Tech1 Ratio Deco - Explained

[David]

I was chatting to Garf about RD and made this comment.
" even when some muppet says through the round window Ill have Ham and Pinnapple please its all Garfs fault im here"


David

[GLOC]

Originally Posted by David

I was chatting to Garf about RD and made this comment.
" even when some muppet says through the round window Ill have Ham and Pinnapple please its all Garfs fault im here"


David

No, you're in a pot!

[IanDennis]

Garf

Thanks for putting this up - it removes some of the mystic around the subject.

For interest its very relevant but as you said only a idiot would go and do this without training. I intend to stick with my VR3 for the time being until fundies and Tech 1 is out the way. Then maybe give it a try

Many thanks

Ian

[Ant P]

Just a quick question on the side really, Garf. In your team, when a member is tasked with 'running the deco' for the team - what do they communicate? Do they announce the total deco when the bag is shot and the length of each individual stop at each stop or what?

And what happens if one of the members of the team has a different average depth from the other team members. Does this change who is chosen to calculate the deco?

Just curious like,

Cheers, Ant

[Garf]

Originally Posted by Ant P

Just a quick question on the side really, Garf. In your team, when a member is tasked with 'running the deco' for the team - what do they communicate? Do they announce the total deco when the bag is shot and the length of each individual stop at each stop or what?

And what happens if one of the members of the team has a different average depth from the other team members. Does this change who is chosen to calculate the deco?

Just curious like,

Cheers, Ant

When we move to the 18m stop then we say how long we are staying there for. If we are rounding up the deco to the nearest 10 mins then thats the only signal you need. you now know how long each stop is going to be in the intermediate stops and how long the stop will be at 6M

Remember that we have 5 equal stops, and then the same again at 6 metres. so that means we can multiply whatever signal we are given at 18 metres by 10 and we know how much deco we have. 4 minute stop called, 40 mins deco to do. We know we are gonna have to do 4 at 15, 4 at 12, 4 at 9 and 20 at 6. Simple.

If we are not doing the rounding up thing becuase, well for whatever reason, then at each stop the person calling the deco can be overrulled by any other member of the team. I call 4 minutes and maybe Gareth disagrees because he thought the depth was a little more than I did. He calls 5. We do 5. Up we go to the next stop. The most conservative person wins.

Although we start the ascent with roles, they can change at any time. For example, the person who puts the bag up at 21M will almost certainly not end up with it on the surface becuase they will hand it off at some point to do something. Why bother handing it back when they have finished, there's no need. Similarly with the time. We are all looking at the time anyway, so we are checking each other's work. 1 person calls the deco, bu tthey can be overruled if someone wants to pad it out.

[Mal Bridgeman]

Originally Posted by Garf

When we move to the 18m stop then we say how long we are staying there for. If we are rounding up the deco to the nearest 10 mins then thats the only signal you need. you now know how long each stop is going to be in the intermediate stops and how long the stop will be at 6M

Remember that we have 5 equal stops, and then the same again at 6 metres. so that means we can multiply whatever signal we are given at 18 metres by 10 and we know how much deco we have. 4 minute stop called, 40 mins deco to do. We know we are gonna have to do 4 at 15, 4 at 12, 4 at 9 and 20 at 6. Simple.

If we are not doing the rounding up thing becuase, well for whatever reason, then at each stop the person calling the deco can be overrulled by any other member of the team. I call 4 minutes and maybe Gareth disagrees because he thought the depth was a little more than I did. He calls 5. We do 5. Up we go to the next stop. The most conservative person wins.

Although we start the ascent with roles, they can change at any time. For example, the person who puts the bag up at 21M will almost certainly not end up with it on the surface becuase they will hand it off at some point to do something. Why bother handing it back when they have finished, there's no need. Similarly with the time. We are all looking at the time anyway, so we are checking each other's work. 1 person calls the deco, bu tthey can be overruled if someone wants to pad it out.

Garf

I don't get this....don't you indicate the time you propose to stay at 21M after everyone has switched? why is the 18M time the guide?

Cheers
Mal

[Digger]

AIUI, the 21m stop is always (within reason) a 3 min stop isn't it? So calling 4 at that point ain't right, becuse the 21m stop isn't 4 minutes.

Cor, I could be a proper DIR diver and everything. I'll get on the DIRUK boat next week, it'll be great.

Digs.

[copperband]

And open the oxygen window (did you let one off Digs?)




<Sitting at the back of the class reading with interest>

[Mal Bridgeman]

Originally Posted by Digger

AIUI, the 21m stop is always (within reason) a 3 min stop isn't it? So calling 4 at that point ain't right, becuse the 21m stop isn't 4 minutes.

Cor, I could be a proper DIR diver and everything. I'll get on the DIRUK boat next week, it'll be great.

Digs.

Hopefully Garf will explain but I thought the 21M stop was a minimum of 3mins. In other words if you had 20 mins of deco to do that would give you 2s on the intermediate stops but you'd still do 3 @21M. In which case I could see that 18m is where you would get to know what's being called as the duration of the rest of the stops.

If you had 40 mins of deco to do, though, I thought you did 4mins @21M then 4s on the intermediate stops, so you'd know at the 21M stop.

Mal

[Garf]

correct. 21M is a minimum of 3 mins. so you might call 3 mins at 21, but then only 2 at 18 if its 2's all the way up, so you dont really know how much deco to do at 21 unless you make a specificate point of communicating it across the team. However, at 18 is becomes apparant anyway.