Hydro Atlantic without Helium?

[Kevrumbo]

To minimize CO2 retention/hypercapnia due to physical exertion at depth, you gotta have a DPV/Scooter provide all your mobility -especially if going against a current at depth- if you're going to dive Deep Air. . .

 

[PfcAJ]

You know... I was tech diving before trimix really was mainstream and it took me a while to adopt it. I also used to run a tech shop. I think it's safe to say that I'm serious about tech diving. That whole if you can't afford it thing really erks me. I can afford it. I just don't like to spend money if i dont need to. I'd rather be diving than diving and spending extra cash so I can be one of the cool kids. Diving 150 on air is safe in my opinion and I've done it many many times. I have many sets of tanks and more tech gear than I know what to do with it. Again, it was a simple question does anyone dive this wreck on nitrox. Tech diving doesn't mean absolute use of trimix if that's your definition.

If you think it’s safe and you have all this experience why are you asking for permission on scubaboard. If money is no object then why wouldn’t you use helium?


¯\_(ツ)_/¯

 

[dave22387]

If you think it’s safe and you have all this experience why are you asking for permission on scubaboard. If money is no object then why wouldn’t you use helium?


¯\_(ツ)_/¯

I am certainly not asking permission. Just attempting to get a feel from local divers if they dive it without mix. Who knows, maybe someone would tell me that a boat won't even take me without mix... I have been on boats off of NJ that won't let you on unless you're diving a similiar profile to the other divers... What good is this forum if we can't discuss things??? As far as the money, just because it's in the bank doesn't mean I have to spend it if it isn't necessary. Money is always an object.

 

[RyanT]

Here's something that has become more clear to me over the years. Narcosis is variable. About 20 years ago, my dives become very homogenous. Mostly 125-135 fsw on a friend's boat, diving air, often diving solo with no rush to gear up. I made a couple of dives to 190' or more on air. On most of those dives there was very little current, the water was reasonably warm, and the vis was pretty good. I always felt a tiny bit of narcosis at around 130' but anything shallower than 130' and I felt nothing. I remember a couple of dives then to 175' on air where I didn't have any noticeable increase in narcosis over my 130' dives. Those deep dives also consisted of warm, good viz, low current dives. At that time, I came to assume that 130' was really the "edge" where narcosis began to manifest itself for me and a good atmosphere deeper really had no additional affect.

Fast forward to today. In the past three years I've started diving deeper and in much more variable conditions. These variable conditions include lower viz, lower water temps, increased current (e.g. workload), and crowded conditions on a commercial boat. I've found that any one of these things noticeably increases my narcosis. Let a couple of these factors stack up and I'm finding myself noticeably narced at 110' on air/nitrox. This experience makes me like helium more and more for even fairly moderate depths.

 

[dave22387]

Here's something that has become more clear to me over the years. Narcosis is variable. About 20 years ago, my dives become very homogenous. Mostly 125-135 fsw on a friend's boat, diving air, often diving solo with no rush to gear up. I made a couple of dives to 190' or more on air. On most of those dives there was very little current, the water was reasonably warm, and the vis was pretty good. I always felt a tiny bit of narcosis at around 130' but anything shallower than 130' and I felt nothing. I remember a couple of dives then to 175' on air where I didn't have any noticeable increase in narcosis over my 130' dives. Those deep dives also consisted of warm, good viz, low current dives. At that time, I came to assume that 130' was really the "edge" where narcosis began to manifest itself for me and a good atmosphere deeper really had no additional affect.

Fast forward to today. In the past three years I've started diving deeper and in much more variable conditions. These variable conditions include lower viz, lower water temps, increased current (e.g. workload), and crowded conditions on a commercial boat. I've found that any one of these things noticeably increases my narcosis. Let a couple of these factors stack up and I'm finding myself noticeably narced at 110' on air/nitrox. This experience makes me like helium more and more for even fairly moderate depths.

I agree with you wholeheartedly on this. My narc level is certainly variable. I am not necessarily advocating for deep air over He. We all know He is the way to go if available. If I had a big tank of helium in my garage there wouldn't even be a question. I just wanted to see if there is still some people who dive this wreck on nitrox. Thanks for the i

 

[northernone]

I'm not local there, just watched a couple videos of the dive site. My opinion is exactly that. I'm happy and confortable on air at 150 in way worse conditions so that's what I'm basing my reply on.

I'd not dream of wasting helium on that dive unless there was some compelling reason (complex navigation or data collection). Even if helium was free, it's still a precious resource. From a safety perspective, it introduces complexity to a simple dive.

I 'could' spend the money on helium for a 150ft dive and in bad conditions I'm glad for it much shallower. That said... No need to waste it on dives where experience and comfort have shown it to be unnecessary.

What depth that is for you, is up to you and anyone nearby who might need to save your @ss if you go bovine stupid in an emergency at depth.

...And the scuba police. ; )

Dive and let dive.
Cameron

 

[markmud]

Hello OP,

I don't have an opinion because I am not a tech diver.

I am enjoying this thread, so thanks for creating it!

markm

 

[doctormike]

Speaking of narcosis and the Hydro Atlantic, here's John Chatterton on that exact topic. Entertaining and informative. Hint. It's not just nitrogen...

 

[Tom Winters]

I made the mistake of reading this thread while breathing the ambient air in my living room. My tanks are in my car, and I thought that I could read Scubaboard without mixed gas.
I’m horribly narc’ed right now...I read the Chatterton thing and I can’t figure out why Stevie Wonder is pointing a sawed-off shotgun at me.

 

[boulderjohn]

I have done that dive quite a few times, and always on trimix. I would say that on those recent dives on the boats I have been on, pretty much everyone is on mix. However, I remember past dives to that wreck and others in that range where people were on air. I remember one dive years ago on which we all had to do our deco hanging on the line in current. I spent a long, long time hanging onto the line and staring at the analysis sticker of the tank inches below me, and it said "AIR." I spent most of that time thinking about this very issue.