Thoughts about really long dive

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Changing your reg to a different tank underwater could be quite risky.

Mike Neslson did it all the time. :D
 
I vaguely remember a discussion here on SB about skin problems from soaking in water for long periods. May have included something about coating exposed surfaces with something like lots of petroleum jelly?

I seem to remember someting about that too.
 
From the other thread,

There are a bunch of things you need to worry about.

Keeping breathing
Keeping warm
Keeping Hydrated
Food Intake
Food Outtake the old #1 & #2

The best way to keep warm is to not use a dry suit but use a hot water suit with surface support. As soon as you do this you can go to surface supplied air and not worry about tanks. It also opens up the possiblity to use a helmet or full face mask like a Kerby Morgan band mask. This takes care of sleeping, but adds to the drink & eat problems.

A wet suit takes care of peeing. Pooping is another problem, Time for an enema or two before you go in the water and low bulk, high calorie foods while in it. You should think about what you will eat at least 2 to 3 days before the day you go under. The GI system needs to be just about empty of solids to make 48 hours. Save the big dinner for after your dive.

You might also want to put in a "Phone Booth" type of area where you can take your reg out of your mouth or helmet off and have a drink, eat, and communicate with the surface from an air bubble.

You can eat and drink underwater, but you will also be taking in some seawater no matter what you do. This can lead to all types of GI problems that you can not take care of in a dry suit and you will also be driving up your sodium levels from the ingested salt which drive up you liquid intake, which drives up you excretion volumes, .....

What you want to do is actually more difficult then what the Mercury and Gemini Astronauts did because they at least could open their helmets and drink/eat.

All and all I would recomemnd not doing it in the ocean but in a heated pool with a very controled environment.
 
How do you intend to do the tank swaps? You mentioned a molded mouthpiece which would indicate you plan on using the same reg for the entire dive. Changing your reg to a different tank underwater could be quite risky. I would recommend having two sets of regs so that when a new tank comes down, there's a reg in place with the air on.
I plan two have two seperate set ups both with molded mouth pieces. They will be swapped out of the water. Support divers will bring down full tanks and bring up empty tanks. I'll use a pony bottle for my BC and as a back-up air source. My drysuit will be from a seperate argon pony bottle.
 
From the other thread,

There are a bunch of things you need to worry about.

Keeping breathing
Keeping warm
Keeping Hydrated
Food Intake
Food Outtake the old #1 & #2

The best way to keep warm is to not use a dry suit but use a hot water suit with surface support. As soon as you do this you can go to surface supplied air and not worry about tanks. It also opens up the possiblity to use a helmet or full face mask like a Kerby Morgan band mask. This takes care of sleeping, but adds to the drink & eat problems.

A wet suit takes care of peeing. Pooping is another problem, Time for an enema or two before you go in the water and low bulk, high calorie foods while in it. You should think about what you will eat at least 2 to 3 days before the day you go under. The GI system needs to be just about empty of solids to make 48 hours. Save the big dinner for after your dive.

You might also want to put in a "Phone Booth" type of area where you can take your reg out of your mouth or helmet off and have a drink, eat, and communicate with the surface from an air bubble.

You can eat and drink underwater, but you will also be taking in some seawater no matter what you do. This can lead to all types of GI problems that you can not take care of in a dry suit and you will also be driving up your sodium levels from the ingested salt which drive up you liquid intake, which drives up you excretion volumes, .....

What you want to do is actually more difficult then what the Mercury and Gemini Astronauts did because they at least could open their helmets and drink/eat.

All and all I would recomemnd not doing it in the ocean but in a heated pool with a very controled environment.
The problem with a hot water suit is that according the the folks at Diver's Almanac and Sourcebook, it's not a record if their is anything surface supplied connected to the diver. That's why I can't use hookah etc. This also rules out the possibility of a phone booth type deal. I am however going to use double drysuit heaters with wet swap batteries. I am going to consult with a dietition who has dive knowledge to help think through proper diets for before the dive. During the dive, I am going to drink from hydration pouches (eg camelbaks) and eat those energy gels I use when I long distance run and backpack. They should allow my mouth to have a pretty tight seal around them to minimize salt water intake.
 
The whole thing sounds pretty risky, so be careful...

Maybe talk to David Blaine for advice... I stopped by Lincoln Center several times to check him out when he spend 177 hours under water a few years ago... He used a facemask and surface supply, but there are probably some things that are similar!

Mike
 
The whole thing sounds pretty risky, so be careful...

Maybe talk to David Blaine for advice... I stopped by Lincoln Center several times to check him out when he spend 177 hours under water a few years ago... He used a facemask and surface supply, but there are probably some things that are similar!

Mike
Although in theory sometthing like this is risky. I figure that I or one of the doctors monitoring the dive via live camera stream can pull the plug at anytime if something is not right. I'm going to be just feet from a dock staffed at all times durign the dive by rescue divers and if anything does go wrong there will be an ambulance their. Although David Blaine might not be the best resource, I do plan to talk to Jerry Hall as he did something similar but much longer in fresh water.
 
