New NAUI safety stops

[tbrown]

I was reading an article on how Naui was changing it's saftey stops for dives over 40 ft. Instead of a 3 minute @15ft, it's 1 minute @ 1/2 the deepest part of the dive, and 2 minutes @ 15 ft. While this seems like an interesting idea, the article was rather a short one, and I was wondering if anyone else had heard about this, and more importantly had a more in-depth article.

[DRE]

TBROWN,

could you please post a link or reference to the article. It seems to me NAUI is starting to incorporate some of the DIR/VPM thoughts on decompression in their curriculum. I think this is a great idea and divers who are doing "no-deco" dives will definitely start feeling better after doing the deeper stops.
There's an interesting article by Eric Baker on deep stops - you can find it at several places, but the one I know of the top of my head is at , go to 'bibliotheek' and scroll down to articles. Also, on there are some articles by GI3 on doing decompression, which will give you some more insight in why to do those deeper stops. Also, check out , which is a site dedicated to the VPM deco model.

[Freedive WI]

NAUI has added quite a few really good things to their program. They are now using the RGBM tables for their tec dives. Their tec diver curriculum actually has a lot of DIR things in it. I like it much better than the PADI and TDI stuff.

I have looked at some of the NAUI tables, for trimix, and run the numbers on them as compared to my Decoplanner program from GUE. The numbers came out almost excatly the same. The NAUI tables allowed for a wide variety of helium mixes, but were all configured as if it were the highest helium content listed was used in the Decoplanner program.

On a dive deeper than 40' I no longer do 3 minutes at 15'. I now do 1 minute at 30', 1 minute at 20' and 1 minute at 10'. The slower ascent rates make a big difference in bubble size and post dive fatigue.

You can also look up some of Dr Richard Pyle's earlier work on deep stops and some of Dr. Bruce Wienke's more recent work on RGBM models.

Jon

[ccuda]

Check into DAN's research, I believe last year they published and intensive study of physiological theories of off-gasing with deep stops versus the typical safety stop for recreational diving. It was a great eye opener and Kim's theory of only needing the 15ft safety stops was disproven beyond a doubt. DAN has been consistant in their research for diver's physiology in which all the other agencies then adopt into their training proceedures. I find it of great value to check the DAN website often. Also, being a member provides you with the quarterly newletter, as you will find many great insights into diver behavior and risk factors. (It's more up to date with recent developments and you'll find it the info there before the training agencies put it in their literature.)

DAN is the authority on scuba diving safety, physiology studies, and research. Their website is

[ccuda]

And Jon is right, making a slow and conscienscious ascent rate makes a BIG difference!

Something you'll also find at WKPP is their discussion on PFO and their experience of bends on bounces for retreival of stage bottles after deco dives. They were bending divemasters who went to pick them up at 20ft after the long 10ft stops. Interesting read and useful to the recreational diver dipping down after a stop.

Also, not blowing to the surface after the 15-10ft stop makes a big difference. I see alot of recreational divers think the dive is over and forget about their ascent rates from their shallow safety to the surface. Keep it REALLY slow, there's no rush.

[chrisw]

Maybe someone at Smith Diving could give us more
on the NAUI reasoning/perspective?

[Freedive WI]

Ccuda is right about not "bouncing" back down to grab something off of the bottom, like a deco bottle. Many people have bent themselves after doing just that. They came up from the dive clean, bounced back down, and when they came back up- bent like a pretzel. :-[


This is also very important when it comes to mixing freediving with scuba diving. You can freedive all you want and THEN go scuba diving. If you go scuba diving first and then try to go freediving you can end up bent very quickly. I have heard of this happening many, many times.

Always remember to freedive BEFORE your scuba dives and never after.

Jon

[LKunze]

Yes, also if I am not mistaken I believe cdtgray is a NAUI instructor as well.

[tbrown]

DRE- I read the article in this months DIVE TRAINING. It did not really go into it too much, mostly a byline. I read about it on the net a few months ago, but I have it at work, not home. I'll post the link when I can. It was a little bit more in depth, but it was only a summary of the presentation that was given this year in Tampa by Dr. Weinke and Timothy O'Leary. And yes there was a nice big sideline by GI3 stating "Everyone is finally figuring out what we have been doing for years" Actually it seemed they spent more time on his comments than giving the details of the paper, but GI3 does get ink.

ccuda- thanks for the DAN link. I don't know why that wasn't the first place I thought of, as you are correct, for physics/physiology, they are a great source.

[SmithDiving]

First let me say I won’t try to explain any deco. theory here, (You’ll have to come & take the NAUI Master Diver course).
Some divers have been doing deep stops since at least the late 80’s. I suspect that a lot of divers actually had been doing them for decades prior to that without realizing it. When divers spearfish in deep water they tend to create an inadvertent deep stop where they catch their fish. This is actually what got Richard Pyle thinking about the idea of deep stops.
The NAUI Technical Diving Workshop this winter was entitled “Deep Stops and Modern Decompression Strategies”. The workshop was co-chaired by Tim O’Leary, Director of Technical Diving Operations for NAUI and Bruce Wienke from Los Alamos National Laboratory. The workshop was attended by more than 100 people representing numerous training agencies and diving specialties. I thought about attending this year, but as I have attended several presentations in the past by Dr. Wienke, I knew I would be lost in a very short time, (these guys are scary smart).
The new NAUI recommendation for deep stops is as stated in the earlier replies – For dives deeper than 40’, halve the depth of the dive and make a 1 minute stop at the halfway point to the surface, then stop at 15’ for 2 minutes. As a rule on any “Smith Diving” class dives we have been doing 3 minute precautionary stops at 15’ on any dive in excess of 30’. We will now be changing that practice to reflect the new deep stop requirements. We have had some debate about this regarding dives in the 45-60’ range (you may end up doing a stop at 22’ and then again at 15’). But, as with all things NAUI, better safe than sorry. We are very grateful that there are leaders out there doing the kind of work that helps keep us all safe and continues to reduce the risk of DCS. I am including a link to a great article by Richard Pyle, one of the Workshop contributors. It was first published in DeepTech and again later in The Cave Diving Group Newsletter.
Richard Pyle's article references some very good information, including another article by Dr. Bruce Wienke which is really complex but is worth the effort. Here’s the link:

Deco theory is one of the most interesting aspects of diving physiology and we will have lots of fun with this “new” practice in our future classes.