Northwest Dive Club

So I have been reading as much as I can about areas related to diving that we are considering. One area I seem to have trouble finding good information on is decompression diving. I am not planning on reading a book and heading out to do it.

I would like to be able to read a book or web based facts (or as close as possible) about the theory of deco diving and even how mixed gas along with partial pressure effect it. I know the standard answer is probably "take a class" which is understandable before we actually do it. Right now I am just looking to understand it better.

Deco for divers by Mark Powell

Google is your friend

some ideas?

Scuba: How does tri mix work

information on deco diving

etc..

Lots of information out there.

Well maybe my google-fu has been weak.

The places I have seeing and reading seem to really skirt around details. There is a lot of talk about what it is but not how to actually do it or how it actually works. Most seem to come back and say "find and instructor".

I will say I do understand why some of this information is kinda guarded. No one wants to be the one where the "idiot" or the "I can lean it all by reading guy" goes out and gets hurt.

CaptnJack wrote:Deco for divers by Mark Powell

+1 bazillion!!

There is no other book better than this!! worth its weight in gold!

Its written in plain english for mere mortals and demystifies all those deep medical terms and complex physics algorithms, etc.

I loved this book, it also has all the technical details if you want it.. in fact, it has enough details in later sections (that you can skip if you want) to write your own deco planning software!!

seriously, best.. book.. ever!

Oh.. and go check your PM I hear koos-mas came early this year

And also, The Rubicon Foundation is your friend!

http://rubicon-foundation.org

LOTS of info there.

If what you are looking for is a book that will give you the precise execution for specific staged decompression dives, I don't think there is one. Deco for Divers will give you a ton of information about nitrogen dynamics and how decompression profiles are built, but even if you understand all the material, there are quite a few assumptions that have to be made by the diver, to decide exactly how the decompression for a given dive will be done.

I believe you can still buy the Ratio Deco online classroom from Unified Team Diving, which is probably the closest thing to a cookbook approach to deco that you will find, I think -- but it still makes assumptions, like what gas you are breathing, and the rough parameters of your dive.

If you are contemplating doing this, I would also HIGHLY recommend Steve Lewis's book,Six Skills and Other Discussions, which is available in a Kindle edition. It's very well written and quite useful, but it still won't give you a "Step A, Step B, Step C" approach to staged decompression diving.

Who wants to hang in cold, green water for a long time with nothing to look at anyway?

Blitz wrote:Who wants to hang in cold, green water for a long time with nothing to look at anyway?

Some guy named Nailer99 apparently.

I think the ringing of the hammer after all these years has made his head soft.

Blitz wrote:I think the ringing of the hammer after all these years has made his head soft.

I've heard the lack of hair for padding does that.

Another thumbs up for Deco For Divers - It will help you answer your question about "how it actually works" and the science (and history of the science) behind it.

About 3 months ago was looking for the same info that you're looking for so I could start getting ready for Tech 1. I was also a bit skeptical about Ratio Deco - It seemed a bit too simple - and wanted to understand what was behind it. I did the Google search for information on decompression diving/Ratio Deco and came up with either white papers that were way over my head or arguments on diving boards. Deco for Divers helped me understand what's behind the different decompression models and how they were developed.

The next step for me is to download a copy of V-Planner and simulate a few dives using various models and then comparing them to ratio deco profiles. This will help me start to answer the "how to actually do it" question.

FYI - GUE has some good material on ratio deco that they put on the internet - If you Google gue_ratio_deco you'll find it.

All great info and things I will look into.

Not looking so much at a "cook book" but some of the how's and why's. Something to give me more background.

Like one of the questions I have is how much deco do you are you obligated for after each min over NDL? I am sure it also has to do with depth and gas mix and is not a straight forward answer.

As i said when we are ready for that step we know where to find some great instructors

CaptnJack wrote:

Blitz wrote:I think the ringing of the hammer after all these years has made his head soft.

I've heard the lack of hair for padding does that.

Lies. All lies.


It's a combination of repeated head injuries and some poor choices involving mixing the wrong recreational drugs in my youth.

Nwcid wrote:All great info and things I will look into.

Not looking so much at a "cook book" but some of the how's and why's. Something to give me more background.

Like one of the questions I have is how much deco do you are you obligated for after each min over NDL? I am sure it also has to do with depth and gas mix and is not a straight forward answer.

As i said when we are ready for that step we know where to find some great instructors

Its as simple as this: depth plus time at depth equals deco. The deeper you go, and the longer you stay, the more it costs. The variables are endless after that. What gasses are you breathing? Cold or warm water? Are you a 29 year old triathelete or a 49 year old desk jockey who doesn't exercise?

What you need next is an algorithm, a formula, to calculate deco and allow you to plan. I have used vplanner for a long time, and it seems to work well for me.

I would urge you to take a class like advanced nitrox and deco procedures to really learn how to plan a deco dive safely.

The Navy Dive manual is a interesting place to read up on some of that as well.


http://www.usu.edu/scuba/navy_manual6.pdf

Nwcid wrote: Like one of the questions I have is how much deco do you are you obligated for after each min over NDL? I am sure it also has to do with depth and gas mix and is not a straight forward answer.

Not as much as you'd think. Assuming you are in the range where you have an NDL at all (<140ft or so) using air or nitrox.

My formula is the best one out there, Avoid it at all costs!

Dusty2 wrote:My formula is the best one out there, Avoid it at all costs!

Dive till it hurts, deco till it stops?

I dunno -- about the 25th minute in 43 degree water, deco HURTS!

kdupreez wrote:

Dusty2 wrote:My formula is the best one out there, Avoid it at all costs!

Dive till it hurts, deco till it stops?

When did you move to UTD?


>0]

defied wrote:

kdupreez wrote:

Dusty2 wrote:My formula is the best one out there, Avoid it at all costs!

Dive till it hurts, deco till it stops?

When did you move to UTD?


>0]

Heard it was a couple weeks after you did Fundies.

This thread is awesome

Jeremy wrote:This thread is awesome

Well they do say there is what you learn in the book/class and then there is the way it really works

lol

Yeah..I have deco for divers, not exactly light reading but not actuarial science either. I learned a ton from it. Great book.

I have yet to incur a deco obligation in my diving career. That's probably because I dive 32% in single steel HP 100's and basically just don't have enough gas to incur a deco obligation.

Someday though...deco will call my name.