5thD-X Ratio Deco "Mini" - Page 7

amascuba · October 26th, 2006, 09:40 PM

Quote: (Originally Posted by JeffG)

Call me crazy,

Ok. Crazy.

Janos · October 26th, 2006, 10:21 PM

Quote: (Originally Posted by Ahmed Adly, Marlin Inn DC)

No no. I would trust a Tech 1 certified person. But at the level I mentioned it really dose not matter if you spend an extra few minutes at depth. Basically at 45 minutes another 5 minutes would be just another 5 minutes deco.
So down to around 60 meters, things are really simple.

Sorry. I think it's a UK thing, but 45m scares the crap out of me!!! I'd assumed that you'd be Tech 1 to be doing those depths, but I'd forgotton about the Rec Triox course.

Janos

Ahmed Adly, Marlin Inn DC · October 26th, 2006, 11:02 PM

Quote: (Originally Posted by Janos)

Sorry. I think it's a UK thing, but 45m scares the crap out of me!!! I'd assumed that you'd be Tech 1 to be doing those depths, but I'd forgotton about the Rec Triox course.

Janos

Well Janos, you have to put things into perspective here. It would really depend on the team, weather, and so on. If I had a guy on his first deco dive to 45m, I would handle the matter differently than if I was doing a 45m dive with Hassan my brother.
I am actually suprised by how seriously I still take these matters

But really. 45m is not really all that bad. Maybe over there with the horrible diving conditions it might seem a bit "far away" down there. But I have some buddies who do 100 meters UNDER THE BLOODY ICE, not to mention in the bowels of an old sunken ship, in Sweden.

Ahmed

MonkSeal · October 27th, 2006, 12:46 AM

Quote: (Originally Posted by JeffG)

Awesome dive planning.

Call me crazy, but I (and the team) know how much deco and where before we descend. If we overstay our plan, then we have to adjust the deco.

Well, the subject here is ratio deco. So we're able to calculate our deco having in mind actual exposure. There's no need to discuss deco in details before dive if we're all on the same page. E.g. if we initialy plan to do 25 min at average 50 m at some wreck and then down there find out that lower deck is silty and go for something shallower making still 25 min but at average 42 m, does it make any sense to perform deco planned for 1st version? Or we decide to do 35 min at 42 m, or it's cold or we have emergency at half of planned BT and we want to go out, or whatever else? There are too many combinations of what can be done within the limits of gas we have and what can be changed to learn some deco plan by heart before dive. And still it's easy to calculate and shape deco.

JeffG · October 27th, 2006, 02:57 AM

Quote: (Originally Posted by MonkSeal)

Well, the subject here is ratio deco. So we're able to calculate our deco having in mind actual exposure. There's no need to discuss deco in details before dive if we're all on the same page. E.g. if we initialy plan to do 25 min at average 50 m at some wreck and then down there find out that lower deck is silty and go for something shallower making still 25 min but at average 42 m, does it make any sense to perform deco planned for 1st version? Or we decide to do 35 min at 42 m, or it's cold or we have emergency at half of planned BT and we want to go out, or whatever else? There are too many combinations of what can be done within the limits of gas we have and what can be changed to learn some deco plan by heart before dive. And still it's easy to calculate and shape deco.

I'm going to boil it down to English is a second language. We are not that far apart, but your details/description leave something to be desired.

*Hassan Adly* · October 27th, 2006, 03:27 AM

Hello,

Now the thread is mutating into a whole dive planning on the fly discussion - cool...

As long as the gas reserves, thermal considerations, oxygen tolerances, and practical time considerations are accounted for then having a very rigid runtime plan can be too limiting, especially when the team has a good feel for their individual member's factors such as SAC rates etc.

Once we know what the maximum/average depth will be, we can calculate our gas reserves, first for bottom gas, then for deco gasses. From this we can find out first what is the approximate time we can spend at depth, and what is the maximum deco time we can do without overstepping our deco gas reserves.

Once we have an idea of the limits, we know what envelope we have to work in, which in the 39m-60m range can be quite wide. As we get deeper or as the bottom times increase, the need for accuracy obviously increases, in all aspects of planning.

I don't think anybody is suggesting that thorough planning should be sacrificed in the name of flexibility - quite the opposite, by planning properly and learning to calculate on the fly effectively and reliably, we can do dives that are goal-oriented rather than built around the runtime plan.

