Diving Safely Without A BC

[Rich Keller]

Some divers nonetheless dive without a BC, at least some of the time, either because they are vintage equipment enthusiasts or for reasons of simplicity and streamlining.

Under what circumstances, if any, do you believe it is safe without a BC? What skills or knowledge do divers need before undertaking this style of diving?

This is easier to do in shallow water where variables of suit compression is less of an issue. This also allows for use of a smaller tank again reducing the difference of the variables between a full and empty tank. Getting your weight exactly right is of course critical. I find my weight by getting neutral at the surface with a full tank and all my other gear on. Once I know that i split the difference in weight between a full and empty tank. This makes me slightly negative at the beginning of a dive when I want to be on the bottom and slightly positive at the end when I want to be on the surface. In the case of a 30' dive using a 30 cu/ft tank I am only dealing with an extra pound +/- that is very easy to compensate for by swimming, breath control or both. Most important is to have your weights on a belt so they can be dumped quickly in an emergency.

 

[BilgeFish]

Im sort of new to scuba diving but have done plenty of hookah diving (mostly for lobsters and abalone etc..) obviously hookah is with no bcd, weighting according to suit and depth. We have at times when the surface is either to weedy or rough not been able to get our boat close enough to the shore/rocks for our hookah lines to reach so have weighted some steel tanks and strapped together and sunk to the bottom running hookah lines off of these. It does create a little problem where the hookah line starts down goes up and back to you but is manageable. Usually two of us use four 100 steels and switch over underwater. Where only at a max 12m and mostly between 5-9m i wouldnt do this any deeper yet without more experience doing it. Probably wont need to do it all now i have scuba gear (we will see im still finding the extra bulk of gear harder to get in under some rocks where the crayfish are...need more dives with the scuba)

From this experience i would never strap a tank to me and try to scuba dive without a bcd. The bouyancy of the tanks changes it took us a while to find the correct weight where they were a manageable weight without being to lIight to move in the current on the bottom when getting empty. Im sure it could be done but i think the hassle of finding the right wieght for the depth and compensating for the changing tank bouyancy etc.. isnt worth it. If you dont want to dive with a bcd and dont have a compressor buy a hookah line and regulator with a din or yoke.

 

[REVAN]

Im sure it could be done but i think the hassle of finding the right wieght for the depth and compensating for the changing tank bouyancy etc.. isnt worth it.

It's just the same math that every diver should already be doing for each dive. It really isn't a hassle, unless you are someone who thinks proper dive planning is a hassle.

 

[george_austin]

@BilgeFish - what do you mean "isn't worth it" ? a "hassle" - As Revan said above - it's just what MUST be done by every diver all of the time. This goes to the core of the problem many of us see with the misuse of equipment and the almost universal acceptance of equipment dependency versus diver dependency. Proper weighting is a CORE skill - without it a diver is an accident waiting to happen - or a fatality in worst case

 

[Rich Keller]

Im sure it could be done but i think the hassle of finding the right wieght for the depth and compensating for the changing tank bouyancy etc.. isnt worth it.

This is basic diving information that every diver should know! Unfortunately most instructors do not stress this enough preferring to sell you equipment to solve the problem instead. Back when I started BCDs had not been invented yet so more time was spent on this in class.

 

[John C. Ratliff]

...Exposure protection: this is the important one. You can't use thick wetsuits and dive deep. This is the secondary function of a BCD, and as long as you are diving in a thin ish wetsuit 3mm or shorty, or no exposure protection, it is not that bad to work with.

As one who had a small role in the development of the BCD, let me say that the primary reason for the BCD is buoyancy compensation. That's where we got the acronym, BCD, or Buoyancy Control Device. They were initially developed for use with thick wet suits, where loss of buoyancy at depth was the problem. BCDs were the solution. In the 1970s, BCDs were not used with the high end dry suits of the time, such as the Uni-Suit. They had their own means of buoyancy control.

