Diving beyond cert?

[tursiops]

So you like it better than the appearance of my blog?

I have stated repeatedly that this is not meant to be absorbed. It is way too much. It is simply a guide to work through to create a dive plan and build confidence.

But ultimately, it is know your gas consumption rate, your swim rate, and create a route to follow based on a map, which expected cylinder pressure at various points.

"Leave the bottom at 700 psi" is stupid. Is 700 psi sufficient min gas for all depths? Not at all. If you oversimplify it because you think students are dumb, you just get them into trouble. I haven't had an issue with students getting basic concepts that unfortunately are missing from most open water courses. There are some amazing instructors who do far more than me and don't overwhelm their students. I have a few open invitations to observe their classes which I will do when I am in their area.

I was not asking you to over simplify, just to simplify. I guess you don't have anything to offer.

 

[inquis]

One simple rule of thumb when diving a single AL80 is to leave the bottom at:

GasPressure_psi = 10*(Depth_ft+30)
GasPressure_bar = 3*Depth_m

These are easy to compute approximations to more rigorous calculations. (FWIW, they do not exactly agree with each other, but are pretty close at 100 ft/30 m.) They are, however, fairly conservative, and even moreso if you round depth up for easier computation (e.g., at 86 ft, use 90 ft and leave at 1200 psi).

That said, I would encourage everyone to learn to compute things on your own, as there are some parameters you may find overly conservative as you gain experience. (For example, I personally feel 10*Depth_ft to be sufficient for myself and an instabuddy.) It's also possible the above is insufficient for your needs.

Regardless, I'd say the above is more useful to OW divers than "be back with 500 psi".

(This allows for a total RMV of 2 cuft/min, 1 min at depth, and a safety stop. While simple, it is about 100 psi short of a more rigorous calculation at 130 ft. Alternatively, it agrees with a 1.9 cuft/min RMV at 130 ft. The metric version will be about 6 bar short at 15 m.)

 

[Dapper Dan]

You'll probably find, if you're going on any sort of charter from a reputable shop, they'll have their own rules. Here for dives beyond 60' it's "Must be AOW or better, must have 3 or more boat dives, must have computer, must have SMB, must have dived in the last year. " YMMV

If it's your own boat or your buddies boat, you're on your own pretty much in America. There's things you ought to know to safely dive deeper like gas consumption, narcosis, etc. My bottom time on the U-352 at 116 feet is 18 minutes. My bottom time on the Theo Parker at 60 ft is 60-70 minutes. I always get back on the boat with at least 30 PSI

If you aren't going to take the PADI AOW class at least buy the PADI AOW book and read and understand it.

 

[LI-er]

Straight from PADI's website FAQ.

Yes, with proper training and certification the max depth is 130'. Which your response confirms, as per the PADI FAQ that you provided a link to and I copied below. However the post I was responding to said the Op is certified to 130' and that is not correct.

You would not be diving beyond your certification; that is to 130 ft.

"With the necessary training and experience, the limit for recreational scuba diving is 40 metres/130 feet. Beginning scuba divers stay shallower than about 18 metres/60 feet. Although these are the limits, some of the most popular diving is shallower than 12 metres/40 feet, where the water’s warmer and the colors are brighter."

The PADI website clearly states that the limit for OW divers- which is the certification level of the Op, is 60 feet. Bold and italics are added by me.

interesting that it says you "should" take aow to dive beyond 60 feet. not that you have to.

That's because there's no scuba police down there. However most commercial charters and even some life insurance companies (that might refuse to pay following a dive accident where the diver exceeded his or her certification limits) will follow certification limits even if they're difficult to enforce.

You shouldn't drive 100 mph in a 60 mph zone on a deserted country road even though there's no cops there to ticket you.

This post -- along with most of the others in this thread and on ScubaBoard in general -- does not understand that the OW cert is to 130 feet. It confuses a certification depth with a recommended maximum depth that depends on your training and experience.

Please stop "muddying the waters" and giving potentially dangerous and false facts, by suggesting that all scuba divers are certified to 130' at the completion of their 4th successful open water checkout dive. Just because they "can" dive to 130' doesn't mean they 'should' dive beyond their level of training and certification, it violates PADI standards (and that of other scuba certifying agencies and will not be permitted by most commercial charters.

SSI makes a more definitive statement, omitting the word "should" that has @tursiops confused.

The SSI Open Water Diver is our most popular certification level. This globally-recognized certification will allow you to dive with another certified diver, worldwide, to depths of up to 18m / 60 feet

This is much like getting a driver's license in a small, rural town means you can drive in big city, rush hour traffic if you want to.

No it's much like getting a driver's license for a car and hopping into a tractor trailer and taking it for a spin down the highway.

 

[happy-diver]

Well I have no overblown paragraphs, that would make it appear that I was giving responsible advice
complying with what my fellow scubaboardians think is expected in the basic forum, just some words

I got OW certified (PADI) in May and have only been on a few dives since. I'd like to go diving again soon, but where I've been invited is generally 60-100' where all the interesting stuff is. I seem pretty comfortable, and am not terribly worried about the depth. I am signed up for AOW next month already. I'm wondering if there's any critical reason I shouldn't do these dives? Dive buddy is really experienced and reassuring, and I'm not above aborting at the first sign of problems or me being uncomfortable. Thoughts please?

Just do it, or never learn, and realise if you do not push past where you are, that is where you will stay

 

[34109411]

The most important thing is knowing you have sufficient gas for you and your buddy to ascend to the surface in the case that one of you suffers catastrophic gas loss and you have to share gas to the surface.

I wrote a dive planning doc for my area:
(),
but the concepts are universal. If you know the site, have a map, go through the process and see how comfortable you are once going through this excessive exercise. The point of the document isn't memorization, but to develop a plan for new places and being comofortable throughout the dive as you monitor your gas consumption and compare to expected cylinder pressures at different points of the dive and always abiding by min gas.

wow i am amaze by your document ! it seem you have access to 1000 dives sites compare to me, lucky you are.

 

[Blackcrusader]

This post -- along with most of the others in this thread and on ScubaBoard in general -- does not understand that the OW cert is to 130 feet. It confuses a certification depth with a recommended maximum depth that depends on your training and experience.

When I mention this I get told off lol You get more experience by diving with more experienced divers.

 

[arew+4]

When I mention this I get told off lol You get more experience by diving with more experienced divers.

The major difference between a 60' no deco open water dive, and a 100' no deco open water dive, is 40'. All else being equal, vis, temp, current, etc, the additional/elevated/aggravated risk factors are the potential for narcosis, the accelerated gas consumption, and the abbreviated NDL. As long as the OP, is aware of these risks, is mentally and physically fit, has a reasonable dive plan, an experienced buddy and clear communication protocols, he should be fine. Is it ideal to go to 100' on your tenth dive? Probably not. Is it prohibitively dangerous? No.

 

[submergenarcosis]

If your buddy is experienced then go for it. At 100’ you can’t stay that long so you need to monitor NDL constantly.
Air consumption may also be something to keep an eye on. Follow your computer.

 

[MB NZ]

I'm the opposite of the SCUBA Police, I don't know what that's called, but hopefully someone will come up with a cool name. I had a lot of first time diving experiences without training, but less than 10 dives, you are a baby in diving terms, take it easy! Sorry to be a blunt spoilsport.