MonkSeal · October 27th, 2006, 08:11 AM

Quote: (Originally Posted by Hassan Adly)

I don't think anybody is suggesting that thorough planning should be sacrificed in the name of flexibility - quite the opposite, by planning properly and learning to calculate on the fly effectively and reliably, we can do dives that are goal-oriented rather than built around the runtime plan.

Thanks Hassan, you precisely expressed what I was trying to.

*Clare* · October 29th, 2006, 10:12 PM

Amazing - a girl goes away for a while but the debates continue.

A wise old diver said to me recently (you have to be wise to be old in this game I feel) that it all works - to a greater or lesser extent - depends on your pain threshold really

Ratio Deco, linear deco, Bhulman, S curves, VPMB, 20/85, 10/120, deep stops at 2 atas - or 80 per cent - yadda yadda yadda.

I work my deco out in the water in all my diving - call it Ratio Deco if you like but all Ratio Deco represents is a pattern of numbers - as useful as any other pattern.

Read, dive, talk to others, inform yourself and then dive cautiously at first refecting on whether you are comfortable and asking yourself "truthfully" how you feel during and after the dive. Trust only the person who would be there to push your wheelchair to calculate your deco - otherwise make your own decisions. I've dived 10/130 profiles in the 60/70 range recently - but refused to dive other more conservative profiles when it felt wrong to do so. Patterns are just that - based on theroetical models which may or may not reflect your own needs.

Nothing down there worth dying for folks

October 26th, 2006, 10:21 PM	#62 (permalink)
Janos(Offline) "Two Sheds" Join Date: Nov 2005 Location: Surrey Posts: 412	Quote: (Originally Posted by Ahmed Adly, Marlin Inn DC) No no. I would trust a Tech 1 certified person. But at the level I mentioned it really dose not matter if you spend an extra few minutes at depth. Basically at 45 minutes another 5 minutes would be just another 5 minutes deco. So down to around 60 meters, things are really simple. Sorry. I think it's a UK thing, but 45m scares the crap out of me!!! I'd assumed that you'd be Tech 1 to be doing those depths, but I'd forgotton about the Rec Triox course. Janos __________________ You can lead a horse to water but you can't climb a ladder with a large bell in both hands - Vic Reeves DO of Hellfins

October 26th, 2006, 11:02 PM	#63 (permalink)
Ahmed Adly, Marlin Inn DC(Offline) New Member Join Date: Feb 2006 Location: hurghada Posts: 1,100	Quote: (Originally Posted by Janos) Sorry. I think it's a UK thing, but 45m scares the crap out of me!!! I'd assumed that you'd be Tech 1 to be doing those depths, but I'd forgotton about the Rec Triox course. Janos Well Janos, you have to put things into perspective here. It would really depend on the team, weather, and so on. If I had a guy on his first deco dive to 45m, I would handle the matter differently than if I was doing a 45m dive with Hassan my brother. I am actually suprised by how seriously I still take these matters But really. 45m is not really all that bad. Maybe over there with the horrible diving conditions it might seem a bit "far away" down there. But I have some buddies who do 100 meters UNDER THE BLOODY ICE, not to mention in the bowels of an old sunken ship, in Sweden. Ahmed __________________ Life and Death, although stemming from one another, seem to conflict as stages of change. Ahmed Adly, www.deepvoyage.com

October 27th, 2006, 03:27 AM	#66 (permalink)
Hassan Adly(Offline) GUE Instructor Join Date: Feb 2006 Location: Red Sea Posts: 336	Hello, Now the thread is mutating into a whole dive planning on the fly discussion - cool... As long as the gas reserves, thermal considerations, oxygen tolerances, and practical time considerations are accounted for then having a very rigid runtime plan can be too limiting, especially when the team has a good feel for their individual member's factors such as SAC rates etc. Once we know what the maximum/average depth will be, we can calculate our gas reserves, first for bottom gas, then for deco gasses. From this we can find out first what is the approximate time we can spend at depth, and what is the maximum deco time we can do without overstepping our deco gas reserves. Once we have an idea of the limits, we know what envelope we have to work in, which in the 39m-60m range can be quite wide. As we get deeper or as the bottom times increase, the need for accuracy obviously increases, in all aspects of planning. I don't think anybody is suggesting that thorough planning should be sacrificed in the name of flexibility - quite the opposite, by planning properly and learning to calculate on the fly effectively and reliably, we can do dives that are goal-oriented rather than built around the runtime plan. __________________ 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

