
2. 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
3. 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).
4. 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
5. 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/
6. 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/

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

This episode explores why accident investigations often stop long before they uncover the full picture. Drawing on research from safety science, it argues that the “cause” of an incident is not simply discovered—it is shaped by who is investigating, what they are able to change, and what explanations their community accepts. In diving, investigations often focus on the actions of individual divers or instructors because these are the easiest problems to address, while deeper issues such as organisational culture, commercial pressures, and industry practices are left unexplored. The episode examines how different people can interpret the same event in very different ways, why every investigation helps shape the community’s understanding of safety, and why asking “Why did the investigation stop here?” can lead to far richer learning than simply accepting the reported cause.

Original blog: https://www.thehumandiver.com/post/why-investigations-stop-where-they-stop

Links: The most complete data on diving fatalities from 2008: https://pubmed.ncbi.nlm.nih.gov/19175195/

Blog exploring the purposes of running an investigation: https://www.thehumandiver.com/post/what-is-the-purpose-of-an-investigation

LFEO program: https://www.thehumandiver.com/lfeo

HFiD conference: https://www.hf-in-diving-conference.com/

What you look for is what you find: https://doi-org.ludwig.lub.lu.se/10.1016/j.ssci.2009.01.004

What you find is what you fix: https://doi-org.ludwig.lub.lu.se/10.1016/j.aap.2010.07.003

Blog about agency/organisation standards: https://www.thehumandiver.com/post/beyond-the-floor

Speaking truth to power: https://www.thehumandiver.com/post/when-im-fine-isnt-true

Structural conditions that produce decisions: https://www.thehumandiver.com/post/the-structure-is-normal-the-scale-is-not

Other references:

Blazsin, H. & Guldenmund, F. (2015). The social construction of safety: Comparing three realities. Safety Science, 71, 16–27.

Lundberg, J., Rollenhagen, C. & Hollnagel, E. (2009). What-You-Look-For-Is-What-You-Find — The consequences of underlying accident models in eight accident investigation manuals. Safety Science, 47(10), 1297–1311.

Lundberg, J., Rollenhagen, C. & Hollnagel, E. (2010). What you find is not always what you fix — How other aspects than causes of accidents decide recommendations for remedial actions. Accident Analysis and Prevention, 42, 2132–2139.

Rasmussen, J. (1990). Human error and the problem of causality in analysis of accidents. Philosophical Transactions of the Royal Society of London B, 327, 449–462.

Rochlin, G. I. (1999). Safe operation as a social construct. Ergonomics, 42(11), 1549–1560.

Shreeves, K., Buzzacott, P., Hornsby, A., & Caney, M. (2018). Violations of safe diving practices among 122 diver fatalities. Int. Marit. Health, 69(2), 94–98. https://doi.org/10.5603/imh.2018.0014

van der Schaaf, T. W., Lucas, D. A. & Hale, A. R. (1991). Near miss reporting as a safety tool. Butterworth-Heinemann.

Tags: THD-English| THD-Learning, Incidents & Just Culture