Min Deco/No Deco for Non-Tech Trained

GLOC · May 11th, 2006, 12:24 PM

During Fundies it was explained that until Tech trained, all the diving should be non-deco or rather Min Deco as every dive was a deco dive.

The parameters given were 1 min at 9m, 1 min at 6m and 1 min at 3m but no 'tables' were given other than 30mins and 30m is the base line and work back from there with 60 mins at 20m (Fundies Book).

Having done some research to find out more about Min Deco I have found some slightly conflicting information (it seems conflicting to me anyway). As many people have pointed out, there was no guidance in the old Fundies course about how to work out depth/time profiles without using a computer. Hence my questions.

The first set of info is from Peter Steinhoff with the Min Deco Table from 2003. This is quite a useful table in that is gives time/depth details, an ascent profile including stops and repetitive dive surface intervals. However, the stops are different 1@12, 1@9, 3@6, 3@3 but there is a deeper depth, 35m. It would be relatively easy to memorise the table and work from that but there is no guidance beyond the far right hand edge of the table which gives you 5 mins flex (for emergencies) but there is no guidance as to what to do beyond there other than 'padding the stops' but by how much.

Deleted all the bits about Ratio Deco as my assumptions were incorrect for a Min Deco dive from the 5thD paper (air limits rather than 32% or 30/30 although the 5thD paper does not say which gas is used on page 9 where it describes Min Deco). I also learnt that the depth/time limits that are used during the old Fundies was from the agency that you gained your original OW ticket with, which is why I don't remember being taught anything!!

I hope I am not getting out of my depth (pun not intended!), but I would
appreciate any feedback you may have with the points above. I am looking at doing Tech 1 at the end of the year once I have all the basic in-water skills nailed and am aware that the full gambit of RD will be taught then, but until then I would appreciate any info people have that can be used in the limits of Fundies, especially the GUE instructors.

Slightly linked to the above, in the new Fundies is this sort of thing going to be taught?

Regards

Gareth

Martin Burnard · May 11th, 2006, 12:30 PM

You have picked up on an area I have been looking at, in so much as the leap from Fundies to Tech 1 appears large, so how does one prepare.

Deco being one of the mysteries,
Preparing for line laying, snagging, lind ascents etc.

I guess you are trying the fore armed, is fore warned.

And on that issue, I am with you all the way!

*JohnKendall* · May 11th, 2006, 12:38 PM

Hi Gareth,

That looks like a lot too much deco for a 30min Dive to 30m on 32%.

Decoplanner on 30/85 GF gives:

9m: 1min
6m: 1min
3m: 2min

Personally I'd just do 3m/min from 15-surface for 30mins at 30m

HTH
J

GLOC · May 11th, 2006, 12:43 PM

Just had a brainstorm (thanks Clare) and realised that the figures I used were for air and not 32% and that is why they were off!! When I ran it they did seem much longer than I would expected even following the comments that we had!

Doh!

Oh well, sorry for being a burk! I will go back and redo them!! Which unfortunately takes it beyond the normal rec limits of 30m and 30mins.

Thanks for the interest!

**Alastair** · May 11th, 2006, 12:51 PM

Fundies didn't have time for any real time to be spent on deco theory - however Tech-1 does. In fact a lot of the discussion carried on into the evenings, the way Andy teaches courses you are learning from 8am - 11pm throughtout the course and the fact there are only 3 of you means you really do figure it out.

The advise I got after fundies was to do what you'd previously been doing - i.e. do whatever you've already been taught and that is certainly what I'd recommend to everyone!

Disclaimer aside - I did pick up the AG style method of 20mins at 30m being an NDL for an air dive. If you go 3m shallower then you get 5 more minutes up to cetain bigger leaps i.e:

Depth Time
12m 170 min
15m 60 min
18m 50 min
21m 35 min
24m 30 min
27m 25 min
30m 20 min
33m 15 min

At 75% of max depth you slow your ascent down for a brief pause, then begin 3m/min from 50% of your depth - this is often represented as 1min stops every 3m.

Bear in mind nitrox 32% gives you a -20% EAD so for a 30m dive you actually get 30mins NDL. This gives me a very easy way of working out a profile in my head. I also have a set of Bulhman tables in my wetnotes using 30/90 GF.

