diving 1/6's
- Thread starter H2Andy
- Start date
Please register or login
Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.
Benefits of registering include
- Ability to post and comment on topics and discussions.
- A Free photo gallery to share your dive photos with the world.
- You can make this box go away
OP
H2Andy
Contributor
nah, i wanted to generate discussion on here
let me rephrase after all the numbers:
Dive 1: start with 3200 psi. dive 1/6 = 500 psi = 2700 turn. arrive back with 2200 psi
Dive 2: start with 2200. dive 1/6 = 300 psi = 1900 turn. arrive back with 1600 psi
or
Dive 2: start with 2200. dive 1/3 = 700 psi = 1500 turn. arrive back with 800 psi
dives 1 and dive 2 (using 1/3's) are almost identical in terms of penetration psi
and if instead of doubles i'd be wearing a single tank, dive 2 with 1/3's would
be acceptable WITH LESS GAS
let me rephrase after all the numbers:
Dive 1: start with 3200 psi. dive 1/6 = 500 psi = 2700 turn. arrive back with 2200 psi
Dive 2: start with 2200. dive 1/6 = 300 psi = 1900 turn. arrive back with 1600 psi
or
Dive 2: start with 2200. dive 1/3 = 700 psi = 1500 turn. arrive back with 800 psi
dives 1 and dive 2 (using 1/3's) are almost identical in terms of penetration psi
and if instead of doubles i'd be wearing a single tank, dive 2 with 1/3's would
be acceptable WITH LESS GAS
StSomewhere
Contributor
Sorry, your question makes total sense, I asked a similar question about the whole 1/6ths vs. 1/3rds thing to an instructor and was told that, up to intro, discretionary gives you the advantage of practicing with doubles but only with the pentration limits for intro, which is at the heart of the rule. I then got the "safe attitude"/"don't lawyer-up the rules"/"what's the spirit of the rules?" lecture, which I took to heart. Which is ironic, considering I'm not a lawyer. 
Edit: What I decided to do was work towards intro this summer with singles, and only after mastering that will I begin to move onto doubles. Interesting that when I came to this answer for myself that I knew it was the correct path for me. You are obviously on your own path, which is why I asked you to ask your instructor.
Edit: What I decided to do was work towards intro this summer with singles, and only after mastering that will I begin to move onto doubles. Interesting that when I came to this answer for myself that I knew it was the correct path for me.
You are obviously on your own path, which is why I asked you to ask your instructor.
OP
H2Andy
Contributor
hey, i *am* a lawyer, but a wus... so i intend to read the rules literally
and dive 1/6 of my total gas
(but i already found a way around that)
(which is to refill after every dive)
and dive 1/6 of my total gas
(but i already found a way around that)
(which is to refill after every dive)
StSomewhere
Contributor
Heh heh, I knew that.H2Andy:
Which is what Jason was saying about the minimum starting pressure. The ideal is two sets of doubles, but MAN that is some serious expense! :11:H2Andy:
scubafool
Contributor
Andy, here is my answer.
While some say that the 1/6 rule is to limit penetration, I look at it differently. The reason that I did my Intro class in doubles was to get my instructor's approval to Intro dive in doubles, so that I would have a larger reserve to deal with problems. 1/3 of a single 100 is obviously 33 1/3, and 1/6 of double 100's is obviously 33 1/3, so the difference is in the reserve gas. Reserve with the single is 66 2/3, and with the doubles is 166 2/3. MOST Intro divers are relatively new to cave diving, so we have relatively little experience with the cave enviroment & the problems that it can contain.contain. Therefore, I would think that a much larger reserve at this level of cave diving would be wise. Therefore, I chose to do my Intro class in doubles. Changing the 1/6 rule on your second dive to 1/6 of the first dive's gas supply denies you the benefit of the 1/6 rule.
While some say that the 1/6 rule is to limit penetration, I look at it differently. The reason that I did my Intro class in doubles was to get my instructor's approval to Intro dive in doubles, so that I would have a larger reserve to deal with problems. 1/3 of a single 100 is obviously 33 1/3, and 1/6 of double 100's is obviously 33 1/3, so the difference is in the reserve gas. Reserve with the single is 66 2/3, and with the doubles is 166 2/3. MOST Intro divers are relatively new to cave diving, so we have relatively little experience with the cave enviroment & the problems that it can contain.contain. Therefore, I would think that a much larger reserve at this level of cave diving would be wise. Therefore, I chose to do my Intro class in doubles. Changing the 1/6 rule on your second dive to 1/6 of the first dive's gas supply denies you the benefit of the 1/6 rule.
Andy,
Why not finish full cave and just go diving? You have the gear. Can you get off 4 days in the next few months?
1/3 will never equal 1/6, so you would not be diving at the intro level on 1/3's.
Why not finish full cave and just go diving? You have the gear. Can you get off 4 days in the next few months?
1/3 will never equal 1/6, so you would not be diving at the intro level on 1/3's.
OP
H2Andy
Contributor
Divesherpa:
i figured i'd get some more dives in, build up experience, then move on to apprentice
sometime next year. i hope to get full cave by 2007
scubafool
Contributor
H2Andy:
Don't you think that you are pushing it a little, LOL?
OP
H2Andy
Contributor
:17:
Similar threads
