average depth tables???

[liamm]

As the tables suggest i was wondering if anyone provides no stop or decompression tables that are based on your average depth???

[nigelH]

Originally Posted by liamm

As the tables suggest i was wondering if anyone provides no stop or decompression tables that are based on your average depth???

I don't think they could.

Consider 12 mins at 6 meters then 25 mins at 40 meters gives the same average depth as 25 mins at 40 meters then 12 mins at 6 meters.

[MixedUp]

As Nigel says it is impossible.

If I do a 25 metre dive for an hour then my average depth is not far off the 25 metres. Run time not a hell of a lot more than the one hour. (on my RB)

However most of the diving that I do is 70 metre diving and at that depth I usually do approx 28-30 minutes bottom time which gives me a run time of 2:15 and the average depth usually is.....about 25 metres

Steve.

[Mal Bridgeman]

These links would be worth a consideration I suspect....

DIR-diver.com - Average depth for deco?

DIR-diver.com - Using the min deco table

HTH
Mal

[Mark Chase]

Whilst i am a keen supporter of most things GUE/DIR i feel average depth deco (commonly associated with GUE profiles) is just a way for shaving deco and making diving more aggressive.

I was taught to start bottom time from the moment I left the surface and to calculate deco on max depth unless it was an obvious multilevel dive.

This adds conservatism and allowed greater margin of error on the ascent.

Now we have divers ignoring decent time and taking a mid depth on the max and min working phase depths. As a result they do less deco.

Whoopy do

ALL tables offer the oportunity to calculate on max depth or average depth.

The question then is, do you dislike being in the water so much that you feel the need to get out fast?


ATB

Mark

[EdHornby]

well said Mark Chase - as a much better diver than me once said "If you do the depth, do the time"

[Mal Bridgeman]

Originally Posted by Mark Chase

Whilst i am a keen supporter of most things GUE/DIR i feel average depth deco (commonly associated with GUE profiles) is just a way for shaving deco and making diving more aggressive.

I think it would also be fair to say that the DIR divers that do this deco don't view it as aggressive but adequate for thier needs. There are countless threads on here describing how GUE trained divers do their deco, which clarify the approach to descent and the shape of their ascent which they believe gives a more efficient off gassing.

We nearly went through the whole of winter without this discussion Thanks Mark
Mal

[Garf]

Originally Posted by Mark Chase

I was taught to start bottom time from the moment I left the surface and to calculate deco on max depth unless it was an obvious multilevel dive.

This adds conservatism and allowed greater margin of error on the ascent.

I thought you used computers Mark. Do they calculate deco based on the max depth then. I thought that computers monitor what you are actually doing with regards to exposure and adjust the decompression obligation accordingly.

With ratio deco, what we do is monitor what we are actually doing with regards to exposure and reduce the deco accordingly.

Granted we don't do it as efficiently as computers, but they are checking your depth and adjusting from instant to instant, whereas we are doing it every few minutes.

so you can look at both computers and ratio deco as a means of tracking what you are doing more efficiently than a table, which has to assume a constant max depth. Or you can look at them both as shaving deco, if this is your preference.

[Finless]

Originally Posted by Mark Chase

i feel average depth deco (commonly associated with GUE profiles) is just a way for shaving deco and ............

ATB
Mark

Tsk tsk Mark. Do you mean BSACers can't do 'average depth deco' unless they make a fundamental personal change?

[liamm]

cheers for the responses, didnt mean to start an argument. Is there a course that covers ratio deco or is this the realm of GUE? not that GUE bothers me but i see it as about a year away in terms of skills and cash. However i've nearly sold my computer (ebay ends tomorrow) and will be diving over easter on a depth timer and tables. I thought it would be a nightmare but with a bit of planning it looks simpler (well less crap on my wrists anyway). If i could make tables work for me on a longer term then thats 500 quid saved on a vr3. Its just thinking out loud at the moment.

the dir min deco 30 / 32 % tables seem remarkably straight forward but i huess its more complicated when you move into greater deco obligations.