Oh and only do what you've been taught

Cheers
Al

GLOC · May 11th, 2006, 12:58 PM

Thanks Al, I have amended my original post and I am now in the process of cutting some tables from DP.

limeyx · May 13th, 2006, 06:32 AM

Quote: (Originally Posted by Alastair)

Fundies didn't have time for any real time to be spent on deco theory - however Tech-1 does. In fact a lot of the discussion carried on into the evenings, the way Andy teaches courses you are learning from 8am - 11pm throughtout the course and the fact there are only 3 of you means you really do figure it out.

The advise I got after fundies was to do what you'd previously been doing - i.e. do whatever you've already been taught and that is certainly what I'd recommend to everyone!

Disclaimer aside - I did pick up the AG style method of 20mins at 30m being an NDL for an air dive. If you go 3m shallower then you get 5 more minutes up to cetain bigger leaps i.e:

Depth Time
12m 170 min
15m 60 min
18m 50 min
21m 35 min
24m 30 min
27m 25 min
30m 20 min
33m 15 min

At 75% of max depth you slow your ascent down for a brief pause, then begin 3m/min from 50% of your depth - this is often represented as 1min stops every 3m.

Bear in mind nitrox 32% gives you a -20% EAD so for a 30m dive you actually get 30mins NDL. This gives me a very easy way of working out a profile in my head. I also have a set of Bulhman tables in my wetnotes using 30/90 GF.

Oh and only do what you've been taught

Cheers
Al

This is what I've been using as well, and it seems to work well and is easy to manage.

*Hassan Adly* · May 13th, 2006, 07:56 AM

Hello,

Min Deco is quite simple, and the rules as applicable to a fundies graduate are as follows:

1. Stay within established NDL's for Nitrox 32%
2. Ascend to 50% of maximum depth
3. Stop for 1 min. every 3 meters (stop time includes ascent to next stop)

Example profile:

30m 25'
15m 1'
12m 1'
9m 1'
6m 1'
3m 1'
surface

cmalinowski · May 17th, 2006, 11:17 PM

Quote: (Originally Posted by Hassan Adly)

Hello,

Min Deco is quite simple, and the rules as applicable to a fundies graduate are as follows:

1. Stay within established NDL's for Nitrox 32%
2. Ascend to 50% of maximum depth
3. Stop for 1 min. every 3 meters (stop time includes ascent to next stop)

Example profile:

30m 25'
15m 1'
12m 1'
9m 1'
6m 1'
3m 1'
surface

If you do a repetative dive, shouldn't you double the stops at some point on the second dive? Like 9m/2', 6m/2', 3m/2'

Chris

*Hassan Adly* · May 17th, 2006, 11:41 PM

Hello,

Yes, correct, for repetitive dives the procedure is:

1. min. surface interval of 60 mins
2. double shallow stops (9m, 6m, 3m) for conservatism

Keep in mind, however, that the above repetitive dive guidlines were made more for deco dives than for min. deco dives. It won't hurt to add the 3 extra minutes on the way up, but in most cases it will be overkill, very conservative.

I'll probably be crucified for this, but you could (shock, horror) use nitrox tables like the PADI 32% enriched air RDP to judge whether your repetitive dive is still in the NDL or min deco range.

Alternatively, for this type of diving you could use a nitrox computer like the suunto vyper or gekko, as long as you are within the NDL of the computer you can just do a standard min deco ascent.

May 11th, 2006, 12:24 PM	#1 (permalink)
GLOC (Online) Moderator Join Date: Nov 2005 Location: Fleet, Hants Posts: 1,963	Min Deco/No Deco for Non-Tech Trained During Fundies it was explained that until Tech trained, all the diving should be non-deco or rather Min Deco as every dive was a deco dive. The parameters given were 1 min at 9m, 1 min at 6m and 1 min at 3m but no 'tables' were given other than 30mins and 30m is the base line and work back from there with 60 mins at 20m (Fundies Book). Having done some research to find out more about Min Deco I have found some slightly conflicting information (it seems conflicting to me anyway). As many people have pointed out, there was no guidance in the old Fundies course about how to work out depth/time profiles without using a computer. Hence my questions. The first set of info is from Peter Steinhoff with the Min Deco Table from 2003. This is quite a useful table in that is gives time/depth details, an ascent profile including stops and repetitive dive surface intervals. However, the stops are different 1@12, 1@9, 3@6, 3@3 but there is a deeper depth, 35m. It would be relatively easy to memorise the table and work from that but there is no guidance beyond the far right hand edge of the table which gives you 5 mins flex (for emergencies) but there is no guidance as to what to do beyond there other than 'padding the stops' but by how much. Deleted all the bits about Ratio Deco as my assumptions were incorrect for a Min Deco dive from the 5thD paper (air limits rather than 32% or 30/30 although the 5thD paper does not say which gas is used on page 9 where it describes Min Deco). I also learnt that the depth/time limits that are used during the old Fundies was from the agency that you gained your original OW ticket with, which is why I don't remember being taught anything!! I hope I am not getting out of my depth (pun not intended!), but I would appreciate any feedback you may have with the points above. I am looking at doing Tech 1 at the end of the year once I have all the basic in-water skills nailed and am aware that the full gambit of RD will be taught then, but until then I would appreciate any info people have that can be used in the limits of Fundies, especially the GUE instructors. Slightly linked to the above, in the new Fundies is this sort of thing going to be taught? Regards Gareth __________________ Gareth Images of Life Photography DIR Team Foxturd Travels Underwater and Further Afar If you don't have the time to do something right, where are you going to find the time to fix it? - Stephen King Last edited by GLOC; May 11th, 2006 at 12:57 PM.

