SH251: Top Tips for Diving Instructors: Psychological Safety and the Thumb Rule
Sat Feb 07 2026
This episode explores why calling a dive can be harder in practice than the famous “any diver can end any dive” rule suggests, especially for instructors under time, money, or reputation pressure. Using a real cave-diving example, the blog shows how small equipment issues and disrupted routines created warning signs that the team wasn’t ready, even though nothing had gone seriously wrong yet. The dive was safely called, and the team later recognised how important psychological safety was in making that decision feel acceptable and supported. The key message is that psychological safety — feeling able to speak up, admit mistakes, or stop without fear of criticism — is essential for safe and effective training. Instructors play a major role in creating this by staying calm under pressure, reacting constructively to small problems, and leading by example when it’s time to call a dive.
Original blog: https://www.thehumandiver.com/blog/top-tips-for-diving-instructors-psychological-safety-and-the-thumb-rule
Links: Some previous blogs about psychological safety:
https://www.thehumandiver.com/blog/HFforD-part-10-psychological-safety
https://www.thehumandiver.com/blog/what-if-just-culture-and-psychological-safety-is-not-enough
https://www.thehumandiver.com/blog/the-challenge-of-psychological-safety
https://www.thehumandiver.com/blog/what-we-get-wrong-about-psychological-safety-in-diving
https://www.thehumandiver.com/blog/top-tips-for-beginner-divers-psychological-safety-just-culture
https://www.thehumandiver.com/blog/team-building-psych-safety-1 - Part one of a four-part series.
Tags: - english cave diving human factors lanny vogel psychological safety a href="https://www.thehumandiver.com/blog?tag=teamwork" rel="noopener noreferrer"...
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This episode explores why calling a dive can be harder in practice than the famous “any diver can end any dive” rule suggests, especially for instructors under time, money, or reputation pressure. Using a real cave-diving example, the blog shows how small equipment issues and disrupted routines created warning signs that the team wasn’t ready, even though nothing had gone seriously wrong yet. The dive was safely called, and the team later recognised how important psychological safety was in making that decision feel acceptable and supported. The key message is that psychological safety — feeling able to speak up, admit mistakes, or stop without fear of criticism — is essential for safe and effective training. Instructors play a major role in creating this by staying calm under pressure, reacting constructively to small problems, and leading by example when it’s time to call a dive. Original blog: https://www.thehumandiver.com/blog/top-tips-for-diving-instructors-psychological-safety-and-the-thumb-rule Links: Some previous blogs about psychological safety: https://www.thehumandiver.com/blog/HFforD-part-10-psychological-safety https://www.thehumandiver.com/blog/what-if-just-culture-and-psychological-safety-is-not-enough https://www.thehumandiver.com/blog/the-challenge-of-psychological-safety https://www.thehumandiver.com/blog/what-we-get-wrong-about-psychological-safety-in-diving https://www.thehumandiver.com/blog/top-tips-for-beginner-divers-psychological-safety-just-culture https://www.thehumandiver.com/blog/team-building-psych-safety-1 - Part one of a four-part series. Tags: - english cave diving human factors lanny vogel psychological safety a href="https://www.thehumandiver.com/blog?tag=teamwork" rel="noopener noreferrer"...