"Riding your Computer Up" vs. "Lite Deco"

[stuartv]

Perhaps the real title of this thread should be:

"How to hack your dive computer to do more conservative safety stops after aggressive dive profiles".

Because, let's face it... we're not talking about committing to real, mandatory, decompression... are we?

Exactly! Finally!

 

[Lorenzoid]

Good instruction is an efficient way of acquiring knowledge and skills. Great instruction adds what you need to continue growing knowledge and skills without someone holding your hand. We are quite capable of recognizing our own shortfalls and taking appropriate actions.

We are capable of recognizing our own shortfalls and taking appropriate actions IF we survive. I would agree an instructor can't show a student EVERYTHING--some things need to be experienced and practiced. Also, progressively expanding one's comfort zone is a way of learning. On this specific topic of "deco lite," as what I might call a "serious" rec-only diver, I may or may not presently be in a position to try this--I just don't know and am not willing to risk experimenting with it when I know there are perfectly good courses out there to make sure I have checked all the boxes and am really ready to leave the nest and go out and practice on my own, such as Tec40 as Andy points out. I can use tables and dive planning software. I can calculate how much gas I need for any number of stops. I am getting better at holding stops every 10 feet. Still, it occurs to me that I don't know if I have thought of everything and if my skills are really at the required level. Why play with fire? Some of you have indeed figured out on your own what works for you, and that's great for you. However, I wouldn't encourage others to go down that path in order to extend their dives a few minutes beyond whatever "NDL" they are using.

Maybe AOW should be used for this sort of training. That is, tell divers "okay, so you learned in OW that the NDL is a bright line--and it was taught that way for your own safety as a new diver; now, in AOW we're going to teach you why that is not quite so, and teach you how to dive with that in mind." From what @KenGordon said, it sounds like BSAC Sport Diver does just that. Sounds like a very reasonable thing to me. It shouldn't be that controversial a topic--as evidenced by this long thread, it is--if taught in a sensible way.


By the way, what if we were to imagine a world in which the NDLs according to the tables and all available research were all just a few minutes shorter? Would rec diving not exist because people wouldn't think a mere 10 minutes looking at that wreck (instead of 15 minutes in our world) or 40 minutes cruising along that reef (instead of 60 minutes in our world) is worth the effort? Would more people be doing "deco lite" in order to extend their dives, so they could spend just five more minutes looking at that wreck? I don't think so. I think there would be just as many people who accept the limits as bright lines, and just as many people pushing the limits into "deco lite." In other words, no matter where one draws the line, there will always be people looking to exceed it slightly.

 

[uncfnp]

By the way, what if we were to imagine a world in which the NDLs according to the tables and all available research were all just a few minutes shorter? Would rec diving not exist because people wouldn't think a mere 10 minutes looking at that wreck (instead of 15 minutes in our world) or 40 minutes cruising along that reef (instead of 60 minutes in our world) is worth the effort? Would more people be doing "deco lite" in order to extend their dives, so they could spend just five more minutes looking at that wreck? I don't think so. I think there would be just as many people who accept the limits as bright lines, and just as many people pushing the limits into "deco lite." In other words, no matter where one draws the line, there will always be people looking to exceed it slightly.

Lite deco could be the new VooDoo gas.

 

[halocline]

Just do your aggressive bottom phase and voluntarily increase the duration and/or number of your safety stop/s to add as much extra conservatism as you'd like. Job done!

Yes....simple and efficient. This is recreational diving, after all.

 

[halocline]

Lite deco could be the new VooDoo gas.

Here's a bumper sticker version IMO:

Safety stops are 'lite' deco.

Recreational divers already do it, on most dives. The only practical difference would be to extend the safety stop longer in more aggressive dives.

 

[scubadada]

...So, for you recreational divers who do actually plan for and dive "light" deco: What do YOU consider the end of "light deco" to be?

For me, it is measured in minutes. 15...

I do light deco on about 5% of my dives. My average deco time is about 5 minutes, the range is 2-14 minutes. I generally extend the last stop several minutes, 3-5.

As with many controversial topics, this thread has wandered all over the place in it's 150 responses to the initial post. In some ways, this is good, many people are interested in the topic, seriously or casually. Some people know a lot about the topic, some, not so much. Some people have personal experience, some not. Many of the posts express strong feelings on the topic.

Clearly, the lack of a standard definition for light deco, has contributed to the variety of responses. I have always considered light deco to be an intentional, planned dive that exceeds NDL and results in a short deco obligation, satisfied with the single gas you are diving.

There has been considerable discussion on what NDL a diver chooses, aggressive or conservative, and the relationship to light deco. Rec divers choose their decompression algorithm(s) based on their own risk analysis. To me, this is not much different than technical divers choosing Buhlmann with certain GFs or VPM with specific conservatism to do their deco dives, nobody would say these are not deco dives. Personally, I think divers choosing to exceed their NDL in light deco, regardless of chosen algorithm, should simply satisfy the obligation. They can always change algorithms or adjust conservatism.

I've been doing light deco for about a decade within my own strict bounds and intend on continuing to do so. I do not have interest in extending my diving further into the technical realm and do not have any current plans for additional training.

I have enjoyed reading this thread and am glad @lowviz posted it. Good diving to all...

 

[redacted]

We are capable of recognizing our own shortfalls and taking appropriate actions IF we survive. I would agree an instructor can't show a student EVERYTHING--some things need to be experienced and practiced. Also, progressively expanding one's comfort zone is a way of learning. On this specific topic of "deco lite," as what I might call a "serious" rec-only diver, I may or may not presently be in a position to try this--I just don't know and am not willing to risk experimenting with it when I know there are perfectly good courses out there to make sure I have checked all the boxes and am really ready to leave the nest and go out and practice on my own, such as Tec40 as Andy points out. I can use tables and dive planning software. I can calculate how much gas I need for any number of stops. I am getting better at holding stops every 10 feet. Still, it occurs to me that I don't know if I have thought of everything and if my skills are really at the required level. Why play with fire? Some of you have indeed figured out on your own what works for you, and that's great for you. However, I wouldn't encourage others to go down that path in order to extend their dives a few minutes beyond whatever "NDL" they are using.

Maybe AOW should be used for this sort of training. That is, tell divers "okay, so you learned in OW that the NDL is a bright line--and it was taught that way for your own safety as a new diver; now, in AOW we're going to teach you why that is not quite so, and teach you how to dive with that in mind." From what @KenGordon said, it sounds like BSAC Sport Diver does just that. Sounds like a very reasonable thing to me. It shouldn't be that controversial a topic--as evidenced by this long thread, it is--if taught in a sensible way.


By the way, what if we were to imagine a world in which the NDLs according to the tables and all available research were all just a few minutes shorter? Would rec diving not exist because people wouldn't think a mere 10 minutes looking at that wreck (instead of 15 minutes in our world) or 40 minutes cruising along that reef (instead of 60 minutes in our world) is worth the effort? Would more people be doing "deco lite" in order to extend their dives, so they could spend just five more minutes looking at that wreck? I don't think so. I think there would be just as many people who accept the limits as bright lines, and just as many people pushing the limits into "deco lite." In other words, no matter where one draws the line, there will always be people looking to exceed it slightly.

I guess if the only other learning tool you have to work with is trial and error, that could be your situation.

Most folks have much more capability.

 

[Lorenzoid]

I guess if the only other learning tool you have to work with is trial and error, that could be your situation.

Most folks have much more capability.

Online forums? Books, most of which include specific disclaimers in the front cover that say this is no substitute for training?

 

[lowviz]

Yes. The BSAC Sports Diver course covers back gas deco. It is the qualification that almost all club divers will reach. ...//... The deco is back gas only, taught with tables. These are quite aggressive tables and educational in themselves. It includes altitude diving and particularly travel over hilly terrain. ...//... This training results in a different mindset to the AOW style training. Divers are not afraid of getting into deco. They have done stops in training, people do it regularly and they see them walk away. It is a tool which is available. ...

Just wow! Problem solved.

How is it the "Same dive profile, same dive", when one individual does deco stops and the other doesn't??

I overstated for the sole purpose of trying to get you to see that I'm only talking about the most aggressive of NDL dives as setting the limit for downtime. You kept dragging this discussion past anyone's NDL.

