planning a deco dive

[CD_in_Chitown]

I haven't run the numbers, but apparently 60m is within meters of a PPO of 1.6. And, although its highly diver specific and apparently higher PPOs can be "worked up" to, 1.6 is the reccommended limit for the RESTING part of a dive, not the working part.

60m = 200 fsw

218 fsw on .21 (Air) = 1.6 PO2

Careful with the reccommended limits, your agency and mine might disagree.

DON'T DIVE BEYOND YOUR OWN LIMITS, JUST CAUSE YOU CAN DOESN'T MAKE IT SAFE.

To the OP, 60M is a lofty goal. I have been building toward deeper diving for a few years and haven't cracked 50M yet. Patience on the path, education will get you there.

 

[espenskogen]

DON'T DIVE BEYOND YOUR OWN LIMITS, JUST CAUSE YOU CAN DOESN'T MAKE IT SAFE.

To the OP, 60M is a lofty goal. I have been building toward deeper diving for a few years and haven't cracked 50M yet. Patience on the path, education will get you there.

Well said, CD

 

[CD_in_Chitown]

I saw how they crucified you and figured I better harden my tone some

 

[Wijbrandus]

I'm just amazed this thread is in the "BASIC" scuba discussion.

And I'm surprised at how nice everyone has been to the OP. I thought for sure this would have been a flame-fest. (And in my opinion, rightly so.)

Sorry, OP, but your reasons for wanting to do this are pretty crazy to me.

 

[Rick Murchison]

Me and a friend have been discussing doing a deep dive to perhaps 60 metres on air. I realise this is fairly dangerous but not unheard of. Our reasons? Just to see what happens really. My deepest previous dive has been to 40m.

Can somebody point me in the direction of an informative site or thread where this has been discussed?

much appreciated

There's a vast difference in 40 and 60 meters depth. Narcosis, nitrogen and oxygen loading, decompression status, gas supply and bailout options all converge to make such a dive "suddenly" a great deal more than "just another 20 meters deep." The bottom line is that you can probably get away with it, but if anything goes wrong, like, say, a freeflow at depth, you're in deep trouble, and quickly.
I recommend formal training... due diligence demands it
Rick

 

[espenskogen]

You mean there's actual training for the baseball bat stunt???

You're not suggesting you'd go do such a complex stunt without any training, do you?!?!

I wonder what the DIR way of doing that stunt would be? No labels on the bat maybe

 

[espenskogen]

I'm just amazed this thread is in the "BASIC" scuba discussion.

That's a good point - Maybe one of the mods could move the whole thread to the tech section?

 

[CD_in_Chitown]

The bottom line is that you can probably get away with it,

Once or twice maybe. But I could conceivably live through a sucking-gunshot-wound to the chest too, if the bleeding could be controlled, my friends reacted promptly to deliver first aid and summon resources, paramedics don't run into traffic, doctor isn't on the golf course, etc.

Nah, I got too much respect for Murphy to take those kinds of chances. Just not worth the risk.

 

[Hammerhead]

I know several Padi instructors who have done 120 meters on air.

First off, I don't disbelieve you, I'm out of touch with the air dives being done now.

On t'other hand, I know (and dive with), a bunch of guys who dived with the late - and much missed - Jon Bennett. These people, one of whom I now work with, did a series of push-the-limit dives to breach 100m on air (with doubles, redundancy etc. etc.etc.).

This is not really that long ago, and these same guys were training / skill building to assist on world record attempts. The deepest, and in optimum conditions, was 110m.

Again, these guys were in absolute peak physical condition and did a lot of dives to discover their air limits.

120m is a long, long way - are you sure of this?

 

[espenskogen]

120m is a long, long way - are you sure of this?

Well, as sure as you can be, without having been there whilst it happened..

The guy I had in mind here told me he'd done that depth in the red sea whilst working as an instructor there.. Having said that - I guess he could simply have been so narked he had no idea how deep he was, so I guess the prudent answer would be : No, not entirely - The guy said he did - But he could have been lying/wrong etc.

BTW: Mark Andrews broke 156 meters on Air in 1999.