Advanced open water?

Does anyone have their advanced open water? :smt102

I've been looking at nitrox classes, and EVERYONE tries to get me to sign up for aow and nitrox at the same time. It's like $80 extra, and I can't fathom why I would ever need this class.

I'm doing intro to cave this summer, and hopefully rescue diver (I've heard good things about this course), and was thinking the money would be better spent towards those two classes, does anyone agree?

I'm willing to take it if I'll gain something from it, but if they're just going to take me to 80ft deep and say "congrads! here's your card!", I'll keep my money, and take AOW when I want to do one of Lloyds west palm trips that includes it.

I can't imagine anyone doing cavern without advanced and nitrox first....let alone intro to cave. You best recheck your plans and maybe think about slowing down...take advanced and nitrox. then rescue. then maybe cavern summer of 09 after a bit of experience with open water nitrox adding more advanced dives than you've been doing, before attemtping cavern/intro to cave. no hurry, the caves will always be there.

-skip

I agree with Skip. You cant replace experience with a C-card. Get the advanced, then hit nitrox and spend the summer diving.

Quote:

---

Originally Posted by skip

I can't imagine anyone doing cavern without advanced and nitrox first....let alone intro to cave. You best recheck your plans and maybe think about slowing down...take advanced and nitrox. then rescue. then maybe cavern summer of 09 after a bit of experience with open water nitrox adding more advanced dives than you've been doing, before attemtping cavern/intro to cave. no hurry, the caves will always be there.

-skip

---

What exactly do you learn in advanced open water? Normally when I see a full cave diver around these parts, I think to myself "that's who you model your diving style after", yet when I see advanced open water, I think "who the hell doesn't know better than to drag their gauges and kick up silt?" I'm open to taking that class, but before spending money on it, I just want to know what I get for it. So far the default answer seems to be "It's a credit towards your dive master certification".

I'm not opposed to the idea of taking it, but I'd like to know what I gain, so I can spend the (limited) financial resources I have in the best way possible.

AOW can be good and at the absolute least you will get some dives in under the scrutiny of an instructor's eye. The class consists of 5 "speciality" dives. In it's current form I view it more as a marketing tool for PADI to get more people to buy full specialty classes or to go for the "Master Scuba Diver Challenge". BUT, there are some of the specialties that compliment OW training nicely. In my opinion, they are Deep, Night, and Nav (all required I believe), Peak Performance Bouyancy (elective but absolutely great w/ the right instructor). Wreck would also be a decent one because you will start to use a reel (earlier the better). Again, only 5 dives but you can take something away from it. More importantly it is required if you want to be a Rescue diver which should be required before any overhead training IMO. BTW way I am assuming this is PADI since it's an $80 add-on to Nitrox. Some other agencies, such as SSI and YMCA, have a more robust advanced course that is more deserving of the name.

Quote:

---

Originally Posted by jj1987

so I can spend the (limited) financial resources I have in the best way possible.

---

Then forget about cave for now and do your nitrox/AOW and dive for a few years. Perhaps a cavern class down the road. (didn't you post on TDS that you took that?). Tech or Cave diving is serious money commitment (many many thousands...).

Before you hit the cave/tech classes, you should have a slow constant progressions in OW to build experience. That means getting your AOW/nitrox and doing dives at that level.

It doesn't mean that you have to suck in OW. Good technique can be gained with an early tech/cave class like fundies, cavern or intro-to-tech. That would be the smart class to take later this year after your AOW/nitrox.

I personally think one should gain a few years of experience diving OW stuff before doing any cave/tech class other than the early ones I named. A lot of brand new diver wrongly think that just because they passed a fundies/cavern/etc course they are ready for real cave/tech classes... Being able to hold trim is nothing compared to real experience.

While one can be a fairly good diver from scratch, experience is only acquired by diving.

I could have swore that AOW was a requirement before even taking cavern....

It sounds as if you have taken cavern already, true?

Well technically,

If you look at standards, OW allows you to dive to 60' following NDL tables. AOW limits your depth to 130', again following NDL's. The benefit of diving Nitrox has been established in numerous posts, so I won't get into it here.

Yes, you can dive deeper without a AOW card, nobody will stop you. But you will see that in Cave diving, there are certain limits placed upon the diver based on their training levels. If you are willing to violate depths at the OW / AOW level, then maybe you should think twice about overhead diving.

This is not a slam on you or your abilities.

AOW is not a requirement for all cavern classes, just some. It is also a requirement for some Rescue courses.

I will agree with you jj, not all AOW courses are worth the card you get at the end of the course. But don't discount all of them because of the way a majority of them are. Some instructors will actually give you value in your course. For instance, I teach my AOW students about buoyancy and trim, proper gas management and dive planning, and proper buddy awareness and communication (not like most OW courses provide). But then again, I'm also a cave diver. ;)

wow, pump the brakes here player. your first question might be better phrased "do any cave divers out there NOT have their AOW" anyone...

no disrespect. go for it, take lots of classes, but take enough time to digest the material in real-world situations before moving on to the next level. take your time. most importantly, have fun and dont bite off more than you can chew and get yourself killed. its unfortunately not that hard to do, but i hope you already know that. BTW, I was one of steves students. I got my first OW in '86, intro in '01 and my app in '07 full will be '08... just for your reference.


