Minimum Diving Weight

[MauiScubaSteve]

Just because you are surrounded by lazy/incompetent instructors does not mean ALL instructors are lazy/incompetent. The reason SOME Instructors overweight...SOME Instructors overweight their students religiously...

The reason instructors overweight their students is so they don't have to mess with them not being able to get down to perform skills. The problem is they never undo that training so the diver keeps diving overweighted thinking that's the way it should be done in the real world.

...

I prefer to dive with as little weight as I can get away with for several reasons:

1) It's less weight I have to hike around on land.
2) It's less weight I need to drag around underwater pulling my waist down.
3) It's easier for me to surface swim around as light as possible to crawl over kelp and navigate the surface.
4) it's safer. If there was ever a problem with an inflator hose coming off or something leaking, even with no air in my wing I know I will be able to float.

Beginning divers are often tense and anxious (causing greater net lung buoyancy), they often will not get horizontal or slightly head down when swimming underwater and they often bend their knee waayy too much because someone said "kick" instead of "fin" your fin (both causing more upward propulsion), when vertical at the surface trying to descend they are also trying to stay oriented to their buddy or instructor and they squirm/"kick" themselves up inadvertently.

Some new divers will take nearly a hundred dives to calm down enough to get the right weight; some will probably never get it.

Some new divers are comfortable enough in water to hear the "proper" techniques being spoken by others and they are easy to get to proper weight in 4 dives

Yes instructors do overweight their student religiously. It happened to me when I got certified, and I saw it done all the time as I was later DM'ing.
The standard protocol was (and still is) if a student can not sink when they dump their air they are then loaded up with clip on weights out of a float tube or similar recepticle until they can. This means going down feet first.

Come to Maui and watch the Instructors in the water; I see more underweighting than overweighting; kind of a knee-jerk reaction to years of stupid statements like "Instructors always overweight."

I and nearly every Instructor I have worked with are diving with up to 8 lbs extra on training and guided dives, because we have weighted our charges very close to minimum for a perfect world, and then we may have to add weight during the dive to keep them down. If things work right, we then demonstrate proper diving, while being grossly overweighted. It is not hard to dive well with a bunch of weight; try watch Thunderball again!

4 lbs heavy compared to the books perfect is less overweighted at 30 fsw than book perfect at 100 fsw. Whining about overweighting is a red herring IMHO, because if you dive like I show you how to dive, 4-6 lbs heavier than book perfect is no big deal to dive well.

 

[Akimbo]

Yes instructors do overweight their student religiously. It happened to me when I got certified, and I saw it done all the time as I was later DM'ing.
The standard protocol was (and still is) if a student can not sink when they dump their air they are then loaded up with clip on weights out of a float tube or similar recepticle until they can. This means going down feet first.
I guess this is the new way to dive, but I don't buy into it. I think it's wrong and unsafe...

What a shame. My most cherished experiences are those dives with great visibility and gently flying/drifting through kelp forests at an acute down angle. The techniques you described makes it really awkward coupled with the eco-centric notion that actually touching anything on the sea floor is a crime against humanity.

Working divers are often intentionally heavily over-weighted — on the order of 30-60 Lbs. Being that heavy is a little disconcerting even with a down-line and skilled tenders.

If Guillaume Nery's base jump video does not make a person yearn for neutral buoyancy then they will never be at one with the sea… IMHO

YouTube - Guillaume Nery base jumping at Dean's Blue Hole, filmed on breath hold by Julie Gautier

 

[Akimbo]

… Come to Maui and watch the Instructors in the water; I see more underweighting than overweighting; kind of a knee-jerk reaction to years of stupid statements like "Instructors always overweight."
...

halemanō, do you think overweighting is less of a problem in the warmer waters of Hawaii? Both ZKY and I live where the choice is between a 7mm full wetsuit or a drysuit.

Would a simple and fast method of finding neutral buoyancy change anything for the better? Are some (not all) dive instructors over-weighting students because it is too time consuming to explain and help them reach neutral buoyancy?

I just came back from a swim/freedive at a small beach down the road — Abalone season opens back up tomorrow! I took the time to watch Scuba divers slowly plowing through the water generating a bow wave like a barge. All of them had fully inflated jacket BCs and swam on their backs. I saw the same thing in San Diego when I lived down there. I could only see two groups reach their dive site and descent. I didn't see any fins break the water… is this the "new norm"?

 

[MauiScubaSteve]

There are a number of Instructors here on SB from the Puget Sound area, and I get the feeling from their posts that they are not overweighting their students.

People do not generally conform to one category, so even a simple fast method would only be viable for a small group IMHO. Some people are easy to get right quickly, others take a while, a few take a long time and there are likely some who will never get it right!

Yesterday I guided my most regular father/daughter customers on a shore dive of the St. Anthony wreck. This is a charter boat dive for ~98% of the divers who do it, scooter dive for ~1.5%, kayak dive for ~0.4%, and then there are the ~0.1%-ers!

We slowly plowed barge like for over 20 minutes until we could see the artificial reef tire modules 60 feet below us, just like we did the last time we did that dive and just like I've done on almost all long surface swim shore dives. Why would our fins ever break the water?

