Why would you want to dump weight?

[MikeFerrara]

If you're correctly weighted there shouldn't really be any reason to drop your weights at depth. Doind so is going mean a uncontrolled ascent.

I have NEVER seen any one need to drop weights at depth but I have seen MANY divers lose weights from quick release systems especially the ones held in my velcro. I also fine them on the bottom often with no diver attached.

At the surface you of course shouldn't hesitate to drop weights if you need to in order to stay at the surface.

One problem is many of the integrated weight systems seem to made for tropical diving. They work ok if there isn't much weight in them. Around here though divers are diving heavy wet suits and dry suits and they load the weight pouches up pretty good.

I want my weight securely attached so I'm certain not to drop them unless I mean to.

 

[garyfotodiver]

There are emergency situations that you would have to dumb weights and as a result ascend in uncontrolled way. You end up with DCS but with a chance to survive rather than die underwater.
And for this you have to be able to release weights rapidly.
Mania

Why do you end up with DCS if you "dumb" (sic) weights? Isn't recreational diving designed to keep one out of deco situations?

If you are a recreational diver, the uncontrolled ascent is the last thing to do in an emergency. Nevertheless, you should reach the surface and not suffer any effects.

How many divers out there have experienced an OOS and lived?

 

[Scuba_Vixen]

Why do you end up with DCS if you "dumb" (sic) weights? Isn't recreational diving designed to keep one out of deco situations?

If you are a recreational diver, the uncontrolled ascent is the last thing to do in an emergency. Nevertheless, you should reach the surface and not suffer any effects.

How many divers out there have experienced an OOS and lived?

Getting bent to h*ll and non deco diving are not mutually exclusive. You should have learned that in OW. You get bent when the gradient between the inspired gas pressures and the gas in tissue pressure is too great and it comes out too fast. All it takes is enough on gassing and too rapid an ascent for it to properly off gas. Divers have been bent on 40 or 50' dives.

 

[Kim]

At the surface you of course shouldn't hesitate to drop weights if you need to in order to stay at the surface.

I believe that nails it to a tee. Underwater you need your weights for control - agreed.
At the surface - after an emergency situation that caused the ascent - in rough water - no boat close - you really need to lose the weights. This could also be an unconscious diver that you brought up - he/she can't dump their own weights, and as a rescuer you need them as bouyant as possible.

 

[miketsp]

Why do you end up with DCS if you "dumb" (sic) weights? Isn't recreational diving designed to keep one out of deco situations?

You can be in a no deco situation according to your table but that same table assumes that you will be ascending at less than a pre-determined rate to allow "safe" bubbling of the dissolved gas.

 

[BCS]

I was just reading a thread in the DIR section and people were mentioning that in anykind of overhead environment (either hard or soft) that dumping weight (to the point you can't help being positively bouyant) isn't something you'd want to do. I was wondering why dumping weights in a rec situation would be anymore sensible?

Hi Mortlock,
One instance comes to mind when it may be advantageous to have at least some form of ditchable weight. If a diver uses a thick wetsuit, such as a 7mil, two piece (farmer john and jacket top), she may require a good amount of weight just to overcome the positive buoyancy of the neoprene at the surface. We checked the buoyancy on one set of medium sized 7mils in a pool and it required 16lbs in and of itself just to submerge it past the 3' mark. Conceding that a 7mil wetsuit will lose much of it's buoyancy as it is brought to depth, when the diver reaches this depth at the beginning of the dive with a full cylinder, the weight that was required to sink the suit is no longer needed since the suit has now lost much of it's inherent buoyancy due to compression at depth, the diver will then find herself overweighted and be required inflate the wing significantly to remain neutral (which also adds very noticeable drag to the diver). The diver may also be unable to swim the rig up in the event of a wing failure. In this case it would be advantageous to have at least a few pounds in the form of ditchable weight that they can lose in order to swim the rig up. Keep in mind that if the diver chooses to carry too much weight as ditchable, she may run into trouble holding the safety stop and/or controlling the ascent speed.
This is the same w/a thick neoprene drysuit as well, should both the wing and drysuit fail simultaneously (as it did for one of our students last weekend).
So at depth, the suit loses a good portion of it's inherent buoyancy as well as it's heat keeping capacity due to compression of the neoprene. For these reasons a thick neoprene suit (dry or wet) is less than optimal.

take care!---brandon

 

[MikeFerrara]

Why do you end up with DCS if you "dumb" (sic) weights? Isn't recreational diving designed to keep one out of deco situations?

