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Squidgey Member
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Discussion Starter · #1 ·
If by accident you were to find yourself tangled in your DSMB after 5M has been deployed and dragged say from 30M to 5M without surfacing after a 30 minuet bottom time. Would it be best to?
Stay at 5M for as long as possable?
or, Drop down to 10M for 10 minuets then up to 5M for as long as possable?
I only ask because if i were to find my self in this situation at least i would have a good idea as what to do.
 

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Getting Grumpy, Old and Twisted
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If it's a no stop dive with just a 3 minute at 6m safety stop requirement (say 32% nitrox back gas) then I'd go for the 5m as long as possible option.
If you had missed deco stops (depending on the back gas you are using) then again sit it out at 5m for as long as possible and get yourself checked out once back on the boat and go on O2.
 

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Ok so you've been 30m for 30mimutes that's at least 10 mins of stops, fubar time.
Thoughts that would go through my head.
What's surface cover like? What's my
Current gas? If I yellow blob will I get a 7 of O2? All things that need considering.
Without any of the above I would shout twat at myself and get back down to 15m and pull 1m a minute from there to 6 spend 10 at 6 and 6 minutes to the surface. Why? Simply because as all deco there is no magic bullet. It's up to you how hard you push.

B
Ps be aware that plan may not work for me, it definitley won't work for you :) your dive computer makes calculations, your brain makes decisions, never forget that :)
 

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If by accident you were to find yourself tangled in your DSMB after 5M has been deployed and dragged say from 30M to 5M without surfacing after a 30 minuet bottom time. Would it be best to?
Stay at 5M for as long as possable?
or, Drop down to 10M for 10 minuets then up to 5M for as long as possable?
I only ask because if i were to find my self in this situation at least i would have a good idea as what to do.
Your asking a question with so many varybles that to answer is almost imposible.
If you get dragged to a shallower depth then nothing said here will help you.

Practice deployment and worry about what happens when it happens.

My tupence worth is to stay down and do extra deco but it is horses for courses....

taz

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So you are in deco by any tables presuming air, just on the limit presuming 32%

I would stay where I was for as long as my gas lasted or 15 mins whichever was longest, that is more than enough stops for the situation you stated.

I really dont see what dropping to ten would achieve
 

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If your dragged from 30m to 5m in a rapid assent then chances are you won't have had time to ditch all the expanding air in your suit and wing and you'd end up surfacing anyway. Then you've got a different choice to make.... go back down and do some stops or shout for help.
 
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Dive tart, just can't say no :-)
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Fred one other factor to consider is are you alone or can anyone else join you? I had something similar happen to me 2 or 3 years ago. I chose to get back on the boat and go onto 100% for a while. Not sure I'd make the same decsion now but the risk of fitting whilst hanging on your own is a consideration.
 

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TTFN
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I really dont see what dropping to ten would achieve
There are procedures for omitted decompression which normally involve descending deeper than the first stop then coming up slowly and increasing the length of the planned stops by a factor.

If you shoot up from 30m to 5m then there is a chance that nasty bubbles have formed even on a non mandatory deco dive, going down again will squash them down and hopefully you can offgas without them reforming by coming up slowly.

Personally in that situation I would go deeper than 10m providing I was in the right frame of mind. I think it gives you a better chance than just getting straight out of the water.
 

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Dive tart, just can't say no :-)
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I think the poster knows exactly what they would have done - reading their profile and where it was posted - someone was having fun last night maybe? :) ;)
Good spot, should have known given it was Fred who posted :D
 

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Discussion Starter · #12 ·
To all concerned it is a genuine question that i asked my self after reading a post testerday.
At the extream end of the scale I would be solo with about 70 bar left in a 12L and a 3L pony full of air.
Accidents do happen and it is one i have not seriousley conciderd before.
At the moment the general thaught is to go back down?
 

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There are procedures for omitted decompression which normally involve descending deeper than the first stop then coming up slowly and increasing the length of the planned stops by a factor.
I understand that Rob but it is all based on ifs buts and maybes as with most of these things, you would be just aswell getting to the surface and sucking some O2 I think, either method carries no guarantees, it is all best guess...
 

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beware of limitations
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If by accident you were to find yourself tangled in your DSMB after 5M has been deployed and dragged say from 30M to 5M without surfacing after a 30 minuet bottom time. Would it be best to?
I think BSAC 88's would tell you to do something like 5 minutes, get out and drink eight pints of real ale while rubbing yourself down with a ferret.
 

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I think BSAC 88's would tell you to do something like 5 minutes, get out and drink eight pints of real ale while rubbing yourself down with a ferret.


Would not waste time getting out to drink the ale. They have hydration bladders now so the ale can be taken with you..

taz

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Discussion Starter · #16 ·
Would not waste time getting out to drink the ale. They have hydration bladders now so the ale can be taken with you..

taz

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Would vodka rot the bladder?
I like the idea no spillage waste on the rib on the way back.
I suppose it is quite important as not to confuse the Hydration bladder with the Pee bladder.
 

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It's colder than a penguin's bollocks
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A simular situation happened to a buddy i dived with a few weeks ago. He borrowed a friends thermals which unknowing changed his bouyancy.
He had 28% i had 32% so i just scrapped some deco on the dive but my buddy had around 8 mins. At 5 meters he was struggling to stay neutrally bouyant and found himself at the surface with 4 mins of stops left. The skipper asked do you want to get on the boat and breath o2 or go back down and do the rest of your stop or more. As he was to bouyant he took an extra 3kg of the skipper and went back down, of course i went back down with him just to make sure he was fine..
He was fine after but needless to say any twinge he might of got after the dive he was worried that it may be the signs of a bend..
 

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Cake Monitor
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He borrowed a friends thermals which unknowing changed his bouyancy. <snip> At 5 meters he was struggling to stay neutrally bouyant and found himself at the surface with 4 mins of stops left.
I'm still learning about all this, but if it was the thermals that were preventing him from staying neutrally buoyant at 5m, how did he sink in the first place? Could it be the weight of air in his cylinders?

If so then I guess that if you cannot sink easily with full cylinders, you need more weight? I'm only asking because in the Red Sea I had a lot of trouble breaking the surface and on one dive found myself ascending (with an empty BCD) more than I'd planned so I'd like to understand more about how it works. :)
 

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I'm still learning about all this, but if it was the thermals that were preventing him from staying neutrally buoyant at 5m, how did he sink in the first place? Could it be the weight of air in his cylinders?

If so then I guess that if you cannot sink easily with full cylinders, you need more weight? I'm only asking because in the Red Sea I had a lot of trouble breaking the surface and on one dive found myself ascending (with an empty BCD) more than I'd planned so I'd like to understand more about how it works. :)
Don't forget, the air/nitrox in an average tank weighs about 3kg. There are loads of calcs on it, both on YD and the tinerweb. Nigel Hewitt has some on his site IIRC
 

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1 litre air is about 0.0012kg, so in a 12 litre tank at 232 bar there is 232x12x.0012=3.34kg of air, which won't be there when it is empty. I know PADI do the 'eye level witha full tank' thing, but I still think that a weight check with a near empty cylinder is more useful - after all it is at the end of the dive when you are nitrogen loaded that you really should be able to stay down....:)
 
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