October 29th, 2006, 10:12 PM	#68 (permalink)
Clare(Offline) GUE Instructor Site Admin Join Date: Nov 2005 Location: UK Posts: 1,930	Amazing - a girl goes away for a while but the debates continue. A wise old diver said to me recently (you have to be wise to be old in this game I feel) that it all works - to a greater or lesser extent - depends on your pain threshold really Ratio Deco, linear deco, Bhulman, S curves, VPMB, 20/85, 10/120, deep stops at 2 atas - or 80 per cent - yadda yadda yadda. I work my deco out in the water in all my diving - call it Ratio Deco if you like but all Ratio Deco represents is a pattern of numbers - as useful as any other pattern. Read, dive, talk to others, inform yourself and then dive cautiously at first refecting on whether you are comfortable and asking yourself "truthfully" how you feel during and after the dive. Trust only the person who would be there to push your wheelchair to calculate your deco - otherwise make your own decisions. I've dived 10/130 profiles in the 60/70 range recently - but refused to dive other more conservative profiles when it felt wrong to do so. Patterns are just that - based on theroetical models which may or may not reflect your own needs. Nothing down there worth dying for folks __________________ Clare . "Keep away from people who try to belittle your ambitions....Small people always do that, but the really great make you feel that you too can become great." Interested in DIR dive training? Always happy to chat/answer questions so get in touch via PM or visit www.dirdiver.co.uk

October 26th, 2006, 09:40 PM	#61 (permalink)
amascuba(Offline) New Member Join Date: May 2006 Location: West Texas Posts: 143	Quote: (Originally Posted by JeffG) Call me crazy, Ok. Crazy.

October 27th, 2006, 12:46 AM	#64 (permalink)
MonkSeal(Offline) New Member Join Date: Feb 2006 Location: Zagreb, Croatia Posts: 575	Quote: (Originally Posted by JeffG) Awesome dive planning. Call me crazy, but I (and the team) know how much deco and where before we descend. If we overstay our plan, then we have to adjust the deco. Well, the subject here is ratio deco. So we're able to calculate our deco having in mind actual exposure. There's no need to discuss deco in details before dive if we're all on the same page. E.g. if we initialy plan to do 25 min at average 50 m at some wreck and then down there find out that lower deck is silty and go for something shallower making still 25 min but at average 42 m, does it make any sense to perform deco planned for 1st version? Or we decide to do 35 min at 42 m, or it's cold or we have emergency at half of planned BT and we want to go out, or whatever else? There are too many combinations of what can be done within the limits of gas we have and what can be changed to learn some deco plan by heart before dive. And still it's easy to calculate and shape deco.

October 27th, 2006, 02:57 AM	#65 (permalink)
JeffG(Offline) New Member Join Date: Feb 2006 Location: Edmonton, Alberta Posts: 69	Quote: (Originally Posted by MonkSeal) Well, the subject here is ratio deco. So we're able to calculate our deco having in mind actual exposure. There's no need to discuss deco in details before dive if we're all on the same page. E.g. if we initialy plan to do 25 min at average 50 m at some wreck and then down there find out that lower deck is silty and go for something shallower making still 25 min but at average 42 m, does it make any sense to perform deco planned for 1st version? Or we decide to do 35 min at 42 m, or it's cold or we have emergency at half of planned BT and we want to go out, or whatever else? There are too many combinations of what can be done within the limits of gas we have and what can be changed to learn some deco plan by heart before dive. And still it's easy to calculate and shape deco. I'm going to boil it down to English is a second language. We are not that far apart, but your details/description leave something to be desired.

October 27th, 2006, 08:11 AM	#67 (permalink)
MonkSeal(Offline) New Member Join Date: Feb 2006 Location: Zagreb, Croatia Posts: 575	Quote: (Originally Posted by Hassan Adly) I don't think anybody is suggesting that thorough planning should be sacrificed in the name of flexibility - quite the opposite, by planning properly and learning to calculate on the fly effectively and reliably, we can do dives that are goal-oriented rather than built around the runtime plan. Thanks Hassan, you precisely expressed what I was trying to.