How much narcosis is acceptable/'normal'?

[drbill]

When I was diving to 180-200 fsw solo on air, I wasn't willing to tolerate much narcosis since I was alone. If I couldn't locate, frame and follow my subjects with my video rig, I ascended to a shallower depth. Fortunately that rarely happened back when I was doing hundreds of dives a year, many of them deep. When I resumed more shallow dives, I got narced on several of them. I don't do any diving below about 125 fsw these days.

If you're diving with a team, you're in a much better position. I would never take a buddy that deep with me.On several of my deep dives I did have tech divers nearby.

 

[Nasser]

Although I don't dive a CCR I do calculate my END for Trimix dives and I have found that there's no one size fits all. It is dependent on the diving conditions such as water temp, level of activity and stress, are you in an overhead environment? and of course your own susceptibility (which you may not always realize) on any given day.

The best thing is to assess all these factors on any given dive and decide what's acceptable for you.

FWIW on OC I usually can dive with an END of 40m in warm, calm, water on a familiar site and I'm o.k. but if the conditions are a little more challenging or I'm doing a penetration than I'll knock it back to 3.1 - 3.5.

 

[lermontov]

on a sliding scale- warm tropical water , clear vis, calm, - straightforward dive then tend to tolerate more narcosis- cold water poor vis etc then less so

 

[Storker]

on a sliding scale- warm tropical water , clear vis, calm, - straightforward dive then tend to tolerate more narcosis- cold water poor vis etc then less so

I'm hearing this a lot, and I wonder: is it because warm water and clear vis in some magical way makes you less narked, or is it because cold water, heavy exposure protection and poor vis task loads you more, so you feel the nark more easily?

If the latter at least I would be careful accepting a deeper dive on air in warm, clear water than I would in cold, murky water. Because if SHTF I'll need all my mental bandwidth to handle the situation and I'll be just as impaired even if I didn't notice it as easily before SHTF.

 

[Dominik_E]

I think it is both. Narcosis, like all things that effect cognition, is never disentangled from what the subject makes of it.

 

[lermontov]

I'm hearing this a lot, and I wonder: is it because warm water and clear vis in some magical way makes you less narked, or is it because cold water, heavy exposure protection and poor vis task loads you more, so you feel the nark more easily?

If the latter at least I would be careful accepting a deeper dive on air in warm, clear water than I would in cold, murky water. Because if SHTF I'll need all my mental bandwidth to handle the situation and I'll be just as impaired even if I didn't notice it as easily before SHTF.

I guess the PN2 is identical so there either be some psychologic factors that magnify the narcosis in cold dark water or I just feel more comfortable in warm clear and thus maybe dont recognise it - its hard to know without doing some sort of empirical test , but one can't deny that state of mind has an effect on managing stress or tasks

 

[kensuf]

CO2 buildup from working harder.