I think the thermal issues will be you greatest problem. I don't know anything about dry suit heaters, but do you have enough batteries to run for 48 hours? I would be wearing very heavy rubber snow boots over the dry suit feet. Sounds like you will not need fins. If you pick the correct boots, this will help insulate your feet a bunch.

I would also consider chemical heat packs that you could apply externally to your hands and then slip your hand and heat pack into an independent neoprene pocket to warm the hands.

Also, I think you could help with the thermal battle by having warm drinks. Can warm drinks be brought from the surface? They could easily be stored in a cooler full of very warm water before being brought down to you.

Keeping your head as warm as possible will be critical to success.


Have you thought about weighting? Wearing a typical weight belt or other normal weighting systems would kill my back. I would try to work out a weighted or fixed platform, and then wear a typical BP harness (with a bunch of extra D-rings mounted on it) and then have numerous attachement points from which I could clip myself off to the bottom. Thus you would be floating slightly above the bottom. I think you might want removable ankle weights and possibly a weighted backplate and maybe even some weight belt(s).

I think if you have the option to move weight around and change your position from time to time, this will increase comfort a lot. Could someone from the hospital find a few of those xray shield blankets with lead in them? They might be perfect to drape over your legs if you can figure a way to lay on your side or back.

I would also be experimenting with swivels on my regs and also possibly the new flexible hoses to increase comfort. I also would not assume that wearing the primary tank on my back would be the optimal method. If you used a weighted platform, you could rig some longer hoses and then route them around your neck to increase comfort. If you choose to use a typical scuba second stage and mask.

All this stuff would take some experimentation to work out.

I think the FF mask is probably the best way to do this. Switching out to a normal mask and reg to drink would be the least of your worries. I would also work out the details for switching tanks, With a FF mask (or any reg, really) you can rig a quick disconnect that would allow tank replacement to be simple and easy and not require you to even remove your regulator.

I would also plan on using manifolded double tanks as a gas source, especially if they will be laying next to you rather than wearing them. The bigger supply in doubles would make the logistic easier for you and top side support.

Also, I would investigate the potential benefit of breathing pure oxygen for the last 20 mintes of the dive to help eliminate nitrogen. Or possibly even have the last tank 50% oxygen and use that for an hour or so before ascending.
 
I think the thermal issues will be you greatest problem. I don't know anything about dry suit heaters, but do you have enough batteries to run for 48 hours?
I plan to use wet connect batteries. We will have enough so that we can charge some and have some being used plus a few for backup.

I would also consider chemical heat packs that you could apply externally to your hands and then slip your hand and heat pack into an independent neoprene pocket to warm the hands.
This seems like a good idea but I don't know how effective it would be through drygloves and two layers of flease liner gloves. Any thoughts?

Also, I think you could help with the thermal battle by having warm drinks. Can warm drinks be brought from the surface? They could easily be stored in a cooler full of very warm water before being brought down to you.
I hadn't though of that but it is a good idea. There is no reason why warm drinks couldn't be brought down in insulated hydration pouches.


Have you thought about weighting? Wearing a typical weight belt or other normal weighting systems would kill my back. I would try to work out a weighted or fixed platform, and then wear a typical BP harness (with a bunch of extra D-rings mounted on it) and then have numerous attachement points from which I could clip myself off to the bottom. Thus you would be floating slightly above the bottom. I think you might want removable ankle weights and possibly a weighted backplate and maybe even some weight belt(s).
All good ideas. Due to the large amount of insulation I'll be wearing under my drysuit, I'll need a lot of weights. There will be a fixed platform with storage for food, a holder for tanks when in use, and a bed/chair that I will be able to clip my BP on to.

I also would not assume that wearing the primary tank on my back would be the optimal method.
I plan to have my primery tanks weighted and sitting on the platform with a long hose between the 1st and 2nd stages. I still would need pony bottles for dry suit and bc inflation closer to me though.

I would also plan on using manifolded double tanks as a gas source, especially if they will be laying next to you rather than wearing them. The bigger supply in doubles would make the logistic easier for you and top side support.
The problem with manifolded doubles is that they are much heavier for volunteers on the surface to deal with. A bigger problem is that all the equipment is being provided by sponsors. The tanks are being loaned to us by an LDS from their rental collection and I'm pretty sure they don't have enough doubles rigs for this dive if they even have any at all.

Also, I would investigate the potential benefit of breathing pure oxygen for the last 20 mintes of the dive to help eliminate nitrogen. Or possibly even have the last tank 50% oxygen and use that for an hour or so before ascending.
I plan to use EAN40 for the last two tanks of the dive. I will also breath pure oxygen directly after the dive for 15-20 minutes.
 
What about using Argon to fill your drysuit? That should drop your heat transfer by a bit.

I've seen at least one person in town, in real life, using an Argon drysuit fill.

You do have to be careful, as you'll die halfway through a deep breath of Argon.
 

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