...//... The basis of the issue seems to that of 'disposable decompression'. That... because some table or algorithm exists somewhere that 'allows' a given depth/time as a no-stop dive... it therefore becomes an acceptable mindset to consider a deco plan as a cast-away option, rather than an obligation that the diver commits to. Genius...

Maybe you are starting to see the point.

No, one only casts-away the NDL part. One commits to the deco obligation.

Remind me... what name do we give to a non-mandatory stop performed for conservatism only?

Safety stop. Unless you get too close to your NDL, then it is a mandatory safety stop.

...//... What's suggested is really pointless. Just do your aggressive bottom phase and voluntarily increase the duration and/or number of your safety stop/s to add as much extra conservatism as you'd like. Job done! ...//...

Just make stuff up?

Why the compunction to fudge faux-deco? Because someone is unable to do something unless their computer 'tells' them to do it? You see how pathetic that sounds...?

You seem to have lost your ability to see things recreationally. Most recreational divers do exactly that. Are you implying that they are all pathetic compared to real tech divers?

Perhaps the real title of this thread should be:

"How to hack your dive computer to do more conservative safety stops after aggressive dive profiles".

Because, let's face it... we're not talking about committing to real, mandatory, decompression... are we? ...

Now I know that you finally comprehend the title of this thread.

...//... Surely if you're that experienced/serious/expert you can dive to the conservatism that you want, and follow your own ascent curve up?

Yeah, if I am willing to make stuff up. I'm not. I have my recreational hat on.

...//... And if you want to 'draw a conservatism line in the sand', then draw that line where you want it, and dive to it. Don't draw it somewhere and then totally disregard it by stepping over it. How far do you step over it?

I tried to make that clear. The agencies (that I have had contact with) draw that line, so do the PDC manufacturers. I don't make stuff up, the risk is too high for too many reasons IMHO.

...//... Maybe AOW should be used for this sort of training. That is, tell divers "okay, so you learned in OW that the NDL is a bright line--and it was taught that way for your own safety as a new diver; now, in AOW we're going to teach you why that is not quite so, and teach you how to dive with that in mind." From what @KenGordon said, it sounds like BSAC Sport Diver does just that. Sounds like a very reasonable thing to me. It shouldn't be that controversial a topic--as evidenced by this long thread, it is--if taught in a sensible way.

I couldn't agree more. I was previously unaware that BSAC taught this way.

...//... By the way, what if we were to imagine a world in which the NDLs according to the tables and all available research were all just a few minutes shorter? ...//... there will always be people looking to exceed it slightly.

It is my suspicion that most of this consternation is caused by divers with poor skills and high SAC rates having to end the dive before the rest of the group. It appears to me that a common kneejerk reaction to that humiliation is to find a more aggressive computer.

Lite deco could be the new VooDoo gas.

Thanks a bunch!

I suppose that makes me the new VooDooGasMan. Whatever happened to him? I miss him. He would have added value to this thread.

Here's a bumper sticker version IMO:

Safety stops are 'lite' deco.

Recreational divers already do it, on most dives. The only practical difference would be to extend the safety stop longer in more aggressive dives.

How does one do that? Follow a recommended procedure or just make stuff up?

 

[DevonDiver]

Just make stuff up?

You seem to have lost your ability to see things recreationally. Most recreational divers do exactly that. Are you implying that they are all pathetic compared to real tech divers?

Yes... it's a safety stop. So just make it up. It's a simple over-stay in the shallows to permit additional gas diffusion.

Why would you need to 'hack' your dive computer... in the process losing your real-time awareness... to do an extended safety stop?

What seems pathetic is that divers gave become so reliant on their computers talking them what to do... they'd rather fudge the computer than just add a few minutes, or whatever, when they're otherwise cleared to surface.

What's pathetic is the over-complication of such a ridiculously simple protocol, just to satisfy some inane addiction to seeing numerals on a screen.

Talk about 'overthinking' things...

The drawback to these faux-deco shenanigans is that it can incite complacency over no-stop limits... the diver is never quite sure of exactly what they have to do... versus the imaginary stuff.

Kind of a getting-bent version of the 'boy who cried wolf'.