Dive computers & brains.

[Finless]

Whislt replying to a post on Divernet to do with "Cochran Dive Computers, replacement straps and using bungee instead" I followed a link (below) to a DIR site where the following statement was made in the "official material"

"........ OK computer, but I use it in gauge mode as the only reliable  computer  is  the  one  between  your  ears."

Given the possibility of narcosis, maybe stress, straying attention (photography etc)  - it seems to me, from my point of view, that this is a totally misguided opinion. Great if you can do the deco etc "on the fly" but why not at least leave the computer on so if YOU/HE has a problem ......

I am obviously missing some information on why this statement was made. Even out of a diving situation people "do the funniest things".

As previously stated in other posts I am not interested in causing or being involved in a ruck but seek more information.

Because the source of the material is DIR (stress on Right) I often wonder if I am missing something in relation to the reason for reaching a conclusion if I disagree with it.



LINK

[Dominic]

I think that's more about the brain not needing rebooting or regular battery changes than about saying people don't make mistakes

[Finless]

Originally Posted by [b

Quote[/b] (Dominic @ April 07 2004,12:53)]I think that's more about the brain not needing rebooting or regular battery changes than about saying people don't make mistakes

Ah. But surely there is no diff to using the computer just in guage mode. If the battery runs flat it has the same effect in whichever mode being used.

Computer failure - still has the brain as backup?  

I'm sure there is some basic fundamental difference in the mentalities of DIR and other divers. I guess that at least there is some diversity left in the gene pool.  

[adam]

Hi,

Once again, I am keen to avoid a ruck- and will explain only why my computer is in gauge mode permanently-if you want to rely on one, please do so! Remember DIR and diving styles are about personal choice-if mine are different from yours that's fine!

To be honest, my reluctance to rely on my computer's model is less to do with potential failiure than it is to do with the issue of dependency. I am unwilling to rely on any one piece of equipment for crucial answers such as my deco schedule. This is compound by the fact that I don't need one! The "big computer" provides (with some pre planning) all the info I need. It also allows me to easily incorporate changes-in terms of how deco affects me, and in terms of my dive plan, with ease. My back up in the event of problems is what is between my ears, not on my wrist!

I have not heard (and I may be wrong) of a wrist computer model that incorporates some of the elements that I consider crucial and have prioritised in my own approach to deco. These include deep stops that are effective, allowing for the opening of the oxygen window, proper elimination of inert gas by using gradient at shallow stops and allowing me to toggle mixes to deal with CNS toxicity, and maximise gradient. Although I'm sure it is possible to build a model that will incorporate these things-the fact is that I still don't need it!

The answer to your questions doesn't lie simply in a series of ideas about deco theory, or instrument fallibility. The use of computers (or lack thereof!) by DIR divers is another element in a complete system. I know "holistic" is not a popular word, but in order to understand many of the decisions made by DIR divers, I'm afraid it does apply. I'm not trying to exclude people, please use whichever parts of the system that will work for you, but the system works best when used "whole"

The core of DIR philosophy is not about equipment, but about situational awareness. This is about mananging 3 variables-equipment, team and environment throught the dive. In truth this is where you will find most of the answers to the potential problems (and others) that you have listed.

You mentions concern about narcosis-I manage this by using gas mixes that ensure that I am not suffering from undue narcosis! This again causes problems with most computers-few of them can handle/deal with Helium in a way that works for me.

In a team, one member is designated to "manage" the deco-it is their task to ensure that everyone has left the bottom, and does the correct ammount of deco. He or she makes this their primary task-providing back up for others who might be engrossed! Please bear in mind that each team member has the same responsibility for situational awareness-so the "deco manager" should only be a back up, people should leave the bottom on time!

Stress is a more subjective issue, but once again, having a team is a great help! Gas choices, standardised equipment and gas mixes, physical fitness, standardised responses to problems, and many of the other parts of the DIR philosophy help reduce stress, but for me, the crucial element is practice! I spend as much time as I can in the water-doing drills over and over, building muscle memmory, and hence giving myself confidence in my ability to manage situations!

I'm sorry that this post is so long! I didn't intend it to be! (that wasn't very DIR was it!). All diving styles are based on personal choices-my long winded attempt to answer your questions is not an attempt to persuade anyone to become DIR or to leave their computer in gauge mode(!), only to give you an idea as to why I do so. I hope it helps

Adam

[Finless]

Adam,

Originally Posted by [b

Quote[/b] ].....and diving styles are about personal choice-if mine are different from yours that's fine!

Couldn't agree more + you are correct about the word holistic now being one that causes me irritation when I hear it.

Good explanation and I can see "where you are coming from". Tks for taking the time over your reply.

Bryan

[scubadog]

On the issue of replacing computer or bottom timer straps with bungee, according to George Irvine, It is not recommended. As the strap could be used if you rip a seal on your drysuit.

Info from DIR-diver.com

[torbaydiver]

I use neither  

[bang-on]

<font color='#0000FF'>

Originally Posted by [b

Quote[/b] (adam @ April 07 2004,14:31)]I have not heard (and I may be wrong) of a wrist computer model that incorporates some of the elements that I consider crucial and have prioritised in my own approach to deco. These include deep stops that are effective, allowing for the opening of the oxygen window, proper elimination of inert gas by using gradient at shallow stops and allowing me to toggle mixes to deal with CNS toxicity, and maximise gradient. Although I'm sure it is possible to build a model that will incorporate these things-the fact is that I still don't need it!

adam,
interesting post and gue is obviously working well for you.
the vr3  i use fills the criteria listed above and thats why i use it 'my choice' as not using one is yours.
what i wonder about is this........
during a dive on ccr to 70 mts planned for 20 mins bottom time its becomes necessary to do 47 mins bottom time and your ccr now requires you to 'bail to o/c' for the ascent and deco.
how do you mentally track your cns and deco and deepstops etc as well as deal with a stressfull situation.
part of my reasoning for using a vr3 is to deal with problems and situations without having to mentally work out stops etc when the shit has hit the fan and a casualty maybe involved is it not better to reduce task loading rather than increase it.

cheers
barrie

[Dominic]

DIRers wouldn't be on CCR in the first place

[bang-on]

Originally Posted by [b

Quote[/b] (Dominic @ April 07 2004,21:17)]DIRers wouldn't be on CCR in the first place

<font color='#0000FF'>rb 80 ??