What is your personal "Helium" Depth?

[kensuf]

It depends.

Caribbean reef diving? My willingness to dive deeper without helium goes up. 130'-150'.

Deep dark caves? I'm on mix much shallower. 100-120'.

CCR? I drive my CCR from my off-board bailout, and those are filled with trimix. So if I'm on the loop, I'm on mix (I dove 21/35 DIL for a 5 hour dive at Peacock on Saturday).

 

[lv2dive]

CC is almost always mix, bc why not?

OC it depends... In caves I'm with AJ, I prefer some mix in the tanks starting around 80' - I've dived deeper on Nitrox but since I started diving a CCR I am spoiled and think I should probably stick to 80'. In general, 100' is my max without mix, but in OW but there could be an extenuating circumstance here or there. (I cut my diving teeth on NC wrecks before I learned air was just for tires so I do have some experience to fall back on . But - i haven't found a situation that warranted it in the past five years)

 

[ajduplessis]

Approaching 150 feet diving dry. I cant justify helium any shallower.

 

[100days-a-year]

200' I video a lot of dives and there isn't any perceivable performance drop-off but I start feeling uncomfortable at 180' and more silly than I like beyond that.

Most of my dives are very repetitive being spearfishing so there are rarely new tasks.
I dive primarily in 72 to 80+ degree waters.
Vis is typically 50+ but ranges 10' to ridiculously clear.
I was taught that narcosis is subjective,can be mitigated and dealt with and I haven't seen any reason to not believe it in my case.YMMV

 

[Doppler]

In my helitrox deco courses and trimix courses 30 metres is the preferred benchmark for introducing helium into one's backmix. The 45-metre limit is suggested as an extreme when helium is unavailable... for me, that depth is extreme even in very warm water. In cold water, even 30 metres is deep.

On CCR, there is probably helium in my diluent for most dives. CERTAINLY any below 25 metres.

 

[rivers]

Generally, if a majority of the dive is going to be deeper than 35m, then I'll use 21/35. If I'm on a dive where the bottom of the wreck sits at 35m max, but a majority of it is 30m or shallower, I'll use 32%.

 

[Dr Simon Mitchell]

I have just posted a link to a very relevant research document here:

Gas density guidelines

Simon M

 

[Diver0001]

I understand that the DIR community considers anything below 100 feet to be Helium territory. PSAI is the other extreme with their "Narc Management" courses. TDI lies somewhere in the middle with 150 feet to be the limit for Decompression Procedures course. I just wanted to ask tec divers that if you were doing something that involves concentration such as DSLR photography (not the point and shoot but DSLR) or laying a reel etc. at what depth does Helium becomes necessary for you for such tasks?

Personally I'd be in the 35-40m range

 

[Storker]

I have just posted a link to a very relevant research document here:

Gas density guidelines

That reports seems to deal exclusively with CC. Would you use the same gas density guidelines on OC?

 

[RainPilot]

That reports seems to deal exclusively with CC. Would you use the same gas density guidelines on OC?

I think that the CO2 retention issues are pretty similar, obviously CCR specific factors like WOB with counter lung placement etc will complicate the issue but generally the guidelines seem to make sense for OC and CC.

For me, the layman, anyway...