PADI AOW - Narcosis Training?

[RainPilot]

Okay, A good, safe, consistent, practical way to demonstrate narcosis underwater.

I was shown a good one the other day, I need to get onto making my own before I next teach a deep course.

The instructor had a wet notes page with a grid of numbers from 1- 50 (iirc) arranged randomly, along with "L EAR" "R EAR" and "NOSE" written on top. On the surface, we were asked to point to the 1, then touch eg your nose, then 2, nose again, and so on. Time was taken.

At depth, exercise repeated with a different body part eg left ear pointed to on the sheet and then timed.

The instructor had 3 or 4 differently arranged sheets so you had a different exercise but the same process.

It addressed the problem of task familiarity pretty well, my UW time at 40m basically doubled. It was the first time that I had been demonstrated how I was narced even though I felt absolutely fine. In the past the exercises had always seems forced and had never generated enough performance delta to be convincing.

ETA: Ok got off my butt and made a first one so you can see. A5 for lamination, if you want the raw Excel file just drop me a PM. Oh and I put the body part in red so it can double as a colour-loss indicator as well.

 

[Zef]

There is no safe and practical way to induce/demonstrate narcosis in the water. Narcosis is impairing by its nature. The people who are guiding the exercise can be just as affected as the people who are meant to observe or experience it, which can lead to lapses in judgement.

One issue with narcosis and recreational diving is that its onset typically occurs at a depth where the diver is no longer just limited by the amount of air they are carrying, but instead no-deco time becomes a very pertinent factor, and this is coupled with the increased consumption from the tank due to the increased depth/pressure. If one does not stay aware or misinterprets, or disregards their bottom time and air reserves due to the affect of narcosis they can easily find themself in quite a dangerous predicament.

A chamber would be the only safe, practical way to induce narcosis. The questions is like asking how can one induce the affect of being drunk behind the wheel of a car in a safe practical way while rejecting the notion that an expensive simulator is not practical....the major difference is that you can put a vehicle in large open space secure from any other traffic (such as a track) and induce inebriation in the test subject, there really is not an equivalent in a diving environment for someone to experience.

-Z