PADI's dive depth standards - Vague?

[jbd]

Nope...It is the "suggested" maximum depth. The premise is based on a diver at 132 feet is under a ppO2 of 1.4 ata O2. At this depth it isn't "impossible" to suffer an ox tox hit. It isn't likely but based on Dalton's Law you are breathing the equivalent of 100% O2 at the surface. Is it likely you will suffer an ox tox hit at 132'...no...but again, it isn't impossible and that's why PADI "suggests" 130. Above 132' you can't suffer an ox tox hit on air. Many divers have pushed it to 1.6...218'...and beyond and not suffered an oxygen toxicity hit...but theses guys are not recreational divers either.

It is a suggested maximum depth for no stop required diving. The rest about oxygen toxicity is not correct. Breathing air at a depth of 132 FSW is close to breathing 100% O2 at the surface which is not the same as breathing air at partial pressure of 1.4 atm which occurs at a depth close to 190 feet. A depth of 198 fsw will give an O2 partial pressure of 1.47 atm when breathing air.

Oxygen toxicity is not dependent upon ones status as a recreational diver or a technical diver. The physiology is still the same.

From re-reading your post I get the impression you are thinking of nitrox but using that info in reference to air.

 

[GA Under Water]

No, I don't taking Discover Scuba over and over is better. I think your friend should go ahead and take the full course and get certified as he/she seems to enjoy diving.

If one makes it through 2/3's of the OW course then they should finish the other 1/3 IMO. In and of itself I don't see the 2/3's as being acceptable. Referring back to the post by cgvmer, circumstances prevented them from finishing thier initial course as planned but the instructors were able to use PADI's Scuba Diver program to prevent them from potentially having to start all over again.

You and I agree on this. I have already expressed that to my friend. He is supposed to be getting certified this summer.

 

[rawls]

It is a suggested maximum depth for no stop required diving. The rest about oxygen toxicity is not correct. Breathing air at a depth of 132 FSW is close to breathing 100% O2 at the surface which is not the same as breathing air at partial pressure of 1.4 atm which occurs at a depth close to 190 feet. A depth of 198 fsw will give an O2 partial pressure of 1.47 atm when breathing air.

Oxygen toxicity is not dependent upon ones status as a recreational diver or a technical diver. The physiology is still the same.

From re-reading your post I get the impression you are thinking of nitrox but using that info in reference to air.

jbd...you are absolutely right. It's late My mind was definitely mixing those things up...1.0 at 132'. The physiology is definitely the same. Pressure is pressure. I was "trying" to say, albeit poorly worded, in reference to technical diving, that some have pushed the limits beyond 1.6 and not suffered an O2 hit, but the risk is increased the deeper the dives. I can see, however that I definitely worded it wrong by saying "but these guys are not recreational divers either." Without a doubt it does sound like I was separating the two. Thank you for the correction and clarification.

 

[Belmont]

I had enough time for Scuba Diver last year in april.
Last Xmas I finished my OW.
This fall I'll go for AOW and, from then on, I plan on improving my skills and enjoying
diving.
I think having the possibility of splitting the course in sections makes it interesting.
I paid 200$ US for Scuba Diver and 200$ US for OW.
I dove 12 times in 7 days at depths between 35 and 60 feet and once on a plane wreck at 75 feet.
Dives averaging 30 to 35 minutes.
All this in Jamaica at an all inclusive resort. (Sandals)

I think Padi is a business therefore they are in it to make money and that's fine with me.
I am old enough to be able to evaluate the seriousness of an organisation and I think PADI is serious and the instructors who taught me were serious and safety oriented.


On my last trip I brought my three children aged 18, 20 and 22 and had them introduced to Scuba diving.

Seeing them going over a coral patch at 35 feet brought tears to my eyes, I nearly had to clear my mask...

My son also did his OW, we studied together, and he is going to be my dive buddy from now on.

Can't wait to dive again.

 

[mobster75]

With regards to the "limits" imposed by PADI:

They don't sound vague to me. PADI is covering their butts with risk management and I assume have developed those depth recommendations based on the simple thought "How far down would the average diver with this training be able to get themselves out of some basic predicament?" and temper it with the experience blurb. We are all individuals and 60 fsw to some is easier compared to 30 fsw for others. If you aren't comfortable at any depth then don't go down there. If you just have OW and you want to go to 150 fsw on your 5th dive because you feel "No problem. Whats the issue?" then good luck!