If you are a recreational diver, the uncontrolled ascent is the last thing to do in an emergency. Nevertheless, you should reach the surface and not suffer any effects.

How many divers out there have experienced an OOS and lived?

Decompression sickness isn't the only concern.

A rapid ascent may very well cause you to spit out your lungs and then nothing will save you. While ascending just swallowing may be enough of a breath hold to do it. Maybe no breath hold is needed at all. All it takes is for the air not be able to get out as fast as it want to like popping a paper bag that's open a little or a gun barel blowing up because of a few drops of oil or water in it.

 

[mania]

Obviously such a simple process will also be rapid and thus the word rapid is used instead of "easy to locate and operate in an emergency situation".

You are right. That's what I meant - easy to release.

Why do you end up with DCS if you "dumb" (sic) weights? Isn't recreational diving designed to keep one out of deco situations?

You mean if you are doing a no deco dives there is no way to get DCS? That's an interesting theory. As Scuba Vixen wrote they teach about DCS during OW classes. An uncontrolled and too fast ascend is the best way to get DCS.

A rapid ascent may very well cause you to spit out your lungs and then nothing will save you.

You are right. But in case of the guy I know and wrote about - he thanks God was breathing all the way up.
When I was doing my OW I was taught how to release weights. to be honest I had the same question - why would I want to dump weights underwater. So being curious I started asking this question to a lot of experience divers. And one of them told me his story.
Mania

 

[DA Aquamaster]

It is often much easier and faster for a diver to establish positive bouyancy on the surface with ditchable weight. It can be critical in an emergancy to be able to dump a panicked divers weights on the surface.

Arguably if you are on the bottom and have to dump weight, you have already made some fairly serious mistakes either in configuration or dive planning. But as previously pointed out, you are better off being at the surface bent than at the bottom drowned, particularly if no one is going to be looking for you on the bottom anytime soon.

In the past the general idea was to make all your weight ditchable while today the trend is to have only part of your weight ditchable and/or to be able to dump 1/2 at a time to get you positively bouyant if ever needed while minimizing the rapid ascent that would ensue if all your weight were dumped.

If you ever lose your weights, you need to remember that if you assume a horizontal position with your arms and legs spread eagled you will create a huge amount of frontal area during the ascent and the resulting drag will minimize the ascent rate. Most people seem to get in this situation and ascend vertically in a fairly streamlined position with an extremely rapid ascent rate as a result.

 

[garyfotodiver]

Decompression sickness isn't the only concern.

A rapid ascent may very well cause you to spit out your lungs and then nothing will save you. While ascending just swallowing may be enough of a breath hold to do it. Maybe no breath hold is needed at all. All it takes is for the air not be able to get out as fast as it want to like popping a paper bag that's open a little or a gun barel blowing up because of a few drops of oil or water in it.

No, but Mania's post stated that if you dump your weights, you will get DCS. A simple categorical imperative.

If someone does not know to release expanding air from one's lungs during ascent, there is a good probability of some other illness or difficulty. That wasn't the question here.

What I learned in my initial training was to keep oneself out of trouble. The old maxim was that one cannot get bent on one 72ft3 tank. This is, of course, not always true.

My main concern is this. If someone is worried that he (or she) will have to dump weights during a dive, perhaps the training involved was not sufficient. More importantly, perhaps the diver's understanding of the training was not sufficient.