How common is deep air? NHZ

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Jeremy
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Re: How common is deep air? NHZ

Post by Jeremy »

This is a NHZ thread so I'll comment a little further.

Why are new students encouraged to take Rescue Diver class? The reason I was given was so that "we can become a better buddy."

Why take team diving classes and go through all that torture? The bottom line is that we want to become better buddies....more than just go deep or go into a cave. We learn underwater etiquette, underwater communication, and underwater conservation. We learn to utilize team resources and how to overcome seemingly insurmountable underwater challenges.

A good buddy doesn't dive for just themselves. They want to have a good time and they want their buddy to have good time. Safety is paramount.

So....suppose we want to be great buddies to our diving partners. Can we accomplish that on air at 130'? For me, and for all my training, the answer is no. If shit goes south at 130.....and I'm narced as expected (even though I didn't feel narced at all in a non task loading situation)...things will go from bad to worse in a hurry. So I don't put myself or my buddy in that situation.
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BillZ
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Re: How common is deep air? NHZ

Post by BillZ »

Mateo1147 wrote:
pensacoladiver wrote:You just don't know what you don't know.
Yeah what he said. I fall into that category. I will dive 21% to 150'+ and don't feel like I'm not with the program. I was with J Pack at Leshi wall that deep on tire gas. Only one time did I feel narced out of my head and I was on nitrox! It was only 25% O2 but still nitrox.
It comes down to money. I can't afford advanced nitrox, tec one, tec two, trimix one, trimix two. The only course of action for me right now is to stay shallow, i.e. 130' or less or I double the depth of stop on my computer. After my trip to the chamber I was educated about computer algorithms and how aggressive some are. So now if my computer says I owe three minutes at 10' I stay at 20' until that obligation clears. The obvious solution is to upgrade to a full Tec computer and buy the TDI tec manuals from DGX and do a self study course.
I may catch hell but I'm being honest about what I am doing.
Couple of points - I hope I don't come off as violating NWDC rule #1 :)
Being narced doesn't necessarily mean that you're feeling out of your mind or drunk. Most of the time it just causes a fuzziness that impairs your ability to react and can cause your stress level to go from zero to 100 in a heartbeat. Both of which are not optimal if you have an issue at depth.

Simply doubling your computers ceiling depth is not really a viable deco procedure.

If you can't afford the training to dive deep wait until you can, the divesites will still be there. :)
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ljjames
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Re: How common is deep air?

Post by ljjames »

My trimix class was $1200 + gas + boat charter + cert + the travel costs to get to San Diego, so over 2K when all was said and done... Basically all the money I had in the world when i was a broke college student/even broker tech dive shop owner. It was cheaper than going to Florida which was the only other option. It was kind of a leap of faith, no one was doing it out here recreationally, there were no tables, no computers, etc.. We did for safety reasons. I was concerned about diving the Bunker Hill on air with the currents and the bottom in 270. We'd been diving the Al-Ind-Esk-A Sea and although I never had a 'close call' on air, we used to do narcosis tests and we were all very impaired. In fact, the only close call I've ever had diving was dealing with a panic-y dive buddy who was on air (I was on mix) on the Sea, and I am very very glad I had a clear head that day.

The question I asked myself isn't 'am I too impaired to dive', it's am I too impaired to help someone (or myself) out in an emergency'. I've done deep air, deeper than i care to admit now a days, and ya, when you are just free falling to depth, and then moseying up a silty slope and not building up an CO2, you may not have any issues.... BUT, as soon as you add in some current, some swimming, having to do a task, babysitting students, building up some CO2, etc... its a whole new ballgame.

Did I dive deep air, yes, but only so I could dive shipwrecks. Do I now, no. Why? because I have a rebreather which keeps me well supplied with nitrox and trimix. Do some folks still do it, i imagine so, but less and less is the trend i'm seeing/hearing about. Would I do it again here in our current-y dark cold water? no. Would I do it in.. say... Truk? 100' vis, warm water, etc.. If i couldn't take my 'breather, sure, within reason.

When we were teaching we got people hooked on mix by taking them on a 'trimix experience dive' It wasn't a super deep dive, they had to already be advanced nitrox certified (so some basic decompression protocol) we'd trot them down to 130' on some mix and if they felt really adventuresome, let them switch back to air at ~100', and experience the difference whilst doing some timed skills like a those shape puzzles or some math. A bit cavalier perhaps, but it was the wild wild west back then ;)

Narcosis is warm and fuzzy, till it isn't.


Mateo1147 wrote:
ljjames wrote:We dived deep air because it was the only option. It was NOT a right of passage. My dive buddies and I stopped diving air past about 60' the day we got helium certs. That was in 1992-ish so I'm guessing we count as 'old-timers'.