May 11th, 2006, 12:38 PM	#3 (permalink)
JohnKendall(Offline) GUE Instructor/DIRX Moderator Join Date: Nov 2005 Location: Cambridge, UK Posts: 1,100	Hi Gareth, That looks like a lot too much deco for a 30min Dive to 30m on 32%. Decoplanner on 30/85 GF gives: 9m: 1min 6m: 1min 3m: 2min Personally I'd just do 3m/min from 15-surface for 30mins at 30m HTH J __________________ John Kendall http://www.guetraining.com/ GUE Instruction, Santi and Halcyon Equipment NEW - Online Santi Shop

May 11th, 2006, 12:43 PM	#4 (permalink)
GLOC (Online) Moderator Join Date: Nov 2005 Location: Fleet, Hants Posts: 1,963	Just had a brainstorm (thanks Clare) and realised that the figures I used were for air and not 32% and that is why they were off!! When I ran it they did seem much longer than I would expected even following the comments that we had! Doh! Oh well, sorry for being a burk! I will go back and redo them!! Which unfortunately takes it beyond the normal rec limits of 30m and 30mins. Thanks for the interest! __________________ Gareth Images of Life Photography DIR Team Foxturd Travels Underwater and Further Afar If you don't have the time to do something right, where are you going to find the time to fix it? - Stephen King

May 11th, 2006, 12:51 PM	#5 (permalink)
Alastair(Offline) DIRX Supporter Join Date: Nov 2005 Location: UK Posts: 693	Fundies didn't have time for any real time to be spent on deco theory - however Tech-1 does. In fact a lot of the discussion carried on into the evenings, the way Andy teaches courses you are learning from 8am - 11pm throughtout the course and the fact there are only 3 of you means you really do figure it out. The advise I got after fundies was to do what you'd previously been doing - i.e. do whatever you've already been taught and that is certainly what I'd recommend to everyone! Disclaimer aside - I did pick up the AG style method of 20mins at 30m being an NDL for an air dive. If you go 3m shallower then you get 5 more minutes up to cetain bigger leaps i.e: Depth Time 12m 170 min 15m 60 min 18m 50 min 21m 35 min 24m 30 min 27m 25 min 30m 20 min 33m 15 min At 75% of max depth you slow your ascent down for a brief pause, then begin 3m/min from 50% of your depth - this is often represented as 1min stops every 3m. Bear in mind nitrox 32% gives you a -20% EAD so for a 30m dive you actually get 30mins NDL. This gives me a very easy way of working out a profile in my head. I also have a set of Bulhman tables in my wetnotes using 30/90 GF. Oh and only do what you've been taught Cheers Al __________________ Helium is our friend - GI3

May 11th, 2006, 12:58 PM	#6 (permalink)
GLOC (Online) Moderator Join Date: Nov 2005 Location: Fleet, Hants Posts: 1,963	Thanks Al, I have amended my original post and I am now in the process of cutting some tables from DP. __________________ Gareth Images of Life Photography DIR Team Foxturd Travels Underwater and Further Afar If you don't have the time to do something right, where are you going to find the time to fix it? - Stephen King Last edited by GLOC; May 11th, 2006 at 01:06 PM.

May 11th, 2006, 12:30 PM	#2 (permalink)
Martin Burnard(Offline) New Member Join Date: Nov 2005 Location: Plymouth, UK Posts: 580	You have picked up on an area I have been looking at, in so much as the leap from Fundies to Tech 1 appears large, so how does one prepare. Deco being one of the mysteries, Preparing for line laying, snagging, lind ascents etc. I guess you are trying the fore armed, is fore warned. And on that issue, I am with you all the way!

