Safety stops when monitoring SurGF

[EFX]

L

Last diver to 30 bar wins!

Don't you mean last diver to the bar loses. What's this 30 stuff?

 

[boulderjohn]

1. the original poster should not be putting much numerical importance in their precise "Surface GF" number on a dive with no explicit deco stops, and should just stick to the basic idea of a shallow pause period in their ascent for safety, and/or a very slow ascent rate while surfacing.

What is wrong with using the SurfGF as a guide? You seem to be saying they should instead stick to the "basic idea of a shallow pause" of unspecified length on all dives. And then in the next point...

2. nor should the original poster be confident that any completely arbitrary prescription of "X minutes at X metres/feet" during rec dives is proven to be specifically ideal for DCS avoidance

you contradict the previous one, telling divers that, well, I honestly don't know what you are telling them.

The "3 mins @ 5 metres/15 feet" thing is mostly an industry crowd control technique to train customers. Any number of minutes at any shallow depth is probably helpful, though not required for everyone, nor completely protective for those already prone to DCS that day.

So the standard safety stop is "an industry crowd control technique to train customers," even though it has been recommended by nearly all agencies for decades following the publication of a study done before that time. Instead, you recommend two 3-minute stops, one at 20 feet and one at 10 feet. I asked for the research behind that, and you did not give it.

I have read your posts repeatedly, and I cannot figure out what you are actually saying. I must be losing my reading ability in my old age. It almost seems like you are saying nothing works for certain, so just wing it. Do a pause of unspecified length in shallow water, head for the surface, and hope for the best.

 

[tursiops]

The "3 mins @ 5 metres/15 feet" thing is mostly an industry crowd control technique to train customers. Any number of minutes at any shallow depth is probably helpful, though not required for everyone, nor completely protective for those already prone to DCS that day.

Please read Info - History of the Safety Stop and see if you still think the Safety Stop is an industry crowd control technique. Unfortunately the Rubicon links in that article are no longer valid, but I have downloaded pdfs if you want them.

 

[grantmac]

Did some dives yesterday with the Clear now active and can confirm that on dives within the NDL as soon as I reached 20ft it started counting up, hence can be used to time your safety stops. As I have my last stop set to 20ft, I am not sure if the last stop was set to 10ft that it will not start counting unless you are at 10ft.

I have last stop set to 3m and it began counting up at 6m today in OC tec mode today.

 

[admikar]

Frankly, if you want to get out of the water three minutes faster then why did you bother spending the other 57 minutes (or whatever) in the water at all? This is the sort of lazy corner cutting that gets people in trouble.

What kind of question is that?
Frankly, if you are not doing 150 200 300 minutes dive, why did you bother getting into the water in the first place?
This is technical diving section, people reading here should have an understanding of what is said and why.

And I totally agree with another poster that it is either NDL diving or safety stops are mandatory. Not both.
Yes, safety stops are benefitial, but please let's stop trying to get to "you are going to die!" narative level.
We have enough of that coming from agencies that are just trying to cover their behinds due to people losing ability/refusing to take personal responsibility for themselves.

 

[admikar]

L

Last diver to 30 bar wins!

30 bars?! Wuss!

 

[scubadada]

30 bars?! Wuss!

Now that is sucking down your gas

 

[bubblemonkey2]

What is wrong with using the SurfGF as a guide? You seem to be saying they should instead stick to the "basic idea of a shallow pause" of unspecified length on all dives. And then in the next point...

you contradict the previous one, telling divers that, well, I honestly don't know what you are telling them.

So the standard safety stop is "an industry crowd control technique to train customers," even though it has been recommended by nearly all agencies for decades following the publication of a study done before that time. Instead, you recommend two 3-minute stops, one at 20 feet and one at 10 feet. I asked for the research behind that, and you did not give it.

I have read your posts repeatedly, and I cannot figure out what you are actually saying. I must be losing my reading ability in my old age. It almost seems like you are saying nothing works for certain, so just wing it. Do a pause of unspecified length in shallow water, head for the surface, and hope for the best.

Yes, unfortunately actual personalized decompression is very much still a black art, which is clearly evident in so many anecdotal stories of "but I did my PADI safety stops and still got bent"

It is vague, it is uncertain, and this is unsatisfying. I agree with you!

So for "NDL" diving sure, ascend at 3 metres/10 feet per minute or less above half your max depth, and take some extra time to regroup, tidy up, and communicate somewhere between 6 and 3 metres.

Go ahead and do the PADI stop if that's what your team agreed to, because there are several safety features of doing so--notably crowd control and surface hazards. But it is probably no more important for DCS than simply ascending and surfacing slowly.

That's as clear as it gets I think.

To properly science this, we would need something directly measurable for personalized decompression, such as a high quality consumer submersible doppler, deployed into the wild and gathering realtime data for thousands of people's dives. Then gather all that in-water data together and look to see if there is something, anything in there that reliably and predictably links a measurable value to DCS occurrences. Someone please invest $50 million to make it happen

 

[TheCatFish]

Yes, unfortunately actual personalized decompression is very much still a black art, which is clearly evident in so many anecdotal stories of "but I did my PADI safety stops and still got bent"

It is vague, it is uncertain, and this is unsatisfying. I agree with you!

So for "NDL" diving sure, ascend at 3 metres/10 feet per minute or less above half your max depth, and take some extra time to regroup, tidy up, and communicate somewhere between 6 and 3 metres.

Go ahead and do the PADI stop if that's what your team agreed to, because there are several safety features of doing so--notably crowd control and surface hazards. But it is probably no more important for DCS than simply ascending and surfacing slowly.

That's as clear as it gets I think.

To properly science this, we would need something directly measurable for personalized decompression, such as a high quality consumer submersible doppler, deployed into the wild and gathering realtime data for thousands of people's dives. Then gather all that in-water data together and look to see if there is something, anything in there that reliably and predictably links a measurable value to DCS occurrences. Someone please invest $50 million to make it happen

Although it doesn't work in real-time, the ODIVE personal dopplar is a pretty cool piece of tech. Couldn't help name dropping it after reading your comment about personalized safety profiles.

 

[grantmac]

Purely anecdotal but I definitely feel less post-dive fatigue with a longer stop on NDL dives.
I'm diving in an area with quite a bit to look at shallow so I find myself happily looking at nudibranches until I'm too cold or have to pee. The days I shorten that to just a slow ascent I can feel it.

I learned in an environment (military) where shallow dives, high exertion and direct ascents are the norm: post dive fatigue was massive (could have been the non-stop PT as well).