Weight Belt

[Mandy3206]

In deco bussiness, that's whole diferent story, I was under the impresion that the discusion was in NDL

Was it?

 

[cornfed]

In deco bussiness, that's whole diferent story, I was under the impresion that the discusion was in NDL

Was it?

Well... since we're in the DIR section I'd have to say that every dive is a decompression dive so it's a moot point.

 

[Mandy3206]

I was under the impresion that DIR was being used in recreational diving too.

I'm well awre that DIR originated in WKPP and it address a very Tech methodology.

To my knowledge, the vast majority of diving is made by NDL, I only know 3 people that do Decompression dives and I'm very far from Deco dives.

Is DIR only aimed at the Tech comunity?

 

[cornfed]

I was under the impresion that DIR was being used in recreational diving too.

<snip>

Is DIR only aimed at the Tech comunity?

This is getting a little bit off topic but the DIR view of recreational diving is a bit different then what is oftern presented in the PADI, NAUI, etc OW classes.

The idea is that every dive is a decompression dive. That doesn't mean that you have to take a stage bottle with oxygen or some other deco gas. It means that you always make a slow, controlled ascent and "safety stop". The idea of staying within the NDLs so you can make an emergency swimming ascent doesn't really fit into the DIR mindset. Instead you and your buddy plan enough reserve (aka "Rock Bottom") so that you can still make a slow ascent and "safety stop" should one of you run out of gas. It doesn't matter if the dive is only 30 minutes at 60', you still want to be able to make a slow ascent and "safety stop".

DIR is very much applicable to recreational NDL diving. There are just a few sublties in how it is approached. Does this make sense?

FWIW, I keep saying "safety stop" because GUE advocates making a one minute stop at each of 30', 20', and 10' instead of the 3 minutes at 15' which is more often taught.

 

[JimC]

I have to say it.. take the class.

No, seriously..

A 30 minute dive to 80 fsw on 32% is a deco dive.

 

[lamont]

With my BP and STA, I just need to wear 4# in my integrated system, if by any reason I loose this weight (may only loose 2#), I won't skyrocket to the surface, just will be a minor inconvenience and probably won't have to abort my dive

I tried configuring myself with a steel STA, steel tanks and weighted BP to get nearly all my weight up high and I did headstands for that dive. I found that I need to have 10# down around my waist in order to have decent trim.

 

[Mandy3206]

I used only 12# before the BP, and found that with the new setup, I only needed an aditional 4# to be like before.

I'm switching to 6# next week just to check the diference at the end of the dive.

 

[mer]

No, you're correct, that's why the ditchable weight should be a smaller amount of weight, lets say 2-4 lbs.

Then again at 10' there shouldn't be a problem if you float to the surface suddenly.

Yes and No. Assuming you are properly weighted (able to hold 10' stop and control your ascent to the surface with nearly empty tanks), losing 2# of gas shouldn't affect you too much. However this is only true of you still have a decent amount of gas left in your tanks.

I'm in a world of hurt if I lose 2# with 500 psi at my 10' stop.

Of course here we have a solution to a problem that doesn't exist; our weight shouldn't be loseable.

Even "floating" from 10' to the surface quickly is a bad idea. You're going from 1.3 ATA to 1.0 ATA. That's about the same pressure change as going from 60 feet to 33 feet. Our safe ascent/minimum deco profile dictates that we take at least 30 seconds to go from 10' to the surface, and since that's the fastest pressure change we incur during the dive slower is better. I would also argue this is more important for a "recreational" dive close to the NDLs than for a properly executed "deco" dive because we are coming out of a rec dive much less "clean" than a deco dive with high O2 content decompression.

 

[Whirling Girl]

I'm in a world of hurt if I lose 2# with 500 psi at my 10' stop.

Of course here we have a solution to a problem that doesn't exist; our weight shouldn't be loseable.

Exactly. The ditchable weight issue is a pet peeve of mine.

Mandy3206, why carry all the paraphanalia for ditching tiny amounts of weight in the extremely unlikely event that you want to surface just a little faster? If 2lbs is all you think you would need to ditch, why ditch anything at all? If you really want some momentum upward, add a little gas to your BC or your drysuit; at least you can dump it.

In DIR diving, problems are solved underwater if at all possible, so that you can ascend normally and do all your deco stops (NDL of course) and surface normally. That's why you have buddy teams, rock bottom and other gas management rules, safety drills, blah blah blah.

So consider the question, what are the circumstances in which you would ever need to ditch weight at depth? Whatever that scenario is, there's probably a better answer.

 

[fgriffith]

I'm not advocating ditching your weights, just providing a means to don your own gear with the weight belt on outside if this is what you prefer. This a very common question from new users of BP/W's


I do have question however. I'm not baiting anybody. I do want to know.

What is the DIR position regarding weight belts, and or ditchable weight in general?



Thanks,



Tobin

According to George Irvine, the weight belt should be over the crotch strap when you're diving with a wetsuit and under the crotch strap when you're diving dry.