May 13th, 2006, 06:32 AM	#7 (permalink)
limeyx(Offline) New Member Join Date: Nov 2005 Location: Los Angeles, CA Posts: 708	Quote: (Originally Posted by Alastair) Fundies didn't have time for any real time to be spent on deco theory - however Tech-1 does. In fact a lot of the discussion carried on into the evenings, the way Andy teaches courses you are learning from 8am - 11pm throughtout the course and the fact there are only 3 of you means you really do figure it out. The advise I got after fundies was to do what you'd previously been doing - i.e. do whatever you've already been taught and that is certainly what I'd recommend to everyone! Disclaimer aside - I did pick up the AG style method of 20mins at 30m being an NDL for an air dive. If you go 3m shallower then you get 5 more minutes up to cetain bigger leaps i.e: Depth Time 12m 170 min 15m 60 min 18m 50 min 21m 35 min 24m 30 min 27m 25 min 30m 20 min 33m 15 min At 75% of max depth you slow your ascent down for a brief pause, then begin 3m/min from 50% of your depth - this is often represented as 1min stops every 3m. Bear in mind nitrox 32% gives you a -20% EAD so for a 30m dive you actually get 30mins NDL. This gives me a very easy way of working out a profile in my head. I also have a set of Bulhman tables in my wetnotes using 30/90 GF. Oh and only do what you've been taught Cheers Al This is what I've been using as well, and it seems to work well and is easy to manage.

May 13th, 2006, 07:56 AM	#8 (permalink)
Hassan Adly(Offline) GUE Instructor Join Date: Feb 2006 Location: Red Sea Posts: 287	Hello, Min Deco is quite simple, and the rules as applicable to a fundies graduate are as follows: 1. Stay within established NDL's for Nitrox 32% 2. Ascend to 50% of maximum depth 3. Stop for 1 min. every 3 meters (stop time includes ascent to next stop) Example profile: 30m 25' 15m 1' 12m 1' 9m 1' 6m 1' 3m 1' surface __________________ Hassan Adly Red Sea Discovery "Today I will finally see the sea again, which will smell of salt, wind, sand - and the cold of winter. Finally I will not only travel on it but dive in it, again I will become water, a bird - and I will remember the feeling of gliding above the abyss" Elena Sundukova, tragically lost at sea, January 2007

May 17th, 2006, 11:17 PM	#9 (permalink)
cmalinowski(Offline) New Member Join Date: Dec 2005 Location: Columbia, MD--USA Posts: 175	Quote: (Originally Posted by Hassan Adly) Hello, Min Deco is quite simple, and the rules as applicable to a fundies graduate are as follows: 1. Stay within established NDL's for Nitrox 32% 2. Ascend to 50% of maximum depth 3. Stop for 1 min. every 3 meters (stop time includes ascent to next stop) Example profile: 30m 25' 15m 1' 12m 1' 9m 1' 6m 1' 3m 1' surface If you do a repetative dive, shouldn't you double the stops at some point on the second dive? Like 9m/2', 6m/2', 3m/2' Chris

May 17th, 2006, 11:41 PM	#10 (permalink)
Hassan Adly(Offline) GUE Instructor Join Date: Feb 2006 Location: Red Sea Posts: 287	Hello, Yes, correct, for repetitive dives the procedure is: 1. min. surface interval of 60 mins 2. double shallow stops (9m, 6m, 3m) for conservatism Keep in mind, however, that the above repetitive dive guidlines were made more for deco dives than for min. deco dives. It won't hurt to add the 3 extra minutes on the way up, but in most cases it will be overkill, very conservative. I'll probably be crucified for this, but you could (shock, horror) use nitrox tables like the PADI 32% enriched air RDP to judge whether your repetitive dive is still in the NDL or min deco range. Alternatively, for this type of diving you could use a nitrox computer like the suunto vyper or gekko, as long as you are within the NDL of the computer you can just do a standard min deco ascent. __________________ Hassan Adly Red Sea Discovery "Today I will finally see the sea again, which will smell of salt, wind, sand - and the cold of winter. Finally I will not only travel on it but dive in it, again I will become water, a bird - and I will remember the feeling of gliding above the abyss" Elena Sundukova, tragically lost at sea, January 2007