Need examlpes

[Darian Dunn]

Fist things first: Legal note: I am responsible for my own actions and will not be using any examples to do any real dives.

I am reading the GUI fundamentals books. Maybe I am unusual, but a practical example of how and when to use the different mixture would go a long way to helping me understand when to use what.

What I am looking for is, what gas mixture you use, at what depth for how long going downa nd comming back up.
If you use different tables of formulas along the way please note when and why they were used (i.e. Nitrox to equivalent air table, then PADI dive table1).

Can someone please send me (I understand why you would not want to post to an open board) a “technical” dive profile?
Darian_Dunn@stercomm.com

Thanks

 

[Friggincold]

you tell us depth and time we may be able to help...FC

 

[Okiecaver]

=-) Don't want much do ya?

I plan my mixes on 3 things
1- team standards. We all use standard bottom and deco mixes to avoid ugly surprises when air sharing
2- pO2. Need to keep that to a reasonable minimum to avoid CNS complications
3- END. GUE standards are 100 ft. I shoot for 70 ft cause I'm a wuss about narcosis. That means a minimum of 35% helium in my mix.

Custom tables are cut for every dive.

This weekend I'm doing the Open Water portion of my trimix cert at Table Rock. Should be fun!

dive safe
Brock

 

[Darian Dunn]

I guess I didn’t word the question correctly.
I know for most recreational diving Air is good down to 100ft.
If I want to stay down longer I would use Nitrox. I am Padi Nitrox certified. For all the recreational diving I do, I could dive Nitrox all the time.

My question is when do you use “other” mixtures?
If you were going down to 150ft, would you want to use nitrox down to 110ft or something else?
Why would you want to use Oxygen at the last deco stop at 20ft?

I know am missing something obvious, but I just don’t get it.

 

[Lost Yooper]

Believe it or not, this is a very loaded question. There are a lot of variables that play into this stuff.

If you get beyond 100' or so, it's a good idea to be on trimix. Use nitrox up to 100' and stick with standard gasses.

As for O2 at 20', it allows you to offgas much quicker than on backgas. The deeper you go and the longer you stay, the more deco gasses you may take with you. The next gas in line is 50% nitrox at 70'. When or how you choose to incorporate deco gasses is dependant on many factors. I often use only 50% at 70' so I offgas early in the dive. Some guys only use O2. It's a cost/benefit thing sometimes.

Ask some specific questions.

Mike

 

[omar]

The GUE recommended standard mix for 150' is 21/35.
I would typically use 20/40 for this. I use 30/30 for 70-120; 20/40 for 120-165; 17/45 for 165-200. However, the mixes are the same for all divers in the group. If the other guy(s) were using 21/35 I would also.

For these dives I use 50% at 70'. This is to take advantage of the oxygen window earlier and to stay away from a "bend and treat" profile/gas use which is what you would get with a dive to 150 and using O2 only for deco. For a dive to 150 I would choose an appropriate profile/BT where only one deco bottle is needed.

You can breath these mixes from top to bottom. I would recommend that you do not huff on the 17/45 for any length of time at the surface.

omar

 

[Waterlover]

All kinds of things come into the dive planning. Some things others have not mentioned, multipe dives over multipe days,work load, water temp, cave or open water.
Deco mix for me is standard 50/50 and 100% for dives less than 200 Bottom mixes and deco schedules vary based on the other factors mentioned. Typical guidelines for me are PO2 1.4 or less usually around 1.2 Deco <1.6. Backgas breaks every 15 for 5 during deco(subject to change this year). Ask the questions we'll try to answer.
Ken

 

[Wendy]

Why don't you take GUE tech 1 or a trimix course and then you will find out when to use what and why. I don't know your current cert so I'm not that comfortable with giving out 'what to use' advise.

 

[Darian Dunn]

I am not to the part when they start using #/# notation or I missed something.
Which gasses are you notataing? O2 and He?

 

[Darian Dunn]

Wendy, I understand.
Currently reading the GUE Fundamentals of Tech diving book and I am ending up with more questions than answers. The other GUE fundamentals book is on order.

I understand there are alot of differnt mixes. What I am not sure of is why you would use which different mix.

To be honest, if I could understand one dive. I think I would understand more of the big picture.

I do not plan on diving on this informaion. That would be just stupid.

BTW, I am really considering taking the GUE fundamental in Michigan in June/July (time and money permitting).