I don't teach any more, and it's been like 100 years since I taught any tech, but in my experience the people who came to us for classes did so specifically because they didn't WANT to dive deep air. They had bigger plans that included deep wrecks and walls, and wanted to remember the dive.
Just out of curiosity how much did a cert to dive trimix cost 100 years ago? It appears to me that unless I want to part with $2K I can't discover the wonders of trimix.
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Jeff Pack
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Re: How common is deep air? NHZ

Post by Jeff Pack »

Jeremy wrote:
Jeff Pack wrote: That was to 174 without substantial impairment. I wasn't 100%, but I wasn't looped outa my gourd either.
I'm curious how you determined you were not substantially impaired at 174'. My understanding is that you can be dangerously impaired from narcosis without noticing it....you only find out when you unfortunately become task loaded...such as a situation where you need to assist a buddy in trouble. My understanding is also that this "not knowing" type is the most frequent type of narcosis....the less frequent types are where you know you are narced and it's obvious to you.
There are tests you can mentally take to determine your level of clarity. Multi tasking types are the best.
=============================================

- I got a good squirt in my mouth
- I would imagine that there would be a large amount of involuntary gagging
- I don't know about you but I'm not into swallowing it

CCR discussion on Caustic Cocktails.
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ljjames
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Re: How common is deep air? NHZ

Post by ljjames »

and have your buddy (hopefully on trimix) video tape you <grin>
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Jeff Pack
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Re: How common is deep air? NHZ

Post by Jeff Pack »

ljjames wrote:and have your buddy (hopefully on trimix) video tape you <grin>
Yea, after watching Jeff fumble around on Sledgehammer connecting his MAV to off board dil, would have made a great video of the evils of narcosis.
=============================================

- I got a good squirt in my mouth
- I would imagine that there would be a large amount of involuntary gagging
- I don't know about you but I'm not into swallowing it

CCR discussion on Caustic Cocktails.
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Mateo1147
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Re: How common is deep air? NHZ

Post by Mateo1147 »

I agree with you 100% Bill. And no you didn't come within a mile of violating rule #1. So now the hard question. There are multiple opinions about max safe depth on air. Can everyone participating in this thread post their max depth on air and the logic give for said depth?
I will start. The only agency I have been trained through tells me that with air or the appropriate nitrox mix I am good to 130' so long as I stay within NDL. They do warn about narcosis being a safety hazard but don't seem to give it the weight I think they should.

Ok your turn..... :popcorn:
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Jeff Pack
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Re: How common is deep air? NHZ

Post by Jeff Pack »

200 long long ago, 184 last, although it's been so long I don't recall why that was.
=============================================

- I got a good squirt in my mouth
- I would imagine that there would be a large amount of involuntary gagging
- I don't know about you but I'm not into swallowing it

CCR discussion on Caustic Cocktails.
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GearHead
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Re: How common is deep air? NHZ

Post by GearHead »

During my training, we planned and executed dives from 40 to 42 meters using air as backgas and EAN50 as deco gas. This was in near ideal 80 - 80 conditions, and we still got narced to the point of missing a brief stop at 24 meters on one dive. With practice, 40 meter deco dives were pretty manageable.

In local PNW waters, I don't feel comfortable going much past 120' on Nitrox, and I haven't planned any deco dives below 110 feet. In cold dark water, the extra 10+ feet after 110 seem to make a big difference in my awareness and anxiety levels.
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BillZ
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Re: How common is deep air? NHZ

Post by BillZ »

I took Bob Baileys recreational deep diving class a few years back where we planned several dives in the 110 - 130 range. The class consisted of four dives to deep recreational depths which each dive progressively adding a bit more depth and task loading. We pretty much screwed up every drill we did at depth including getting hopelessly lost at 120ft in Cove 2. Needless to say after the class I decided that for me HE is a requirement past 110ft.
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Re: How common is deep air? NHZ

Post by Grateful Diver »

spatman wrote:
Waynne Fowler wrote:
spatman wrote:"slightrox"
:supz:

awesome word creation Spatz!
Wish I could take credit for it! I think I first heard it from Penopolypants many moons ago.
... she probably first heard it from me ... and I first heard it from Chris Jacobson at NWSD back in 2002 when I took my nitrox class ... and he probably heard it from someone back when they were still calling the stuff "voodoo gas" ... :rawlings:

... Bob (Grateful Diver)
Threats and ultimatums are never the best answer. Public humiliation via Photoshop is always better - airsix

Come visit me at http://www.nwgratefuldiver.com/
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pensacoladiver
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How common is deep air? NHZ

Post by pensacoladiver »

On open circuit, 140 was my max on air, in Florida. Up there it would be closer to 110.

As far as my logic, during my AN/DP/extended range training, I dove one day to 175 on the Hydro Atlantic and felt fine. I was actually thinking... This is easy shit

The very next day, we hit the Miller Lite, with a bit of current and by the time I hit 150, I was wasted to the point of almost panic.

I took a trimix class, started blending myself and never looked back.

