What is the PADI "deep" specialty?

[miketsp]

..snip..
much less diving to 40 meters with a tiny 12 liters...

I have +10 years of diving experience and I would never go to 40 meters with the equipment you described.

DareDevil

There are lots of dives in the 40m range, all around the world, being done every week by many rec divers on air, on single AL80s.

 

[bwerb]

There are lots of dives in the 40m range, all around the world, being done every week by many rec divers on air, on single AL80s.

What's your point? I have an uncle who likes to shoot bottlerockets out of his straw cowboy hat. Just because some idiot does it doesn't make it something we should line up to do.

 

[MXGratefulDiver]

There are lots of dives in the 40m range, all around the world, being done every week by many rec divers on air, on single AL80s.

People take unnecessary risks for many reasons ... rarely good ones.

They cannot be justified by saying "lots of people do it" ... think about how many people , all around the world, drive themselves home from the bars every night after a few too many drinks. Just because the majority of them manage to make it home in one piece doesn't make it any less risky.

Diving deep on air ... especially on a relatively small cylinder ... entails risks that can be managed, but are better avoided - narcosis, exceeding NDL, and OOA being the three most common ones.

Granted, all of these risks can be minimized with proper planning and execution ... but ask yourself (and be honest) how many of the people who do these kind of dives put the effort into their dive planning to rely on more than simple luck to get back safely?

How many have the sense to recognize the effects of narcosis in themselves, and head up shallower when the effects become obvious ... and potentially dangerous?

How many have the knowledge to do anything other than rely on a computer to tell them when they're running out of no-deco time?

How many of them even know how to do the calculations to determine if they're even carrying enough air to do the dive they're planning?

Not many ... and for the majority, the only thing that keeps them out of trouble is that during those dives they don't have to deal with anything out of the ordinary. Those who do, sometimes, don't live to learn from the experience.

... Bob (Grateful Diver)

 

[Jason B]

I have +10 years of diving experience and I would never go to 40 meters with the equipment you described.

DareDevil

not much of a DareDevil are you (sorry, couldn't resist)

jason

 

[miketsp]

People take unnecessary risks for many reasons ... rarely good ones.

They cannot be justified by saying "lots of people do it" ... think about how many people , all around the world, drive themselves home from the bars every night after a few too many drinks. Just because the majority of them manage to make it home in one piece doesn't make it any less risky.

Diving deep on air ... especially on a relatively small cylinder ... entails risks that can be managed, but are better avoided - narcosis, exceeding NDL, and OOA being the three most common ones.

Granted, all of these risks can be minimized with proper planning and execution ... but ask yourself (and be honest) how many of the people who do these kind of dives put the effort into their dive planning to rely on more than simple luck to get back safely?

How many have the sense to recognize the effects of narcosis in themselves, and head up shallower when the effects become obvious ... and potentially dangerous?

How many have the knowledge to do anything other than rely on a computer to tell them when they're running out of no-deco time?

How many of them even know how to do the calculations to determine if they're even carrying enough air to do the dive they're planning?

Not many ... and for the majority, the only thing that keeps them out of trouble is that during those dives they don't have to deal with anything out of the ordinary. Those who do, sometimes, don't live to learn from the experience.

... Bob (Grateful Diver)

Depends what you call the wrong reasons - go back just a few years and in many places mixed gas diving was unavailable outside North America & Europe and there were a lot of interesting things to see below 40m.

I just happen to know a lot of divers that do a lot of deep diving.
Among those I class as advanced I would say over 90% have done the V17 Corvette at Fernando de Noronha, on air, that's 55m to the cabin and 60m to the sand.
If they were not capable of planning and executing to a plan and handling the occasional incident then there would be a certain casualty rate - I never heard of any in the many years that people have been diving this wreck.

Over a long period statistics don't respect luck - only preparation.

 

[DareDevil]

not much of a DareDevil are you (sorry, couldn't resist)

jason

Spot on Jason ;-)

When you have seen people dying and your have a family and kids you start to see things in a different way.

DareDevil (aka Paolo)

 

[DareDevil]

Depends what you call the wrong reasons - go back just a few years and in many places mixed gas diving was unavailable outside North America & Europe and there were a lot of interesting things to see below 40m.

I just happen to know a lot of divers that do a lot of deep diving.
Among those I class as advanced I would say over 90% have done the V17 Corvette at Fernando de Noronha, on air, that's 55m to the cabin and 60m to the sand.
If they were not capable of planning and executing to a plan and handling the occasional incident then there would be a certain casualty rate - I never heard of any in the many years that people have been diving this wreck.

