500 psi for two divers?

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if I was running a charter where the planned depth was lower than 60ft they wouldn't be allowed on said boat, you need a certification that says you are trained to the requirements of that dive. You are not trained to dive beyond 60ft so say PADI themselves, ergo you won't dive beyond 60ft under my supervision unless I am your instructor training you to dive deeper than that. This is what I don't get by your points, they clearly say you are trained to a maximum depth of 60ft, so who in their right mind would allow you to dive deeper than that and run the risk of a lawsuit if something happened. This circles all the way back around to the lawsuit involving Wes where he was an idiot and his wife is now taking legal action and the lawyers took the manufacturers of the gear into the lawsuit. Another case where a military colonel took a student into a cave, they got the key by saying they were taking the trash out, they both died. The guy who owned the shop PRIOR to the current owner of said shop who had the keys was sued. Ask a lawyer what that paragraph would mean to them if they were prosecuting.

The or shallower is irrelevant to the point because it was pertaining to limits, so obviously up to your training limits aren't relevant.

Removed experience because it says "AND training" and the fact is that experience is oft ignored in place of training which is part of the problem, why on earth does PADI brag about divers getting certified and then teaching less than a year after their initial certification. Where's the experience there boys?
 
I'm just curious, where did the value of 500 PSI become such a key metric? A lot of SPG mark it in red, we're told "exit with 500 PSI", etc. Does it have any relationship to the old "J" type valves, where at appx 500 PSI you were "OUT" and then you pulled the reserve rod down to get to the rest of the air. (unless the rod had gotten snagged on something and pulled itself down already). I vaguely remember them from when I first did some diving, but perhaps one of the old timers can help me out on this.

Steve

The J valve on a steel 72 or AL 80 is designed to warn a diver at 500 psi. Realize it didn't instantaneously shut it off, but gradually increased the inhalation effort, so depending on how your SAC was you could breath a tank below 500 psi before getting enough restriction to realize you were low. Which might mean instead of it being 500 psi it was 400 or 300 psi.
Back then 60 FPM was the standard ascent rate and the safety stop was yet to be taught. I have done 60 FPM ascents from 80 feet beginning at 300 psi and arriving at the surface with 200 psi. This is a straight up ascent, not a sloped ascent up a line. If you screw up then the objective is to get to the surface, line ascents are nice but straight up is shorter, and safety stop be dammed.
 
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The J valve on a steel 72 or AL 80 is designed to warn a diver at 500 psi. Realize it didn't instantaneously shut it off, but gradually increased the inhalation effort, so depending on how your SAC was you could breath a tank below 500 psi before getting enough restriction to realize you were low. Which might mean instead of it being 500 psi it was 400 or 300 psi.
Back then 60 FPM was the standard ascent rate and the safety stop was yet to be taught. I have done 60 FPM ascents from 80 feet beginning at 300 psi and arriving at the surface with 200 psi. This is a straight up ascent, not a sloped ascent up a line. If you screw up then the objective is to get to the surface, line ascents are nice but straight up is shorter, and safety stop be dammed.

Way to go old guy, we're contemporaries. What about when breathing got difficult and you discovered that your J-valve had already been pulled by kelp or whatever. Ascent to the surface was still infinitely doable or I would not be here posting today. SPGs made everything must safer, I had my 1st in 1972. My memory is that J valves kicked in at about 300 psi, maybe my memory has suffered over the years.
 
Ya, really bad feeling when you reached back to pull your J Valve and it was already down.

Ru Ro...... Pucker power.... And the Octo haven't been invented yet on your buddy's rig.


Sent from my iPhone using Tapatalk
 
if I was running a charter where the planned depth was lower than 60ft they wouldn't be allowed on said boat, you need a certification that says you are trained to the requirements of that dive. You are not trained to dive beyond 60ft so say PADI themselves, ergo you won't dive beyond 60ft under my supervision unless I am your instructor training you to dive deeper than that. This is what I don't get by your points, they clearly say you are trained to a maximum depth of 60ft, so who in their right mind would allow you to dive deeper than that and run the risk of a lawsuit if something happened. This circles all the way back around to the lawsuit involving Wes where he was an idiot and his wife is now taking legal action and the lawyers took the manufacturers of the gear into the lawsuit. Another case where a military colonel took a student into a cave, they got the key by saying they were taking the trash out, they both died. The guy who owned the shop PRIOR to the current owner of said shop who had the keys was sued. Ask a lawyer what that paragraph would mean to them if they were prosecuting.

