Over vs underweighted

[dumpsterDiver]

Then we will have to agree to disagree. My viewpoint comes from working with brand new divers for a good number of semesters now.

It's better for someone to be underweighted, especially during open water checkouts (hence the word "student" ) than it is for them to be overweighted, as a general rule. I would much rather have to get out of the water to get some more weight, than to pick up a dead student off the bottom. Obviously there are exceptions to this rule and I listed a few.

Same with most divers -- I'd rather they be at the surface, complaining about missing out on a dive from being underweighted, .

I seriously wonder how somone can claim to be expereinced and have this kind of opinion. You are simply wrong! A diver that is underweighted, will NEVER feel comfortable and in control during the dive. This is stessful and in itself presents a safety hazard, particularly to a new diver.

An expereinced diver will ALWAYS opt to over-weight themselves rather than take a chance at underweighting, if they are a little unsure about weighting with a new rig. Managing the situation where you are 5 or 10 lbs over weighted is relatively easy, but being 8 lbs underweighted is intolerable.

 

[bfw]

If I HAD to be either one, I would choose overweighted.

Why would you ever HAVE to be either one?

Of course, if you work on reducing the weight you wear, when you get to the point where you use none, it's pretty hard to be underweighted.

 

[String]

A diver that is underweighted, will NEVER feel comfortable and in control during the dive. This is stessful and in itself presents a safety hazard, particularly to a new diver.

Depends when on the dive. If they're 3-5lbs they may well be OK initially until they've breathed some gas down. Some underweighted divers will only realise right at the end with a near empty tank. It all depends HOW underweighted.

With new divers i generally see underweighted (minor) usually end up in a slow ascent just not able to stop. Overweighted ive seen many of them do missile impressions as they struggle to cope with the massive amount of rapidly expanding gas in their jacket and drysuit. Overweight is the most dramatic of the 2 from my experience.

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EDIT:- With the above scenario the diver and/or his buddys then convince each other that the inability to hold a stop meant they need MORE weight..So they shove even more on and make the situation even worse. Ive had people tell me they NEED 15-16lbs extra of weight and "KNOW" they do for this reason
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As experience progresses though it becomes less of an issue as you're used to it. A diver starting a dive with a twinset and stage is due to the laws of physics going to be starting that dive about 9kg (~20lbs) overweight purely due to the weight of gas he's carrying in his tanks. A new diver that massively overweighted id venture would have no buoyancy control what so ever, kick the silt up and suck a tank dry in 15 mins.

 

[String]

Why would you ever HAVE to be either one?

I overweight by 1-2kg in winter. The extra few litres of gas in my suit helps loft my undersuits a bit more and keep me a bit warmer.

 

[SparticleBrane]

With new divers i generally see underweighted (minor) usually end up in a slow ascent just not able to stop. Overweighted ive seen many of them do missile impressions as they struggle to cope with the massive amount of rapidly expanding gas in their jacket and drysuit. Overweight is the most dramatic of the 2 from my experience.

Ding ding ding...winner!

But being light means you CAN'T control your ascent at the end of the dive, and with any significant nitrogen accumulation, this is begging for an injury.

Is it? Remember that today's 30fpm ascent rate is fairly conservative in itself, it used to be 60fpm, with no safety stop either. For most of the dives that most students do on their open water checkouts, and what most brand new divers do -- the risk of DCS from an 'uncontrolled' ascent (slowly rising to the surface because they're 1-2lbs underweighted) is practically zero.

 

[bfw]

I overweight by 1-2kg in winter. The extra few litres of gas in my suit helps loft my undersuits a bit more and keep me a bit warmer.

But that's a CHOICE, and doesn't really represent overweighting - it's proper weighting for your thermal protection. You could probably use less weight in the summer than you normally do if you kept the suit so tight it caused friction bruises, but that doesn't mean you're overweighted diving the suit in reasonable comfort.

 

[ebenburger]

More is better than less. Had similar problems with my HUB system but additional weight solved it. With more weight you can solve the problem yourself, but with too little weight you are dependant on others to help you and this is exactly what you try to avoid.

 

[String]

But that's a CHOICE, and doesn't really represent overweighting - it's proper weighting for your thermal protection. You could probably use less weight in the summer than you normally do if you kept the suit so tight it caused friction bruises, but that doesn't mean you're overweighted diving the suit in reasonable comfort.

It still represents overweighting however you want to define it. Less air does not equal friction bruises - that would be too tight. Purely the more air shoved in the suit the warmer it is. For me thats about 2kg in the winter on top of an already comfortable suit volume. I know what weight i need and i deliberately add to it in order to stay warmer.

 

[friscuba]

Then we will have to agree to disagree. My viewpoint comes from working with brand new divers for a good number of semesters now.

It's better for someone to be underweighted, especially during open water checkouts (hence the word "student" ) than it is for them to be overweighted, as a general rule. I would much rather have to get out of the water to get some more weight, than to pick up a dead student off the bottom. Obviously there are exceptions to this rule and I listed a few.

Same with most divers -- I'd rather they be at the surface, complaining about missing out on a dive from being underweighted, or how their dive wasn't enjoyable (been there myself; never fun to have that feeling that you're slowly ascending and there's nothing you can do about it except kick down), or even possibly bent, than still down on the bottom because they couldn't get back up.


Most divers carry around way more weight than they need, many by 10-15lbs (or more). That's a lot of weight to swim up (and try to keep up while bobbing at the surface), especially if they panic and forget to drop a weight belt.


A lot of what I'm saying comes from wanting the opposite of most instructors and DM's -- they'll overweight people (again, sometimes by ridiculous amounts) to plant them on the bottom and perform skills and "make sure they stay down". Personally I feel this is exactly the opposite of what one would really want...I'd rather they have trouble going down than coming back up.



I suppose I should also mention that I strongly feel this way for students and for brand new divers. As one progresses through diving and learns to manage their buoyancy much better I don't honestly have an issue with being a tad overweighted (as long as it isn't ridiculous).

Wow. I gotta agree with the other poster. Mildly overweighted will eliminate a lot of problems. The 10-15 pounds heavy you mentioned means someone really weighted them wrong, way wrong, but 3-4 pounds heavy beats the heck out of one pound light on a check out dive.

I can't think of any time I haven't been able to "fix" a diver that was a few (I'm not talking 10-15 .. whoever's that much overweighted has been getting some poor advice) pounds overweight in a matter of seconds by using their inflator. Underweight is something I hate seeing because it's a dive blower as far as comfort goes, and potentially dangerous if students end up on or near the surface when they shouldn't be.

 

[Twistedarts]

Ive seen far more polaris style rapid ascents from overweighting than i have from underweighting.

that may be, however I was taught to "swim" my rig. I do not use my wing to get to the surface and usually I swim down the line as well. ( i was taught in the 70's with a plate and horse collar)