Uncle Pug
No wonder Helium is in such short supply your using it all up on shallow dives
No wonder Helium is in such short supply your using it all up on shallow dives
Deep Air medical question(s)
- Thread starter dc4bs
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Yo AquaTec,
I don't know what you guys have to pay for the good stuff up there in BC but I've got a contract price on HP here for $45 a T so it really isn't that bad. Shop around and don't settle for the first price they quote you.
As for the air.... I have to admit that when we ran through the batch of mix we took with us to BC last weekend that we dove air the last day (but nothing below 100')... and I felt crappy the whole way home. Part of that was the terrific cold I was suffering with but the air hammered me.
Oh... and sorry about leaving nothing but the dishes in that other thread... when they started with the questions I knew that was going to happen... and I felt real bad that you had to be gone at work
I don't know what you guys have to pay for the good stuff up there in BC but I've got a contract price on HP here for $45 a T so it really isn't that bad. Shop around and don't settle for the first price they quote you.
As for the air.... I have to admit that when we ran through the batch of mix we took with us to BC last weekend that we dove air the last day (but nothing below 100')... and I felt crappy the whole way home. Part of that was the terrific cold I was suffering with but the air hammered me.
Oh... and sorry about leaving nothing but the dishes in that other thread... when they started with the questions I knew that was going to happen... and I felt real bad that you had to be gone at work
I pay about $95.00 for the same, which is about $50.00us +/-
about the 32% thats cool I like that it stimulated what I consider intelectual conversation. [even if i can't spell it]
and I see some of your points but not all of them
about the 32% thats cool I like that it stimulated what I consider intelectual conversation. [even if i can't spell it]
and I see some of your points but not all of them
Not all of the points are ironclad stand alone reasons for using 32%....
Just taken together (with the ones I am forgetting) they present a case for 32%....
The key from my POV is using a standard mix... and the economics favor the EAN32
[I us spel ckek]
Your cost analisis was a good learning thing for me. I had never figured it that way before.
32% for a dive mix I see it your way and it makes since.
As for a deco gas I would use as high a PPO2 as possible based on the dive frofile, I would say that 36% is my standard mix for this, but we are splitting hairs here
32% for a dive mix I see it your way and it makes since.
As for a deco gas I would use as high a PPO2 as possible based on the dive frofile, I would say that 36% is my standard mix for this, but we are splitting hairs here
We're off the thread here a tad but it is at least tangent to the original discussion so:
Shane and I are not doing any dives that we need other than the (DIR standard) 70' (EAN50) and 20' (O2) deco gases. The idea of the EAN 50 is to open the oxygen window for 3~5 minutes at 70 for any dive that requires other than minimum deco.
Well there you go you are using as high a PPO2 as possible
I choose 36% to get on it sooner and you choose 50% to get the higher dose all be it shallower.
Same princibles just different methods.
So now I ask why 50%, is it because it generaly represents your first deco?
are you decoing on back gas prior to that?
I have been taught to get off He asap, [that view point is changing thanks to information recieved from guys like yourself]
Yes we are off topice hope that is OK
If someone wants to jump in here back on topic, i will stand down my sponging up info
I choose 36% to get on it sooner and you choose 50% to get the higher dose all be it shallower.
Same princibles just different methods.
So now I ask why 50%, is it because it generaly represents your first deco?
are you decoing on back gas prior to that?
I have been taught to get off He asap, [that view point is changing thanks to information recieved from guys like yourself]
Yes we are off topice hope that is OK
If someone wants to jump in here back on topic, i will stand down my sponging up info
I can only tell you what I have been taught so far and please understand that I am not aware of all the nuances that go along with DIR....
But I am learning that there seems to be a valid reason for each of them when I finally get to the end of the learning curve on a topic....
While at times 70' is the first deco stop called for by our tables it is not the first one we do....
We add in deep stops starting with 80% of the ATA of max depth.
There is a rule of thumb for this but 80% is published standard.
Prior stops are on backgas.
Helium is our friend.
Deeper/longer dives than we are doing require an additional deco gas but I cannot speak to that.
Uncle Pug
Quoted by UP "I can only tell you what I have been taught so far and please understand that I am not aware of all the nuances that go along with DIR....
But I am learning that there seems to be a valid reason for each of them when I finally get to the end of the learning curve on a topic.... "
I am finding out the same, I am just further behind you
OK lets go to the 80% rule.
A dive to 11ata [330fsw] for say 15 minutes, you first deco stop is 8.8ata [257.4fsw] correct were is your next deep stop.
I will tell you how I have done this, I got this from reading variouse papers on the subject one of which was published by Richard Pyle. it is just my way
same dive all things being equal my first stop with the gas i chose etc would be at 130fsw.
So I take difference in depth between 130 and 330 = 200 devide that by 2 and get 100 I get 130 plus 100 = 230 for the first stop
then the same process again 130 and 230 = 100 / 2 = next stop 180 carry this forward until you hit your first asigned deco stop
[hope i made since here]
The 80% rule. why is it a rule and how do you get the next stop
Quoted by UP "I can only tell you what I have been taught so far and please understand that I am not aware of all the nuances that go along with DIR....
But I am learning that there seems to be a valid reason for each of them when I finally get to the end of the learning curve on a topic.... "
I am finding out the same, I am just further behind you
OK lets go to the 80% rule.
A dive to 11ata [330fsw] for say 15 minutes, you first deco stop is 8.8ata [257.4fsw] correct were is your next deep stop.
I will tell you how I have done this, I got this from reading variouse papers on the subject one of which was published by Richard Pyle. it is just my way
same dive all things being equal my first stop with the gas i chose etc would be at 130fsw.
So I take difference in depth between 130 and 330 = 200 devide that by 2 and get 100 I get 130 plus 100 = 230 for the first stop
then the same process again 130 and 230 = 100 / 2 = next stop 180 carry this forward until you hit your first asigned deco stop
[hope i made since here]
The 80% rule. why is it a rule and how do you get the next stop
I don't dive to 330' so I can't give you first hand knowledge on the deco for that dive.... however I know what I have read from G3 about decos for that dive and it follows with what I have been taught for dives to my level.
The rule is not a *law* but a *rule of thumb*.....
There are short cuts to figuring deco in DIR.....
These allow you to make adjustments when necessary.....
The 80% is not even the real short cut.... there is a shorter one....
The next stop is figured not as a stop but as part of a curve....
The rate of ascent coupled with a brief stop every 10 feet gives you the curve....
The length of the stop changes the curve....
This sounds rather cryptic I know but the dives you are doing are way beyond what I am doing and I really think you would (of all the people here on this board so far) benefit greatly from GUE's Tech courses.
Not only would you learn their nuances of deco but I think you would learn that they have a truck load of other stuff to make your UW explorations successful.
In short... you would really dig it
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