The or shallower is irrelevant to the point because it was pertaining to limits, so obviously up to your training limits aren't relevant.

Removed experience because it says "AND training" and the fact is that experience is oft ignored in place of training which is part of the problem, why on earth does PADI brag about divers getting certified and then teaching less than a year after their initial certification. Where's the experience there boys?

It's so cute to watch non-lawyers wave around the litigation risk banner with such gusto.
 
Way to go old guy, we're contemporaries. What about when breathing got difficult and you discovered that your J-valve had already been pulled by kelp or whatever. Ascent to the surface was still infinitely doable or I would not be here posting today. SPGs made everything must safer, I had my 1st in 1972. My memory is that J valves kicked in at about 300 psi, maybe my memory has suffered over the years.

You are right single 72's were 300, double 72's were 500
 
Your J valve has already been tripped.. How often do you check your SPG?

Below is a 7 second video on how to correct that:

[video=youtube;KQeKQMV7gck]https://www.youtube.com/watch?v=KQeKQMV7gck&feature=youtu.be[/video]
 
Ya, really bad feeling when you reached back to pull your J Valve and it was already down.

Ru Ro...... Pucker power.... And the Octo haven't been invented yet on your buddy's rig.


Sent from my iPhone using Tapatalk

... but we knew buddy breathing
 
Lecter, only because I've seen people sue dive ops for stupid reasons first hand and since this day in age you can sue for damn near anything, I'd rather CMOA.

Why did 2 divers perish in central Fla. underwater cave? - Jackson County Floridan : News

That's the referenced lawsuit from cave country. The widow sued the prior owner of Scuba West who had never met the guy. Obviously it didn't go anywhere, but it was 3 years of hassle until the judge finally removed him from the case.
 
Getting back to the initial post for a moment, I'm going to pose some things for the OP to think about ...

1. Unless you've practiced it more than that one time in OW class, do not assume that you'll be making a direct ascent while holding onto another diver and sharing air. The reality is that you'll be struggling to control your buoyancy and will most likely be doing a lot of ups and downs while trying to control your ascent rate. It will take a lot longer to get there than you might think.

2. Both of you will be stressed, and stress makes your breathing rate increase ... you'll be going through that tank a lot faster than you would if you were just breathing it under normal circumstances by yourself. My measurements with students under stressed conditions over the past 10 years suggest that the average diver will roughly double their breathing rate under stressed conditions ... and in some cases that rate increased by a factor of four!

3. Safety stops are optional ... breathing is mandatory. Prioritize, prioritize, prioritize! Getting to the surface is ... by a WIDE MARGIN ... your top priority.

4. Even if you were to somehow manage to get bent by skipping your safety stop, that condition is fixable. If you were to run out of air at safety stop depth and drown, the result will most likely be death, which is an unfixable condition.

The answer therefore is a no-brainer ... do not stop. Go directly to the surface, Inflate your BCD as soon as you get there, and if for any reason you have insufficient air in your tank to inflate your BCD, DROP YOUR WEIGHTS! Remember, the person who is out of air will be unable to inflate their BCD, so if they cannot manually inflate while remaining on the surface, they should also DROP THEIR WEIGHTS!

For new divers and those divers who don't dive very often, I recommend practicing these skills in a pool or somewhere in relatively benign water ... sharing air, ascending while sharing air, manually inflating BCDs, and dropping weights while at the surface. The reason is simple ... like every other skill you use in life, they become easier with practice. And in times of stress, you WANT them to be as easy to perform as possible ... it's unlikely in the extreme that you'll have the mental bandwidth in an OOA situation to think back on what you learned in OW class if you haven't practiced it, and performing these skills in a timely and relatively calm manner is critical to ending this dive without it becoming a real emergency.

Final thought ... a real OOA situation is nothing like what you did in class. You won't have time to mentally prepare ... it will come as a total surprise, which you must react to relatively quickly. You also will most likely not have the ability to take that last complete breath off your regulator like you did in class ... you may therefore find yourself already in an air-deficient condition at the time the OOA happens, which makes a prompt OOA response rather critical to a successful outcome. This is where personalities come into play .... how prepared are you to react calmly to a surprise, emergency situation? It's best to know the answer to that question before you ever find yourself in a position to have to find out ...

... Bob (Grateful Diver)
 

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