I have no doubt that I could execute dives on air to 200 feet all day long... Right up until I can't. I certainly don't want to find that day.
Last edited by pensacoladiver on Sun May 04, 2014 5:59 pm, edited 1 time in total.
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Mateo1147
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Re: How common is deep air? NHZ

Post by Mateo1147 »

Jeff Pack wrote:200 long long ago, 184 last, although it's been so long I don't recall why that was.
I believe that if you calculate the PO2 of air you get 1.4 @ 184'. Probably were that particular depth came from.
Thank you to everyone who has chimed in with information. It is very valuable to me!
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Joshua Smith
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Re: How common is deep air? NHZ

Post by Joshua Smith »

I'll just say that I did lots of deep air dives before I got a re breather and trimix training. Not so much any more, but I wouldn't be worried about diving air to 130. Personal decision.
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Jeremy
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Re: How common is deep air? NHZ

Post by Jeremy »

We need a deep air emoticon
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ljjames
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Re: How common is deep air? NHZ

Post by ljjames »

There is a disturbance in the force...

A thread on NWDC discussing Deep Air Diving has not blown up in flames, tears, hurt feelings, and someone storm trooping off to bann'd camp ;)

Or perhaps just a glitch in the matrix...
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Re: How common is deep air? NHZ

Post by LCF »

From my OW training, I thought narcosis was like being drunk. When I'm drunk, I generally know it . .. I'm clumsy, I can't speak clearly, I may get emotional -- but I know I'm not normal. (Whether I'm ever normal is grounds for another discussion.). So I thought I would notice narcosis by being clumsy or confused or feeling fuzzy.

I don't. I don't know there is anything wrong with me, I just don't process information properly. I look at stuff and go, "Huh, that's interesting," and fail to recognize the import of what I have just seen. I am unsafe in that condition. I therefore absolutely hold myself to the 100 foot limit in open water (and rarely go that deep unless there is something specific I want to see) and 80 feet in caves, unless I have helium.
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Re: How common is deep air? NHZ

Post by GearHead »

Didn't I just see that same black cat a couple seconds ago? ;)

Made it down to 105 ft this morning in Cove 2. As we were working our way back up, my head cleared and I realized I had been a bit narced while floating giddily above the mermaid.

Narcosis is insidious. My next class is definitely going to be Trimix.
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Re: How common is deep air? NHZ

Post by spatman »

ljjames wrote:There is a disturbance in the force...

A thread on NWDC discussing Deep Air Diving has not blown up in flames, tears, hurt feelings, and someone storm trooping off to bann'd camp ;)

Or perhaps just a glitch in the matrix...
It's a kinder, gentler NWDC these days.
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Re: How common is deep air? NHZ

Post by Mateo1147 »

spatman wrote:
ljjames wrote:There is a disturbance in the force...

A thread on NWDC discussing Deep Air Diving has not blown up in flames, tears, hurt feelings, and someone storm trooping off to bann'd camp ;)

Or perhaps just a glitch in the matrix...
It's a kinder, gentler NWDC these days.
I'm still waiting for the other shoe to drop.......... :popcorn:
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Re: How common is deep air? NHZ

Post by johnclark »

On our trip to Truk Lagoon, the guides all dove air deep.
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spatman
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Re: How common is deep air? NHZ

Post by spatman »

Jeremy wrote:We need a deep air emoticon
:der:
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Re: How common is deep air? NHZ

Post by Jeremy »

lol, that should work
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kdupreez
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Re: How common is deep air? NHZ

Post by kdupreez »

before my GUE days, I"ve gone through the DSAT deep air training and regularly dropped to 160-170 on air without hesitation.. most of the time doing it solo..

My scare came the one day when I got back from a 170ft dive at Muk boat ramp and to my surprise, I discovered a Lacrosse ball in my pocket that I picked up somewhere along the line..After some self reflection, I could only muster a vague memory of picking it up… That was kinda the last days of deep air for me and I did DSAT trimix classes.

In my experience, helium makes a big difference, especially when task loaded.

the biggest enemy is actually CO2, not just Nitrogen.. When you start getting task loaded and work hard, your body produces CO2 thats 20x more narcotic than Nitrogen.. and guess what, the harder you work at depth, the faster you breathe "thick" gasses (air) and that work of breathing + exertion produces more CO2 and more CO2 means faster breathing.. that cycle rinses and repeats as you can imagine..

FYI - Pure Helium/Oxygen mix at 1,000 feet is as dense as Air or Nitrox at a mere 100ft.. go figure..

So bottom line, in my experience and opinion, helium on deeper dives is the price of admission.

Yes, $2k is a lot of money to drop on a Tec class, but its not just getting helium.. thats a byproduct.. You pay $2k for a technical diving and decompression diving class.. the helium cert is for free ;)
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60south
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Re: How common is deep air? NHZ

Post by 60south »

johnclark wrote:On our trip to Truk Lagoon, the guides all dove air deep.
There are many places around the world where air is the only option. When you're there, you have to make a decision about your personal limits and the safety of deep air, especially in a remote location.

On the wreck of the SS President Coolidge in Vanuatu, much of the diving is in the 150-220fsw range. After an air dive to 185ft I knew it was all way too deep and too dangerous for my comfort. So I stopped diving and instead did something far safer... climbed an active, lava-spewing volcano.

Locally, under ideal conditions, my limit on air is now 100fsw.
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