Safety stops

[Scuba_Vixen]

The statement that I said that in reply to was:



Nobody has yet explained how to do that. Soggy described a step-like approach that may be closer to it than the usual industry approach, but doesn't actually do it. The issue is whether there's enough benefit to outweigh the added complexity.

Holy Shinola there batman, if the arithmetic to figure a few half way points is complex, some one needs to seriously reconsider diving as a past time. Macrame sounds like a nice simple alternative.

While you probably don't notice a lot of difference after a single dive, curved ascent profiles really pay off for multi day, repetitive dives.

Anything that gets you out of the water cleaner is certainly a benefit.

 

[lamont]

If you're going to present made-up facts rather than true facts there's no point in continuing this discussion.

decaf.

 

[Snowbear]

P...In fact I haven't seen anyone in this thread complain about feeling bad after doing dives within the no-decompression lmits and using the industry standard approach. Why are so many folks having such vehement trouble with this?

Um... OK.... I'll start.....
Before I started using the much slower ascent profiles and paying attention to "shaping the curve," I would usually feel quite fatigued and sometimes even downright crappy after a dive or two near the "NDL" and using the industry standard 30fpm ascent rate and 3 min at 15'. Since I started changing the shape of my ascent curve, I actually find I sometimes feel better after the dive than I did before the dive!!

 

[pete340]

decaf.

No, just a bit more rest. <g>

 

[Soggy]

Are there any DIR instructors out there that want to jump in with a recommended ascent from 100'? I just can't believe that Soggy's method is "doing it right".

My profile is what is taught in a DIR Fundamentals class and is published in the supplemenal materials.

 

[StSomewhere]

The "natural curve" that Lamont refers to can be seen in just about any decompression program if you either enter a very agressive dive profile that generates deep required deco stops, or if you crank of the conservatism so high that deep stops are generated. You will also see the "faster at depth, slower and slower as you near the surface" curve if you use low gradient factors in a program that has that tweak.

What decompression programs are people using? Dive Voyager? VPlanner? Something else?

 

[lamont]

Um... OK.... I'll start.....
Before I started using the much slower ascent profiles and paying attention to "shaping the curve," I would usually feel quite fatigued and sometimes even downright crappy after a dive or two near the "NDL" and using the industry standard 30fpm ascent rate and 3 min at 15'. Since I started changing the shape of my ascent curve, I actually find I sometimes feel better after the dive than I did before the dive!!

I actually notice lack of alertness more than 'fatigue' and I feel kind of stoned if I'm bubbling too much (it actually kind of feels enjoyable). And yesterday I noticed its also a little hard to determine between the symptoms of 'bubble-fatigue' and the symptoms of excertion and low blood sugar -- except that after I ate I felt a lot better...

 

[Charlie99]

My profile is what is taught in a DIR Fundamentals class and is published in the supplemenal materials.

Your profile is a linear ascent, with the same amount of time spent at 10' and 20' as at 70' and 60' stops.

OTOH, the Minimum Deco Table by Peter Steinhoff at www.dir-diver.com show what, to me at least, appears to be a more rational and efficient set of stops:
40' 1 min
30' 1 min
20' 3 min
10' 3 min


You, however, not only say that your linear ascent is what you were taught in your DIR-F class and what is in the supplemental materials, but in reference to the dir-diver Minimum Deco tables, you have also posted "For the record, these tables are not DIR.

A review of Peter Steinhoff's profile here on Scubaboard shows that he is a member of WKPP, and in his posts he mentions completing Cave 1 and 2 with GUE instructor Dave Rhea.

It is very strange that he would be posting a table that is not DIR.

It is also very strange that you are being taught to use a linear ascent in your DIR-F class and material.

--------------

As I posted above, it would be nice if some GUE instructors could comment on Soggy's posts.

 

[Soggy]

You, however, not only say that your linear ascent is what you were taught in your DIR-F class and what is in the supplemental materials, but in reference to the dir-diver Minimum Deco tables, you have also posted "For the record, these tables are not DIR.

They are not considered the DIR approach to minimum deco, regardless of his affiliations, and that fact has been stated here by more than just me, I believe.

As I posted above, it would be nice if some GUE instructors could comment on Soggy's posts.

Contact Bob Sherwood, MHK, or BCS here on the board or on TDS. Good, bad, or indifferent, it's what I was taught. You don't have to like it. I am just explaining what I do. I've also stated that I usually add time at the shallower stops, especially on repetative dives.

I know some are still teaching to do a 30 ft/min ascent with pauses at every atmosphere up to 30 ft, where you do 1@30, 1@20, and 1@10. I'm not sure of why some are teaching one and others teaching the other, but either way, you end up with a similar profile on a 100ft dive.

What were you taught in your Fundies class?

 

[Soggy]

Here's what Vplanner has to say for 100' for 30 mins on 32%....

Dec to 100ft (2) on Nitrox 32.0, 50ft/min descent.
Level 100ft 28:00 (30) on Nitrox 32.0, 1.29 ppO2, 81ft ead
Asc to 10ft (33) on Nitrox 32.0, -30ft/min ascent.
Stop at 10ft 3:00 (36) on Nitrox 32.0, 0.42 ppO2, 4ft ead
Asc to sfc. (36) on Nitrox 32.0, -30ft/min ascent.

Off gassing starts at 57.1ft