With regards to the PADI Scuba Diver issue:

I feel Scuba Diver is a semi glorified Discover Scuba diver, but it has its places as others have mentioned... I became SD certified before I was OW certified because I had issues w/ the full mask removal/replacement/clearing. I stayed SD certified for 3 years until I could move past the issue and cleared OW with flying colors. Otherwise I might have dropped scuba diving in general.


Overall, I think that machoism and bad attitude contribute to most diving problems. If you think you're invincible then you're in the wrong sport/hobby. Mother Nature has no pity for an unprepared/unexperienced diver. A couple times I've been nervous on dives and I've not gone past that point even though I was the only one to bail. Didn't care if I looked like a wimp... I got to go home to my fiance and family and dive another day.

Isn't that what it's all about?

 

[String]

As well as the depth recommendations theres also the "dive within training and experience" part of the qualification. Therefore if you dived to 18m as part of training, suddenly diving to 40m would be outside that.

Not being a legal authority agencies CANT legally impose depth limits on divers, they can simply give recommendations. If someone qualifies to 18m under their course they cant legally stop them going deeper but can strongly recommend they dont without further training. Its not just PADI with this.

Its up to dive centres and common sense to enforce these recommendations.

I dont see the recommendations as vague in the slightest - you are trained to dive to a specific depth in the course and then after it to dive in conditions similar or better than you trained in. 18m on a coral reef doesn't qualify you to 40m on a wreck.

The one thing that does annoy me is the "130ft max recreational depth". I'm not sure which lunatic group dreamed up this artificial definition at all.

As for PADI Scuba Diver - yet to see a single person ask to do this "qualification" - it is effectively just a deeper discover scuba and qualifies you to do absolutely nothing outside that. The only ones we awarded last year were to divers who for some reason or another were unable to grasp some of the concepts of basic open water. Quite often children who had been enrolled on the full OW course but couldnt get the hang of tables etc. Or one person that failed entirely to complete 2 OW skills. Scuba diver was given to them so they got something instead of nothing. Its not something i think someone should aim at the start to get!

 

[Steve R]

The one thing that does annoy me is the "130ft max recreational depth". I'm not sure which lunatic group dreamed up this artificial definition at all.

So what would you propose, and why?

 

[String]

Why have one? Theres no clear defined line between recreational and technical.

You arent perfectly safe at 129ft on a single tank but suddenly need a twinset and deco training to get to 131ft.

Its a daft limit devised by someone in an office who doesn't actually dive.

Just stick a depth limit on qualifications and be done with it.
Thats how it works here with most UK based agencies. Theres no cutoff depth where it ceases to become recreational. You just dive to your certification and if you want deeper, work towards another one.

 

[J.R.]

Why have one? Theres no clear defined line between recreational and technical.

You arent perfectly safe at 129ft on a single tank but suddenly need a twinset and deco training to get to 131ft.

Its a daft limit devised by someone in an office who doesn't actually dive.

Well:

1: One could argue that all 'definitional boundaries' are artificial... or one could argue that developing boundaries such as 'recreational' and 'technical' are good for establishing 'guidelines' for dive training and the practice of diving from admistrative and practical apsects. One could also look at the PPO2 at 130 feet and the 'recommended guidelines' and realize that, given that everybody's physiology is different ... 130 is a good point where ya' might want to start looking at diving in a different way than ya' might want to dive at 30 feet.

2: Aint' no such thing as 'perfectly safe' anywhere bubba'... if ya' think so... go back to class and re-do diving 101...

3: "Its a daft limit devised by someone in an office who doesn't actually dive." ... well, this sounds about as 'reasonable' as saying that the above was written by somebody who's feeling a bit inadaquete these days and who's Viagra isn't helping. Neither statement, I'm sure, is correct... but either could be HIGHLY incendiary...

 

[HowardE]

Its a daft limit devised by someone in an office who doesn't actually dive.

Do you really think that??