When we did our free descent, we oriented to head lower than body/fins in the first 10 feet. Why would our fins ever break the water?

The only long surface swim shore dives I would snorkel are ones where I have to negotiate a serpentine path to avoid reef and/or rocks, or shallow reefs that are part of the beauty of the experience.

 

[Eric Sedletzky]

The empiric way I use to fine tune my weights is to use a couple of 1lb weights. Subtract 1lb of wt and do a regular dive and check buoyancy at the end. If still negatively buoyant at the end, on the next dive remove another 1lb of wt. By using a 1 lb weight change, the error is forgiving enough that it won't ruin your dive.

Using 1lb weights is also useful for adjusting trim.

Adam

That's a very good method.

 

[aquaregia]

Head-up descents sure strikes me as an uncomfortable way to dive.

I was taught heads-up descent. Facing your buddy, floating at the surface in a jacket BC, signal to go down and vent the BC. You're pretty much vertical then. Now drop rapidly until you hit the bottom in a cloud of silt with your ears screaming at you.

I think I was converting from vertical to horizontal within a few feet of the surface by the end of my checkout dives, or perhaps a few dives later. By dive 10 or 15 I was starting horizontal as I found it was easier to keep close to my buddy if I was in a swimming position. It did take a bit of work though because I had to pay attention to my descent rate as I couldn't just fin to counter it when my ears are problematic.

So to answer your question, yes newbies do it, and yes we are taught it. It never felt natural though.

Sorry for the off topic.

 

[Eric Sedletzky]

I was taught heads-up descent. Facing your buddy, floating at the surface in a jacket BC, signal to go down and vent the BC. You're pretty much vertical then. Now drop rapidly until you hit the bottom in a cloud of silt with your ears screaming at you.

I think I was converting from vertical to horizontal within a few feet of the surface by the end of my checkout dives, or perhaps a few dives later. By dive 10 or 15 I was starting horizontal as I found it was easier to keep close to my buddy if I was in a swimming position. It did take a bit of work though because I had to pay attention to my descent rate as I couldn't just fin to counter it when my ears are problematic.

So to answer your question, yes newbies do it, and yes we are taught it. It never felt natural though.

Sorry for the off topic.

Not off topic at all, this is a great discussion.

Think about this.
With this new style of training (dump your air and sink like a rock), what if your LP inflator was to come off because of a broken zip tie that was overlooked, or say the plastic elbow where it goes into the bladder was to break when you are on the surface and all the air would escape out of the BC, what would happen?
Do you think a brand new diver would be able to find a reg to start breathing off and know how to grab weight integrated tabs to dump weight to get back to the surface before being pulled down on a runaway decent? What if his mask was not in place on top of trying to find a reg and find releases to dump weights, do you think this would add to stress that could lead to full blown panic?

What if the diver was weighted correctly so the BC could be emptied completely on the surface and the diver could still float. This is a much better and safer way to go about diving and to perform surface swims don't you think?

 

[aquaregia]

For sure. With my usual weighting I have to completely empty my lungs for as long as I can, then take a tiny breath and breathe all the way out again, which gets me slightly below the surface where I'm negative. That's with a dry(ish) wetsuit; for dive #2+ I usually sink pretty easily from the surface. I might be a little heavy as I can maintain 5-10' with 500-1000psi in my tank, but I prefer playing with crabs and sanddabs to a surface swim back in.

I assume you swim down, having no BC. Would you recommend swimming down even with a BC?

 

[Akimbo]

…With this new style of training (dump your air and sink like a rock), …

This sounds exactly like Jacques Cousteau in the Silent World describing the old way of diving.



I believe a description of effortlessly soaring down into the blue with the new Aqualung followed.

 

[yarik83]

When I started diving I was told that all I needed was 12lbs. I found out the hard way that I really needed to dive with 14. Then after having my weight dialed in I bought a video camera and my weight went out of whack so I had to increase my weight by 2lbs. I ended up diving with 16lbs until I went to the keys and water being different than in west palm beach I could not sink so I went to 18lbs. Then I went all around caribbean several times and found out that 18 was too much so I went with 17 then back in florida I was back to 16 until I purchased other gadgets and my buoyancy went out of whack again. Overall after being really really annoyed time after time I decided that its best to overweigh myself with 18lbs. Ever since then I never had problems with my safety intervals nor with buoyancy control at any depth.

I have seen dive masters cheat especially in places like cozumel. Grab a plastic bag and fill it up with sand at the bottom. After safety stop they just dump it back. I thought about doing something like that for a while until I started running into all these stingrays everywhere I dive so as a safety precaution I ruled that out completely. Then I figured out what the actual problem was. Here in Florida's drift dive heaven main problem is that current is all over the place. It goes one way on the bottom and another way at the top so while rest of your party is swimming one way at the bottom you are panting your way trying to keep up with the flag mid way at 15 feet during your safety stop. Come to think of it the only time I had an enjoyable safety stop at west palm is when my entire group surfaced at the same time so we all drifted together and it was a lot easier to maintain buoyancy.

So after 150 some dives I made a pact with myself. I overweight myself during drift dives so that I can swim against the current and not go up and down up and down while frantically swimming there for 3 minutes and use less weight during other dive conditions.