Over a long period statistics don't respect luck - only preparation.

What I believe that other people are trying to say is that the oceans are full of wonderful spots to see, even well below 40 meters which is, after all, not so deep: the point is only "how" you want to go there.

At 40 meters you are likely to end up in a deco dive and you already venting (in ideal conditions) 100 liters per minute of air from a bottle (12 liters) that can give you less than 18 minutes of air at that depth before reaching the reserve and without a computer that can help you to plan a better deco profile.

Call me stupid but I would like to have a better safety margin: I would like a diving computer, a bigger tank (15 or even 18 liters: you may need to support your buddy with that air, don't you?) and back-up equipment.

I met people that like to explore deep caves and they routinely dive to 80-90 meters: most of the diving computer available on the market stop working around 75-80 meters so you can imagine which kind of equipment and techniques they use (exotic mixs, special deco procedures and so on).

DareDevil

 

[tonyjk]

I just recieved my AOW, I was on a liveaboard off the coast of California. My SCUBA instructor had chartered the boat. One of the specialties was deep (along with Nitrox, Navigation, and night-limited visibility). Of my 8 dives, 5 of them were 74 feet or more. I had one at 91 feet and another at 113 feet. However I dove conservatively, most divers on my 91 foot easily hit 100. On my 113 foot dive most were 125 or more. I was told that the "recommended" maximum depth is 100 feet with my certification. However I was also told that the absolute maximum is 130 feet and that this figure was based on Doppler ultrasound research.
Basically, you should try to stick to 100 feet. Bare in mind that you are breathing 5 times your Surface Rate Consumption at 132 feet and are increasing your chances of DCS dramatically.

 

[miketsp]

..snip..
At 40 meters you are likely to end up in a deco dive and you already venting (in ideal conditions) 100 liters per minute of air from a bottle (12 liters) that can give you less than 18 minutes of air at that depth before reaching the reserve and without a computer that can help you to plan a better deco profile.
..snip..

You are certainly going to end up in a deco dive. The US taboo on recreational deco dives is not shared in many other countries.

100 liters/min - in ideal conditions?? That corresponds to a SAC of 20l/min at the surface. I doubt if I consumed that much air during my basic OW course. Both my wife and I have SACs below 12l/min.

I don't do 40m+ dives by the computer, the case I quoted of the V17 at Noronha is normally done on CMAS tables. The computer is just an additional control device.

..snip..

Call me stupid but I would like to have a better safety margin: I would like a diving computer, a bigger tank (15 or even 18 liters: you may need to support your buddy with that air, don't you?) and back-up equipment.

Nobody is calling you stupid, just conservative, that's not a bad thing. Always dive within your comfort level. Stress leads to other problems.

When I dive beyond 30m I carry a table which lets me easily review rock bottom to get both of us back on one cylinder.

..snip..
I met people that like to explore deep caves and they routinely dive to 80-90 meters: most of the diving computer available on the market stop working around 75-80 meters so you can imagine which kind of equipment and techniques they use (exotic mixs, special deco procedures and so on).
DareDevil

Nowadays I don't know anybody that dives air regularly beyond 60m, although back in the early 70s I worked with commercial dive teams that routinely went to 85m+ on air, the tables were much more aggressive and we didn't send that many people to the chamber.

 

[chrisch]

I just recieved my AOW, I was on a liveaboard off the coast of California. My SCUBA instructor had chartered the boat. One of the specialties was deep (along with Nitrox, Navigation, and night-limited visibility). Of my 8 dives, 5 of them were 74 feet or more. I had one at 91 feet and another at 113 feet. However I dove conservatively, most divers on my 91 foot easily hit 100. On my 113 foot dive most were 125 or more. I was told that the "recommended" maximum depth is 100 feet with my certification. However I was also told that the absolute maximum is 130 feet and that this figure was based on Doppler ultrasound research.
Basically, you should try to stick to 100 feet. Bare in mind that you are breathing 5 times your Surface Rate Consumption at 132 feet and are increasing your chances of DCS dramatically.

I think you should ask the instructor for your money back....

Re Padi, I thought things had changed and 100' was the limit? Your post suggests not. I don't know I haven't done anything with Padi for years. Most agencies same 100' recommended 130' absoloute.

Re Padi deep, only worthwhile if you are fairly new diver, Otherwise go for one of the technical agencies for deep qualifications. You get to learn skills like shooting a bag and so on.

Chris