SH251: Top Tips for Diving Instructors: Psychological Safety and the Thumb Rule

Counter-Errorism in Diving: Applying Human Factors to Diving · Feb 7, 2026 · 5m

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 —…