GUE (and other non-PADI) Open Water Standards for No-Deco Limits

[eelnoraa]

... I can understand why GUE has an emphasis on procedure and deco discipline since using the table one would need it.

Bob, what would you call this table? NDL or deco? Keep in mind, the 100ft botton time is the same as the GUE min deco table. 100ft max time is 30min.

 

[Bob DBF]

NDL, however it is not a direct match to the GUE table, including the fact the ascent rate for the table is 30 fpm, not the 10 fpm that GUE uses. Also, from one of the posts, the GUE table is derived from the NOAA table, not PADI.

I am only assuming, which might be a stretch, that the profile @taimen is running what was said to be the algorithm that GUE is using. If you, or anyone, could run one that shows what is going on I would appreciate it.

I know from personal experience that I have run into deco by ascending too slow, that's a real trick the way I dive, and I think I was doing better than 10 fpm.

You have to understand that I am just trying to understand how the GUE system works, and am getting conflicting information from divers that purport to understand. I'll give it a rest and see if there is a definitive answer in the next 10 pages.


Bob

 

[taimen]

However, you are showing graphically why the GUE tables are not labeled NDL. I can understand why GUE has an emphasis on procedure and deco discipline since using the table one would need it.

GUE does a very good job in teaching how to safely dive using their table, using their protocols. Controlled ascents in all circumstances including emergencies are very much emphasized during the training from the beginning.

Rec I limit is 70', from one of the posts, and there may not be a ceiling under those conditions. If you could run that, at least I would be interested.

60 minutes at 70'/21m again gives you a tiny ceiling which is easily cleared with a min deco ascent.
Now I don't know for sure how the GUE table is derived. But it does follow the ceilings calculated with Buhlmann GF 20/85 quite well.

 

[Ayisha]

NDL does not mean that every dive is not a deco dive, it means there are No Decompression Limits to the dive...

The reason that people keep repeating the phrase to you, "Every Dive is a Deco Dive" is because that is the GUE philosophy. GUE does not believe there is such a thing as a dive with a "No Decompression Limit." We may bubble more or have more decompression stress on some dives than others, but we bubble or have some decompression stress on all dives.

NDL, however it is not a direct match to the GUE table, including the fact the ascent rate for the table is 30 fpm, not the 10 fpm that GUE uses...

30 fpm is to half the maximum depth (up to 100 feet), then 10 feet per minute to the surface. Example: On a 100 foot dive, 30 feet per minute to 50 feet, then 10 fpm to the surface.
On a 60 foot dive, 30 fpm to 30 feet, then 10 fpm to the surface.
Each 10 feet is a 30 second slide then 30 second pause for a very smooth profile.

 

[eelnoraa]

NDL, however it is not a direct match to the GUE table, including the fact the ascent rate for the table is 30 fpm, not the 10 fpm that GUE uses. Also, from one of the posts, the GUE table is derived from the NOAA table, not PADI.

I am only assuming, which might be a stretch, that the profile @taimen is running what was said to be the algorithm that GUE is using. If you, or anyone, could run one that shows Dwar is going on I would appreciate it.

I know from personal experience that I have run into deco by ascending too slow, that's a real trick the way I dive, and I think I was doing better than 10 fpm.

You have to understand that I am just trying to understand how the GUE system works, and am getting conflicting information from divers that purport to understand. I'll give it a rest and see if there is a definitive answer in the next 10 pages.


Bob

Take 100ft as example, two tables have the exact same bottom time, 30 min. If a diver following PADI table and for whatever reason he/she need to direct ascent, why the diver using GUE table can't do the same thing with the same level of safety or risk?

BTW, GUE recreation ascent profile isn't 10ft/min for all depth. For example, if you dive to 100ft, the profile is 30ft/min from 100ft to 50ft. Stay there for 1 min. Then do 10ft/min up to surface. What we usually do to realize 10ft/min is to spend 30 second on the ascent and 30 seconds at the target depth.

@Ayisha a beats me to it

 

[Storker]

I know from personal experience that I have run into deco by ascending too slow, that's a real trick the way I dive, and I think I was doing better than 10 fpm.

Yes, a slower ascent that your table prescribes may well increase your risk of DCS. If you ascend slower, there's a clear risk of ongassing during the ascent, and then the tables aren't really valid for your dive.

Our national tables assume an ascent rate of 10 m/min (33 fpm) from the bottom to the safety stop (or, if you're beyond the NDL, the deepest deco stop). 10 m/min is pretty darned fast, and I know from experience that you have to fin rather hard to keep that ascent rate if you're following a sloping bottom as you often might do on a shore dive.

 

[1atm]

With GUE fairly well covered ... what about other agencies? UTD? ISE? RAID? CMAS? ...?

 

[Storker]

With GUE fairly well covered ... what about other agencies? UTD? ISE? RAID? CMAS? ...?

CMAS has been mentioned:
GUE (and other non-PADI) Open Water Standards for No-Deco Limits
GUE (and other non-PADI) Open Water Standards for No-Deco Limits

Just remember that there are a lot of CMAS flavors. The certifying agencies are free to add to the syllabus and/or require more extensive abilities/skills than the minimum standard given by CMAS. I can only speak about the national CMAS certs awarded in my country, although the different Nordic CMAS syllabi are quite well coordinated.

 

[taimen]

Local CMAS federations can choose their own dive tables, and they really come in many flavors like my national diving associations RGBM derived tables.
Currently many tech divers (around me) favor profiles like GF30-50/70 and would probably plan also their 30 minute EAN32 dive to 100'/30m accordingly. Many recreational tables start to look quite aggressive if you compare them to NDL times derived from GF50/70.
I know it is very difficult to estimate how much the actual DCS risk changes. Thus ceilings and NDLs are just more or less arbitrary values.

 

[Storker]

Local CMAS federations can choose their own dive tables, and they really come in many flavors like my national diving associations RGBM derived tables.

Interesting. Can I ask you which Diving Association that is?