This episode explores the fatal case of 18-year-old Linnea Mills to show how visible hazards can go unnoticed when an instructor lacks the mental capacity to recognise them. Linnea was overweighted, unable to inflate her drysuit, and using equipment that couldn’t provide enough lift—risks that seem obvious in hindsight but were missed due to a combination of inexperience, time pressure, unfamiliar gear, and commercial expectations. Using models like ECOM and COCOM, the episode explains how an instructor’s attention can be consumed by immediate tasks, leaving no capacity to monitor the bigger picture or reassess whether a dive should proceed. This isn’t about blaming an individual, but understanding how systems, workload, and limited experience can overwhelm decision-making. The key lesson is that effective instructors don’t just rely on skill, but on preparation—setting clear plans, checks, and limits before the dive—to protect their ability to recognise problems when it matters most.

Original blog: https://www.thehumandiver.com/post/the-obvious-thing-nobody-noticed

Links: Part 1: https://www.thehumandiver.com/post/the-picture-went-dark

The Linnea Mills case: https://www.thehumandiver.com/post/linnea-mills-death-hf-systems-lens

Tags: English| Sense-making, Decision-making, & Psychology