Feedback on recent two-tank and dive limits

[inquis]

Good reminder to refresh myself on the basics of dive planning rather than relying too much on my computer

One big reason computers are popular is they deal with multi-level profiles extremely well. If you had tried to plan your dive based on a square profile at max depth, your allowable bottom time would have been quite short. You could dive that reduced time, but why would you?

Personally, I'd say a better reminder would be to pay MORE attention to your dive computer, rather than to rely less upon it. It is a far better tool for the type of diving you're doing compared to the "basic planning" that you can realistically do.

 

[lizzzzz]

Therein lies your issue as to why the NDL was at one point 1 minute. All other setting aside, 35 minutes is a short surface interval. Why the rush to get back in the water?

Most divers plan for a 1 hour surface interval. Why? besides being a round number, it gives many tissues just enough time that the loading on the second dive does not run into a NDL. Even if diving to a similar depth.

Oh absolutely. And it was a situation where the dive guides rushed everyone in and I just didn’t clock the time. I have some questions about the guides in general, since when we arrived they were going to take some discover scuba folks on a 100’ wreck dive (which I learned later).

But definitely on me for 1) not keeping track of the SI, and 2) not insisting on more boat time when they rushed everyone back in for dive #2. Won’t do it again.

 

[lizzzzz]

One big reason computers are popular is they deal with multi-level profiles extremely well. If you had tried to plan your dive based on a square profile at max depth, your allowable bottom time would have been quite short. You could dive that reduced time, but why would you?

Personally, I'd say a better reminder would be to pay MORE attention to your dive computer, rather than to rely less upon it. It is a far better tool for the type of diving you're doing compared to the "basic planning" that you can realistically do.

Agree and I typically pay very close attention to it. Definitely a case of multiple dive variables (low and changing viz combined with shifting currents, easily the most challenging dive my son has done) distracting me in a way I haven’t had before.

I’m not saying I want to rely less on the computer, but that I want to revisit my basics (tables, GF, etc) to help better understand the “why” behind the computer. So I won’t have to ask questions like this that I should know myself, essentially

I really do appreciate the feedback and am super grateful for everyone’s responses.

 

[johndiver999]

Thanks, all! I hadn’t had this happen before even with deeper depths, but it’s perfectly possible I shifted my computer settings since then because it’s been a few years. (I’ve been diving with my son since last year, so much shallower and easier than previous years with friends.) I revisited the tables but wanted to check with folks here, since you all are a wealth of knowledge.

I think my biggest lesson is that I’m not ready to be in more challenging conditions with my kiddo-as-buddy. He had a great dive, but it made me a touch more anxious than needed. Good reminder to refresh myself on the basics of dive planning rather than relying too much on my computer - for my own peace of mind as much as anything else. Thanks again!

YES, a good lesson. Diving with someone who you are responsible for (and who you know is potentially challenged by the upcoming dive) is (or can be) extremely distracting. It is much easier to dive solo than when you have a buddy like that. I am much more likely to make mistakes when gearing up and also during the dive when I place too much concentration on the buddy and not enough on myself and the dive.

 

[lizzzzz]

yup

This feels like the answer ^^^

I’m not familiar with how gradient factors work and am sure I would have been less concerned if I was. Not sure if it’s me not remembering from my dive training, that OW and AOW courses didn’t go into it in detail, or both. Either way, it’s on me to learn now. Thanks for this

 

[Divin'Papaw]

I’m not saying I want to rely less on the computer, but that I want to revisit my basics (tables, GF, etc) to help better understand the “why” behind the computer. So I won’t have to ask questions like this that I should know myself, essentially

I really do appreciate the feedback and am super grateful for everyone’s responses.

Here are a few articles I’ve found helpful:

Gradient Factors - Dive Rite | Equipment for Serious Divers

Remember your first diving classes and the lesson about bubbling soda bottle and too rapid ascents? No matter how deeply you study the decompression theory, this soda bubble analogy is still valid. However, it’s time to introduce some more fundamentals of the issue. But let’s start from the...

diverite.com

Gradient Factors in a Post-Deep Stops World

World-recognized decompression physiologist and cave explorer David Doolette explains the new evidence-based findings on “deep stops,” and shares how and why he sets his own gradient factors. His recommendations may give you pause to stop (shallower).

indepthmag.com

Flexible Control of Decompression Stress

Divers who understand the inherent uncertainty in decompression modeling and want to take a more active role in their own dive planning can use available tools to tailor the limits to their needs or preferences. This is a good choice for dynamic conditions or complex dives, when the goal of...

shearwater.com

Gradient Factors Can Be Used To Control For Depth-Time Exposure And Alleviate The Risk of Decompression Sickness In Recreational Diving

The dive profile may be the key in figuring out why some dives result in decompression sickness and others do not.

dan.org

Gradient Factors

While dive computers are helpful, they are limited in predicting decompression stress. Read more about the limitations of dive computers.

dan.org

 

[lizzzzz]

YES, a good lesson. Diving with someone who you are responsible for (and who you know is potentially challenged by the upcoming dive) is (or can be) extremely distracting. It is much easier to dive solo than when you have a buddy like that. I am much more likely to make mistakes when gearing up and also during the dive when I place too much concentration on the buddy and not enough on myself and the dive.

Absolutely. I have a different mindset diving with my son than, say, friends or other adult buddies. Until yesterday I thought it made me more cautious, but I’m realizing I wasn’t necessarily cautious about the right things. Ironically, he’s turning into a fantastic junior diver so my worries are largely misplaced. He’s actually the one who flagged the SI and I used it as a lesson that he’s my equal underwater and I’m relying on him to clock things I might miss. But great caution on missing things in gear check - I could imagine being so focused on him I might goof on myself.

 

[lizzzzz]

Here are a few articles I’ve found helpful:

Gradient Factors - Dive Rite | Equipment for Serious Divers

Remember your first diving classes and the lesson about bubbling soda bottle and too rapid ascents? No matter how deeply you study the decompression theory, this soda bubble analogy is still valid. However, it’s time to introduce some more fundamentals of the issue. But let’s start from the...

diverite.com

Gradient Factors in a Post-Deep Stops World

World-recognized decompression physiologist and cave explorer David Doolette explains the new evidence-based findings on “deep stops,” and shares how and why he sets his own gradient factors. His recommendations may give you pause to stop (shallower).

indepthmag.com

Flexible Control of Decompression Stress

Divers who understand the inherent uncertainty in decompression modeling and want to take a more active role in their own dive planning can use available tools to tailor the limits to their needs or preferences. This is a good choice for dynamic conditions or complex dives, when the goal of...

shearwater.com

Gradient Factors Can Be Used To Control For Depth-Time Exposure And Alleviate The Risk of Decompression Sickness In Recreational Diving

The dive profile may be the key in figuring out why some dives result in decompression sickness and others do not.

dan.org

Gradient Factors

While dive computers are helpful, they are limited in predicting decompression stress. Read more about the limitations of dive computers.

dan.org

Amazing, thank you!

 

[34109411]

This feels like the answer ^^^

I’m not familiar with how gradient factors work and am sure I would have been less concerned if I was. Not sure if it’s me not remembering from my dive training, that OW and AOW courses didn’t go into it in detail, or both. Either way, it’s on me to learn now. Thanks for this

Yup in adaptative it will give you a safety like the previous post mention.

I suggest you read the manual in detail for the sherwater, everything is well described. Also check you tube penty of video will explain you what are the gradient factors. OW or AOW don't cover this cause because it's computer related and every brand out there is different.

Be safe

 

[lizzzzz]

Appreciate it