My AN/DP/Helitrox course

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Are you guys planning 3rds or halves on you deco bottles? I rarely use my 40s because 20cuft is just not enough on most of our dives.

It's pretty common my group to plan for ~90 minutes of deco and that puts me in the 30cuft range on O2. I'll likely use less, but this is the SAC I have chosen for planning.

For a two man team I prefer halves for deco gas. I can be talked into 3rds if we are a 3, but I will usually just plan halves since it's what's normal for me.
 
To get back to the actual primary purpose of this thread:

Good pool session today. Three hours. I was working by myself as tech instructor had a scheduling issue and had to work in the shop. I was in my 7mm as my drysuit is in the shop for the neck seal thing. Pool was 81F. I was damn hot. Kept having to let water into my suit. Much easier to reach valves, without drysuit neck ring, but not easy. Got better with some practice.

Worked on kicks and deco bottle handling skills, too.

I’d never been in doubles with a wet suit before and it was just weird.

And I got up the pool ladder from deep end twice with doubles on. Needed pulls on manifold, but I don’t care. This alone is major improvement. I’m putting in 45-60 min 3-4 times a week on the recumbent bike at the gym.
 
....Much easier to reach valves, without drysuit neck ring, but not easy. Got better with some practice....

There’s a PDF of a chapter from ‘workouts for divers’ or something of that title about stretching your shoulders. Just need some googlefoo to find it again.

Works wonders, spending that 5-10min in the morning stretching against a wall/door/outside corner/pole/etc and getting that flexibility.


_R
 
There’s a PDF of a chapter from ‘workouts for divers’ or something of that title about stretching your shoulders. Just need some googlefoo to find it again.

Works wonders, spending that 5-10min in the morning stretching against a wall/door/outside corner/pole/etc and getting that flexibility.


_R

I’m stretching. However original problems were from SiTech neck ring on my Fusion. I’m narrow shouldered and it really restricted my movement.
 
Are you guys planning 3rds or halves on you deco bottles? I rarely use my 40s because 20cuft is just not enough on most of our dives.

It's pretty common my group to plan for ~90 minutes of deco and that puts me in the 30cuft range on O2. I'll likely use less, but this is the SAC I have chosen for planning.

For a two man team I prefer halves for deco gas. I can be talked into 3rds if we are a 3, but I will usually just plan halves since it's what's normal for me.

Thanks for asking this. Following as well as I had the same question.
 
The issue with Al80's isn't when you're carrying one, it's when you're carrying multiple and the physical size/gas required ratio means you're carrying extra mass and physical volume for no gain. Stack 3 Al80's on your side and you can see how having two of them be Al40's would be beneficial. Obviously if you don't have access to more appropriate cylinders you make do with what you have.

For most deep bailout/deep deco, you're looking at higher volume required because of the depth. Once you get to your 50% and 100% bottle, you're shallow enough that you're not worrying about the gas volume, hence the preference for lower capacity, smaller physical size, cylinders, especially if you have to carry them the whole dive, or have to deco out in close quarters.


As for volume....

You don't plan 1/3rds or halves for your deco gas, you figure out how much volume you need to accomplish the dive and choose the appropriate cylinder based on that plus whatever you determine your reserves need to be. It's a conversation you need to have with your dive buddies in terms of lost gas planning. There are several schools of thought re-sharing deco gas, clearing yours then handing off, everybody stays on previous mix to keep the team aligned, etc. It may change based on the length of hang time too. You need to figure out what your plan is with your buddy based on the profile, the environment, etc. What could be as simple as sticking to your own O2 and your buddy on next richest until you're done with yours then hand off until he's done, to a three way split where each guy spends 10 minutes on, 10 off swapping O2 until everyone is clear, it all depends on several factors.

I know some rebreather guys that plan on a modified team bailout in situations where everyone carrying individual ideal bailout would be impractical, so everyone carries enough that if everyone has to bail, there's enough gas by volume, it just won't be optimal mix for every member of the team at all times. There's no one right answer.

Except 80% is a lame choice of deco gas. That one is certain.
 
Much easier to reach valves, without drysuit neck ring, but not easy. Got better with some practice.
Are you keeping your elbow close to your ear?

And I got up the pool ladder from deep end twice with doubles on. Needed pulls on manifold, but I don’t care. This alone is major improvement. I’m putting in 45-60 min 3-4 times a week on the recumbent bike at the gym.
Are you able to get up the boat ladder(s)?

Are you guys planning 3rds or halves on you deco bottles? I rarely use my 40s because 20cuft is just not enough on most of our dives.

It's pretty common my group to plan for ~90 minutes of deco and that puts me in the 30cuft range on O2. I'll likely use less, but this is the SAC I have chosen for planning.

For a two man team I prefer halves for deco gas. I can be talked into 3rds if we are a 3, but I will usually just plan halves since it's what's normal for me.
OC deco not CCR bailout right?
Only bringing O2 with a 90min obligation?
How much 50% do you have leftover in a pinch?
 
This thread is about 45m dives on a twinset. Most of those will need one deco gas so three 80s isn’t representative. Maybe you could start talking about caves but the OP is wreck diving.

The simple case of lost deco gas is the diver who is short does backgas deco until the donating diver is done and then takes their gas. That will work with halves, meaning you plan only to use half the deco gas normally, ie the cylinder has to be twice the size required normally.

How big that cylinder actually has to be will depend on the mix. Assuming the dive is gas limited, not cold, runtime or bladder limited, you can run Ross’s ‘Max Time’ feature of MultiDeco with your own preferred gas consumption rates, GF numbers and bottom gas. You will find that sometimes the bottom gas is the limit, sometimes the deco gas. With 50% it is likely the deco gas, with 100% the bottom gas.

All this kind of stuff is what people should be learning on a course like this. They need to learn what the various choices and compromises are so they can decide what to do for a given dive,
 
And I got up the pool ladder from deep end twice with doubles on. Needed pulls on manifold, but I don’t care. This alone is major improvement. I’m putting in 45-60 min 3-4 times a week on the recumbent bike at the gym.

Marie,

You might consider latissimus dorsi pulldowns, pull ups (palms facing away) or chin ups (palms facing in) and/or rowing to help strengthen the arm muscles you use when climbing up a ladder. I’m partial to rowing as it conditions the whole package (legs, lower back, upper back, traps, triceps and cardiovascular capacity). I’m also partial to TRX strap training as it uses your body weight to stimulate joint flexibility and muscular strength.

Granted, you should be using primarily your leg muscles (specifically, your quads) to come up the ladder. However, when holding onto the ladder in swell to take your fins off for a caged ladder OR when you Charlie Chaplin your finned foot out to the side to climb the Christmas tree ladder and the swell wants to take it away, you’ll need arm strength to keep you from falling off as the rocking of the boat works against the weight of your tanks.

Obviously, you’re not looking to join the meatheads at the gym banging plates and making prison noises, just waking up the muscles that have perhaps gotten dormant. I imagine there are some professional strength and conditioning coaches here or in your local area that will have more complete and vetted suggestions.
 
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