"Accidental" deco with 1-day group, what to learn?

[kalleth]

Thanks everyone for the thought out responses.

Here's what I've learnt:

1. It's my responsibility, even when diving with an instructor or divemaster, to monitor my own gauges and make my own decision if I'm uncomfortable to terminate the dive, not wait for the DM to do so, no matter how qualified they are compared to me.
2. When planning deeper dives, make sure I discuss what the turnaround points are on the surface, and that I'm not happy to go into deco -- my turnaround point is when I reach 1 minute remaining on my NDL, and I prebrief what signal I will give, so that everyone understands that on the surface.
3. I should take a nitrox course.
4. I'm considering buying a slightly less conservative computer -- not ridiculous like Shearwater but perhaps a Scubapro/Oceanic set to a slightly more conservative setting. I have to think about whether I'm comfortable with that first.

@DevonDiver I've sent a quick email to PADI so they know what happened. Mostly just my OP.

Thanks again!

 

[Basking Ridge Diver]

When planning deeper dives, make sure I discuss what the turnaround points are on the surface, and that I'm not happy to go into deco -- my turnaround point is when I reach 1 minute remaining on my NDL, and I prebrief what signal I will give, so that everyone understands that on the surface.

Why are you waiting on 1 minute remaining on NDL? What if you need 5 mins to square something away - buddy starts to panic, you need to get back to an anchor line? Seems like you are setting yourself up again...
Safe diving...

 

[Steve_C]

A few years ago I screwed up my Aeris by flooding it after I changed the battery. Ran next door and bought a ZOOP. Read the manual. Next day went out on a six pack for a double dip on the Spiegel. My first time diving it. Two of us divers and a guide. Did a dive (100 ft on air, pretty square profile). 1 hours SI and did dive 2. DM takes us on a swim through. I thought it was going to be real short but it turned out to be a couple minutes. During the swim through I notice that while I have plenty of air I am running real low on NDL. My options were limited. So I followed the guide out of the swim through. I am now about to hit zero. I have 3 options. a. Stay with guide and go into "deco". b. Make an assent into a raging current, avoid deco, and winding miles away in the ocean, c. Pointing to my computer and immediately swim across the deck to the assent line . I chose c. went slowly up the line and spent 15 minutes playing flag in a ripping current at 15ft.

Going into "deco" sometimes is not the worst choice you can make given the options.

 

[Caveeagle]

Going into "deco" sometimes is not the worst choice you can make given the options.

A few minutes of deco may not seem like that big of a deal, but what I think remains unsaid, is that you are now creating a virtual overhead situation. So, even if you are planning for a light 5m deco.. You need to be equipped to handle any gear failure without an emergency ascent. ie: full redundancy of gas supply, as well as a plan to hang on the anchor line or SMB and (hopefully) a crew looking out for you on the surface.

Modern computers can make deco seem like a piece-o-cake, but you are potentially opening up a whole new set of issues that you may not have prepared for. *I get that the OP is diving a super conservative computer, but IMHO, once you strap it on, you are now married to that logic, and should plan to follow it. Trying to mentally make adjustments is NOT a solid plan when 'IT' hits the fan.

 

[DevonDiver]

1. I'm considering buying a slightly less conservative computer -- not ridiculous like Shearwater but perhaps a Scubapro/Oceanic set to a slightly more conservative setting. I have to think about whether I'm comfortable with that first.

I'd suggest that first purchase should be something like 'Deco for Divers' by Mark Powell.

It's important that computer conservatism has no bearing on the physiological gas processes occurring in your actual body during a dive. If you dive longer... deeper... repetitively... over multiple days... then you're more at risk from DCS. Why would a computer display change your risk? Are you more safe because a computer says so? It changes anything?

Suunto RGBM isn't particularly conservative. It only becomes conservative if you abuse certain (safe diving) parameters. It adds conservatism for you... because you probably wouldn't do that for yourself... when you really should be.

If you want to do longer and longer dives... and not feel 'limited' by a computer... just dive with no computer. Dive as long as you want, as often as you want, with as little surface interval as you want.

Don't buy X, Y or Z computer because of what they "allow" you to do.... it's ludicrous.

Educate yourself on what you should be doing.... understand what...and why... the computer sets given parameters for your dives.

If unwilling to learn what's actually happening... abandon the quest for more aggressive diving. Stick with a conservative computer that will keep you out of trouble.

 

[kalleth]

Why are you waiting on 1 minute remaining on NDL? What if you need 5 mins to square something away - buddy starts to panic, you need to get back to an anchor line? Seems like you are setting yourself up again...
Safe diving...

I misspoke -- it obviously depends on the dive. If we're in open water and we can just "go up a bit", 1 or 2 minutes is probably fine. If we're in an overhead environment or planning a swim-through, I'd want to have more than that before we entered so I have margin when I come out. And so on

I'd suggest that first purchase should be something like 'Deco for Divers' by Mark Powell.

Thanks for the recommendation -- I'll add it to my reading list.

It's important that computer conservatism has no bearing on the physiological gas processes occurring in your actual body during a dive. If you dive longer... deeper... repetitively... over multiple days... then you're more at risk from DCS. Why would a computer display change your risk? Are you more safe because a computer says so? It changes anything?

Suunto RGBM isn't particularly conservative. It only becomes conservative if you abuse certain (safe diving) parameters. It adds conservatism for you... because you probably wouldn't do that for yourself... when you really should be.

This is one of the reasons cropping up as to why I'll stick with the Suunto, and all of this is a factor in the decision of whether to buy a less conservative computer -- it's a question of if I'm comfortable adding a slightly increased risk factor for DCS in exchange for more bottom time, with all of the questions that raises -- am I more or less at risk for DCS? What's my personal fitness level? Do I generally keep myself hydrated on dives? Can I control my buoyancy well enough in rental gear to make slow, controlled ascents? Am I better off diving a conservative computer on nitrox to give me that extra bottom time instead?

I don't think buying a less conservative computer changes my risk at all -- except to raise it, by increasing the time I spend accumulating nitrogen -- and your point is well taken.

 

[kablooey]

Kalleth, don't have tunnel vision thinking this is just about your choice of computer.
Sure, it's a factor, but also think about the part the lack of communication between you and the guide played in this scenario.
There are both technological and humanistic sides to diving. An appreciation of both will make you a better and safer diver, in my opinion.

 

[Colliam7]

It's absolutely, unforgivable, unprofessional and unethical dive supervision.

I am with you 100% on this one.

To the OP: I am glad that you have sent an email to the PADI office. Training agencies very seldom here about such non-training incidents directly from the diver involved. And, agencies have more than a little difficulty acting on information supplied by a third party, when the 'offending' dive operation denies that such a behavior occurred.

 

[kalleth]

Kalleth, don't have tunnel vision thinking this is just about your choice of computer.
Sure, it's a factor, but also think about the part the lack of communication between you and the guide played in this scenario.

I absolutely don't think this incident is about my computer; that's why that's a minor consideration and last on my list. Thanks for your concern

 

[redacted]

One minute later, my computer beeps, and I signal using my little finger (the sign we had agreed in the prebrief -- i've not been trained on it, as far as I can remember, but some googling says this is a 'deco' sign). The guide again "okays" me, and tells me to wait.

I thought the sign at that point was to extend the middle finger straight up as you begin your ascent.