The Fine Art of Decompression

[Munin]

I pay about $12 per 80 filling my own, using UHP helium. By topping off partial tanks it costs even less.

 

[SeaJay]

Where are you guys doing this? Do you all have your own fill stations?

 

[daylight]

Seajay,
It seems that you are kind of getting ahead of yourself.
Being a poster boy for Halycon can be fun up to a point. Wearing a BP/Wing while diving a single is cool, but then on one hand you are using backup light in leiu of a correct primary light and then talking doing Trimix diving, lets think it through. It 's great to be inquisitive and curious, but.........
FWIW, I suggest you develop a strategic plan for what are your diving goals. You need to br realistic and factor budget, physical, and lifestyle commitments into the equation.
When you enter into the technical realm, the cost of poker goes way up. Not only cost but risk. It's the real deal. Entering into a decompression obligation or overhead environment is a very measured step. You must ask, am I really ready for such a commitment, can I affoed it, and is it really what I want to accomplish?
Find a mentor and gain experience while being trained.
Please take this admonishment with the my best intentions for you.
Be Safe.
Larry

 

[SeaJay]

daylight once bubbled...
Entering into a decompression obligation or overhead environment is a very measured step. You must ask, am I really ready for such a commitment, can I affoed it, and is it really what I want to accomplish?

I think I'm okay in the commitment department.

Thanks for the advice.

 

[100days-a-year]

Having a fill station at home is not all it's cracked up.I can have a shop blow air over my UHP and O2,analyze and get within 2% .I have a unused compressor in my garage due to $2 air and 3$ nitrox fills at the LDS.For more extreme adventures buddy #1 has a full mix station in his house.Daylight's suggestion of a written goal sounds like he has walked the walk.Impulsiveness is often expensive in SCUBA .

 

[Doppler]

SeaJay once bubbled...


I think I'm okay in the commitment department.

Thanks for the advice.

Seajay: Whether you opt for a specifically branded type of hogarthian dive training or not, you sound like you have a strong desire to learn and learn correctly. Which is great since you already know the #1 cause of dive accidents.

From what I've read of your past postings, I am a little surprised you have not got more experience planning decompression dives. No problems. Proves you're not full of BS. You have the balls to admit what you don't know.

I would suggest that you continue your "information gathering" by sitting down with v-planner, read the instructions, and throw in a few profiles and try to understand the face of the algorithm. It'll help you grow your confidence.

The major difference you will find diving that type of profile -- compared to a Buhlmann model -- is that it is unforgiving of ****-ups deep in the water column. Make your ascents at the prescribed rates -- horizontal -- and make any gas switches ON THE BUTTON. Also, always dive well hydrated and with enough knowledge to bail out with grace.

Someone you know and respect told me once to always start a Decompression Class by telling everyone in it that they are nuts. The risk is elevated. He was right. Training and experience diving (not in a pool in real world conditions) helps us to manage that risk.

Good luck.

PS you might wanna get a copy of the Oxygen Hacker's Handbook

 

[SeaJay]

Thanks a lot, Doppler. I really appreciate that...

Looking into all of that stuff now...

 

[Richeod]

Judging from your commitment to DIR I would NOT recommend that you train with any agency besides GUE simply because to fully understand DIR you need more than a Fundamentals class. Nothing amuses me more than listening to so many people rant about DIR who have nothing more than internet experience. Once you get a few more GUE classes under your belt you will know what I mean. You will know because instead of trying to argue you will just laugh at what some people think is DIR. That’s why you see so many DIR divers drop off the board when the arguing starts.

As far as which class to take, my first thought was Tech 1. Tech 1 is nothing more than Rec TriOx with a stage, and deco theory plus the bar is a little higher. However after thinking about what you wrote in your posts I'm not sure that is still my recommendation. There is tons of information thrown out in a too short 5 days. Even if you show up with your skills in top shape I think (at this point) you may be too overwhelmed. I think that the Rec TriOx class is a better bet for you. It will allow you to stop and think about what is being taught rather than struggling to keep up. Later when it comes time to take Tech 1 a lot will be review but that never hurt anyone.

Why don't you PM MHK and ask him. He is a nice guy and would be glad to help. Always better to get it from the horses mouth.

Josh

 

[Razorblade]

Ok, so I downloaded and installed the V-planner because I was also interested.
I was plugging numbers in and seeing what came out. After a little while I realized that for shallow dives (say 30ft) no matter how long I put my bottom time, it never gave me a deco stop. I even put 800 minutes as bottom time, yet no deco stop. Can anyone explain that?

 

[Dr Deco]

Dear Razorblade:

NDLs and no deco - :scuba:

The no decompression limits NDLs give progressively longer bottom times the shallower you go. You will reach a point where the limits are essentially infinite and the depth at which this occurs is about 30 feet. It will depend a bit whether you are a diver or living in an underwater habitat.

What you have done is find the point in the v-planner algorithm at which there is never any decompression – about 30 fsw.

Dr Deco :doctor: