Nitrogen narcosis and alcohol use.

[bleeb]

That's right! I remember you swimming right next to me watching me the entire dive.

No one has to have been swimming next to you to know you were probably narced. Warm dry test subjects in hyperbaric chambers pretty well all start showing the measurable degradation in mental function of narcosis after only 30-60'. Even when significantly deeper, divers often don't think they feel any of the classic symptoms of narcosis, or don't often need to do much original thinking, such as might be needed in an emergency. Even the common math or puzzle tests used in many AOW or Deep courses don't seem to be all that accurate an indicator, since they can be too simple or mechanical for many people. But at 110+' you were almost certainly narced, unless maybe you were breathing Trimix with a lot of He.

 

[Rhone Man]

I have used this anecdote before, so I'll throw it again (although I doubt it adds value to the discussion at this point).

If you don't believe you have ever been narc'ed below 100 feet, try this simple exercise. Next time you dive below that depth, switch your gauges from imperial readings to metric (ie. meters and bar). Clearly this is easier to do with a dive computer than analogue gauges. Then mentally convert the numbers back during your dive. What is very easy at the surface becomes much more challenging below 100 feet.

I did it once, and it was pretty startling.

 

[BoltSnap]

Rhone Man,

What if you don't know how to convert to begin with anyways?

 

[bleeb]

What if you don't know how to convert to begin with anyways?

Multiply by 3.281. What could be easier?

 

[BoltSnap]

But I can't do that without a calculator on the surface? Is there an easier test?

 

[BoltSnap]

BTW, I am not sure that you can change the configuration settings for dive computers U/W (imperial <-> metric), can you?