How much gas are you comfortable planning to leave a cave with?
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1800 psi
1500 psi
1200 psi
1000 psi
800 psi
500 psi
1200 psi, but if drills in the cavern, I'd come out with 1000 psi
1000 psi, but if drills in the cavern, I'd come out with 700 psi
other (explained in the comments part of the thread
Minimum gas I'd leave a cave with
How much gas are you comfortable planning to leave a cave with?
Land of Enchantment -- not so great for cave diving, but mighty scenic!
Other. Depends on the cave. I don't like to see less than 1000 psi, but that's nothing more than feeling too low.
"Those who make peaceful revolution impossible will make violent revolution inevitable." --JFK
depends on the cave and it depends on the tanks.
1000psi in AL80s is a different volume than 1000psi in 104s.
I marked 1200/1000 cavern but in reality, I normally exit the Florida caves with 1600 to 2000 on LP 85s or 95s. In the Mexican caves on AL80s, it is 1000+ On our last trip this year, we recalulated 1'3s on a couple of dives about 200 feet from OW. I think once I exited with less than 1000 and it was with 900.
Safe diving,
Sandy Robinson
Yeah, and not to mention when you finish your dive and there's this big ol' butt blocking your ability to get out of the cave, you have to reserve plenty of gas for that butt to get out of your way!Originally Posted by sandy
Land of Enchantment -- not so great for cave diving, but mighty scenic!
Only takes a little groping to move itYeah, and not to mention when you finish your dive and there's this big ol' butt blocking your ability to get out of the cave, you have to reserve plenty of gas for that butt to get out of your way!
Safe diving,
Sandy Robinson
Groping? I need to dive with some more fun folks! Y'all sound like a fun group!Only takes a little groping to move it
Jokes aside, it really depends for me. "Minimum" for me is in the 800psi range, but it has to be a very unique set of circumstances. For example: I was practicing for Full Cave and reel work was my weak-point. I ran the line into and out of JB dozens of times. Exiting after a bunch of those with 800psi wouldn't have bothered me. If I had exited after a "real" dive I would've not been quite as happy. I've done planned exits as low as about 1000psi (penetrated to thirds, turned, then explored stuff MUCH closer to the exit in JB when the flow was still high).
Oh, indeed! We are a very fun group!Block my way out of a cave, and I'm pretty much ready to grope almost anyone!
Land of Enchantment -- not so great for cave diving, but mighty scenic!
Whatever makes sense. Which Cave/Cavern? Cylinders? What was the fill (cooled or was it not even a cave fill)? What was the starting pressure? In reality, I'm way more worried about turn pressure. Risk falls with every foot closer to the exit that I travel. Is there deco? Do I have enough gas to deco out with lost deco gas? Buddy/Buddies? Heavily traveled like a busy day at Ginnie might all me to worry 10% less about triple failures, but also a MUST during the day/summer to plan for lost deco gas.
Just think it through; never plan for everything to go well, and plan for at least 2 failures and your buddy to be unreliable that day.
Have more than you need, not less, always.
definitely can't answer with anything but other. I dive PST HP120's most of the time, so the normal answer is 1200 unless I'm planning something. I.e. we are in a particularly nice cavern zone and want to dick around for a while and burn some gas, then I'll exit with generally about 500psi in both bottles, but I'm in the cavern zone, or at least beyond the sign, so not terribly worried about getting blocked in.
I also regularly dive LP72's, which means that I'm only starting with 2800psi max since I won't let them get filled higher than that, and they usually cool to 2600-2700. In that case, I expect to be leaving with around 900psi. I turn those at 1800psi regardless of fill, and I turn the 120's at 2500psi regardless of the fill, since Cathy doesn't give us over 3600 hardly ever, and 2500 is a nice number to see on the gauges. I am somewhat regularly the one with the lowest SAC and the smallest tanks unfortunately *this is compensated for gas matching*, and in the other scenario my buddy has a higher sac with HP100's, so he always hits turn pressure long before I do.
Can't put a number on it for all scenarios, but there's generalizations that tend to work. 1200 tends to be a good number, but with the springs flowing again, I don't think anyone has come out with 1200psi on a normal dive this year.
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