What is the Shallowest Depth at which You Notice Narcosis?

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Tropical warm water 30deg C, around 48m and absolutely stoned at 60m.
Temperate SoCal homewaters presently around 12 -15deg C at depth, shallow narc at 21m and totally tharn by 39m.
 
I only seem to feel the effects at the beginning of a dive on the way down on dives deeper than 80'-85'.
My typical drill is to stop on the bottom for a very brief time (a minute or less), and move on when things seem normal.
Or as normal as you can feel with several atmospheres pressing in on you.
Chug
Thinks it is worse when it's cold.
 
Cold, dark, low vis I know for sure Ive been noticeably narced once at 95-100ft.
I however did NOT feel it and realize it while it was happening, but I did indeed realize after the dive.
I learned to be a bit more "on top of things" when diving that deep in cold, low vis situations.
When diving in the tropics its generally less gear (thus work), warmer and better vis and I cant notice any ill effects untill atleast 110ft, but I know its there to some degree...
 
Generally the most narcotic gas we regularly encounter in diving is Carbon Dioxide which is about 20 times more narcotic than Nitrogen. Any kind of work that can lead to increased CO2 can also result in a big increase in narcosis, this can make deep narcosis a lot worse but can also bring on less severe narcosis at shallower depths. Add cold temperatures and bad visibility into this and narcosis at 20m/70ft is possible, although it shouldn't be too bad!

One of the main symptoms of narcosis is a lack of awareness what is happening around you, this is normally easier for others to spot than yourself so it's quite hard to really know just how much you were narked. The main thing is to appreciate everyone gets narked, we normally deal with it but if a situation suddenly gets bad and increased breathing, worry and CO2 build-up sets in it a lot, lot harder to solve than it would be with a clear head and no narcosis.
 
I dont dive tri mix unless I'm outside of rec depths.
 
I haven't experienced it yet and I routinely dive deep. My deepest dive has been to 165 feet and I was taking macro photographs. No evidence of any problems when I checked them later. My fiancé and instructor was with me and was watching me for signs of narcosis. He saw none. He doesn't experience it until 180 feet, which he hasn't been to for several years.
 
I regularly dive to 100-103 ft on both air or ean 32 and haven't noticed any feeling narcosis myself and haven't noticed it in my buddy either, nor has he noticed it in me. Though I suppose it's possible we both were equally narced. Never had a problem manipulating my camera but never tried the writing test.
 
Generally the most narcotic gas we regularly encounter in diving is Carbon Dioxide which is about 20 times more narcotic than Nitrogen. Any kind of work that can lead to increased CO2 can also result in a big increase in narcosis, this can make deep narcosis a lot worse but can also bring on less severe narcosis at shallower depths. Add cold temperatures and bad visibility into this and narcosis at 20m/70ft is possible, although it shouldn't be too bad!

One of the main symptoms of narcosis is a lack of awareness what is happening around you, this is normally easier for others to spot than yourself so it's quite hard to really know just how much you were narked. The main thing is to appreciate everyone gets narked, we normally deal with it but if a situation suddenly gets bad and increased breathing, worry and CO2 build-up sets in it a lot, lot harder to solve than it would be with a clear head and no narcosis.

I did definitively feel CO2 building up in my system during a dive when I was working hard at 30 ft. it was awful. My brain wanted to rush my body to the surface because the CO2 made me feel as if I was suffocating.
 
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never happened yet. I'm goofy before I ever get into the water, maybe that has something to do with it. :wink:
 
Cold also have a direct impact on narcosis. My instructor years ago took me on a quick intro to twins in the middle of winter. Water temp was below 10 Celcius (50f) and he could not perform a basic valve drill at the 30ft platform. He was in 5mm wetsuit and no hoodie.

I am still not sure if it was narcosis or brain-feeeze.
 
https://www.shearwater.com/products/teric/

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