Because the BCDs now exist, heavy, high pressure tanks are now available that would be un-divable without a BCD. But that always carries the risk in warm water of a failure of the BCD, which is more why they are now "required" than anything else. These tanks weigh so much that BCDs must be use to be neutral in the water, but they also add drag. It is interesting how this has evolved to a point where the BCD is now more expensive than the regulator.

The secondary function of the BCD is safety, but some fail miserably at this, as they won't float an unconscious diver face-up.

'Just some perspectives from the past.

SeaRat

 

[JamesBon92007]

Current teaching from PADI is that it is unsafe to dive without a BC. I assume other agencies teachings are similar.

Some divers nonetheless dive without a BC, at least some of the time, either because they are vintage equipment enthusiasts or for reasons of simplicity and streamlining.

Under what circumstances, if any, do you believe it is safe without a BC? What skills or knowledge do divers need before undertaking this style of diving?

I didn't read the entire thread so forgive me if I'm repeating what others have already said, but as far as "safe" goes I'm thinking that at somewhere around 60-70 feet some kind of variable flotation device (May West, snorkel vest, etc) is recommended. The issue may or may not be safety but I don't think it would be a very good idea to dive, say, inside a shipwreck without neutral buoyancy control. Other conditions could include caves and delicate coral reefs. But, as others have said, anything down to around 40 feet can be easily accomplished with proper weighting. The thinner the wetsuit the easier it is, but I've done thousands of dives with a 1/4" farmer john at those depths without any form of BC. I also highly favor using a steel 72 tank over an aluminum 80 because there is less difference in the buoyancy between a full tank and an empty tank. I did not aspire to become a vintage diver--I became one by default Another reason not to wear a BC for beach diving is that it can add a lot of mass and bulkiness which I prefer to do without while entering and exiting through the surf (streamlining).

The powers-that-be in Hawai'i must have read that PADI passage as it is illegal to dive on Maui without a BC (and a diver's flag). I'm not sure about the other islands.

 

[REVAN]

The powers-that-be in Hawai'i must have read that PADI passage as it is illegal to dive on Maui without a BC (and a diver's flag). I'm not sure about the other islands.

That's interesting. So, now we need a legal definition for what constitutes a BC. The law would be pointless without that. Anyone know what that is?

I say that I dive without a BC, but that's really just terminology. I have both buoyancy compensation and buoyancy control when I'm diving. First order compensation is with selecting the right amount of weight to be able to effectively control my buoyancy with my breathing (second order compensation). There is nothing uncontrolled or uncompensated about it. Do I need to start saying that I use a BC even though I'm just using a backplate and harness so that I can be "legal"?

PS - The freedivers on Maui must be in a pickle.

 

[JamesBon92007]

PS - The freedivers on Maui must be in a pickle.

Yes, they must. Seriously though, there might be a requirement for a flotation device for snorkeling but I didn't see anyone using one.

I considered just taking my old inflatable vest (Mae West) but then I'd need to take along a backpack. I do not like to do "checked bags" and simply cannot get one into my carry-on without leaving other gear behind. I don't know if the Mae West would meet the requirements or not but if nabbed I'm sure I could put up a good argument. I asked when I was on Maui at the dive shop and they did not rent backpacks. It might be possible to find one cheap on Craig's List while there.

 

[John C. Ratliff]

Oh, I should mention that you should be okay with the skill of ditching some weight in emergencies (really a skill all divers should be good with).

Also, if the water is rough and/or I feel there is any chance I may have to spend some extended time on the surface (and especially if I have very little weight to ditch in the first place), I like to have my snorkel with me. A normal snorkel, I'd carry in a pocket to keep it out of the way during the dive. Presently, I like to use one of these inexpensive DIY loop snorkels because it doesn't get in the way or flop around while I'm scuba diving and I can have it in place ready to go at any time.

Note - You may need to rewind this to start at the beginning. It's starting at 4:30 for me, but I can't find a reason for it.

Ron,

You should blog this post so others can see how you make this snorkel. Ever since I saw this snorkel on your videos I have wondered about it. Thanks for posting this DIY snorkel.

SeaRat