--jm

Quote:

---

Originally Posted by battles2a5

The class consists of 5 "speciality" dives.

---

I think I did the navigation specialty and deep diving for my advanced few years back, both were valuable before venturing into the overhead environment.

I agree. I don't know if it was my instructor or just one of those "Ah-ha!" moments, but the peak performance bouyancy dive really made it all click. It really changed the way I dive. Not because of the actual class, but it helped my understand the fundamentals and variables associated w/ bouyancy. So again, it's all about what you take from it. I think everyone has given some good advice on this thread.

Without AOW you could be in the interesting position of not being able to go deeper then 60' in the open water but 130' in the cave. We use to laugh about that one a lot because Kathleen still had her junior OW card - and Full Cave.

So we could only dive caves where the entrance was shallower then 60'. ;)

The joke ends at Trimix because it's an OW cert also.

Seriously when you go to the Keys most dive shops have no idea what a cave card is and they frequently want to see some OW certification regardless of what cave level you are certified.

Some Nitrox certs pre-req AOW so are just as good as AOW - other don't so there is no guarantee. If the shop isn't sure you might just get stuck having to pay a divemaster to follow you for the dive. :(

Quote:

---

Originally Posted by jj1987

Does anyone have their advanced open water? :smt102

I've been looking at nitrox classes, and EVERYONE tries to get me to sign up for aow and nitrox at the same time. It's like $80 extra, and I can't fathom why I would ever need this class.

I'm doing intro to cave this summer, and hopefully rescue diver (I've heard good things about this course), and was thinking the money would be better spent towards those two classes, does anyone agree?

I'm willing to take it if I'll gain something from it, but if they're just going to take me to 80ft deep and say "congrads! here's your card!", I'll keep my money, and take AOW when I want to do one of Lloyds west palm trips that includes it.

---

you will gain alot, believe me it's part of the fundamental knowledge base, and in fact $80 is cheap, I charge $100 for that add on. Your biggest advantages will be in the 60-90ft range so it will help with exactly what you are going to be doing.

have fun in WPB

LL

When I tought AOW in Michigan my students, at Gilboa Quarry, were given the basics of line and reel work, advanced navigation in zero vis, how to deploy a lift bag for ascent without an up-line or anchor line, and then we spent a day out on Lake Huron doing two mid-range wreck dives (exterior only). When I came down here for my Cavern and Intro course it was recommended to me to have at least 100 OW dives in varring places, not just the carribean. I was also a NAUI Instructor. I learned more in those 4 days than I did 30 years of diving in the Great Lakes. I would advise taking the Cavern and Intro course. If you never set fin in a cave again, you will be a better diver for it. I have been told that the novice cave diver with 20-30 dives, has more watermanship skills than most OW course directors. Food for thought...Ken

I have been diving for a little while now, & just bought a new dry suit. I so badly would love to take it to Manatee or Eagles Nest this weekend. Heck ¾ of the people I dive with have em’ I understand how it works. “It will be fine” But I know the right thing to do is take the class. So I guess this week I’ll find my self in the pool <lol. So all I have to do is convince the instructor we need to have the pool cover on and take the class at night. In order not to bruse my full cave ego.
So here is my take on some of those classes:

An opportunity to dive with an instructor, with an open mind to learn something.

If that don’t work how about it will improve your awareness, a lesson best not self taught.

Do some agencies require AOW before you can take intro or cavern? Or is it just a certain number of dives?

Quote:

---

Originally Posted by tflaris

Do some agencies require AOW before you can take intro or cavern? Or is it just a certain number of dives?

---

NAUI requires it.

I do not have my AOW card.

However I did not have your average OW class, mine lasted 6 weeks and included rescue etc. (not rescue to the extend of the C class rescue).

I went from OW, to Nitrox, started Adv OW and decided I wasn't going to spend my money on it, to me at that point in my diving career there was no "value add" to taking the class so I did not.

You need to evaluate the class for yourself and determine does this class give me a value add or not, do not look at it from the perspective of do I need this card before I can proceed to the next card.

If the goal is to hop from card to card until you get the collection you need to take cavern/intro in my opinion is not the way to do it, look for skills to add and add from hop to hop so that when you get to cavern/intro your best equiped for the challenges, this may or may not include AOW for you.

Drill the instructor, if its one of those AOW classes where they take you in the dark and swim you in a circle, then bounce you to 60 feet for your "deep" dive etc, then its paying for a card, no value add. If they take you out, beat you up, drag you down to 130 or whatever it is now and these are areas you have not done before, then there could be some value add.

I'd be plenty willing to pay for certain scuba classes that give me no certifications, I just haven't found those yet.

I guess my opinion is well within the minority here...

If you have good OW buddies with good bouyancy, trim, experience, or cave diver friends who'll dive with you in OW water conditions - just mentor under them.

Rescue and Nitrox are the only recreational courses I've found worthwhile. My OW instructor did teach me bouyancy, weighting, and trim - I guess that makes a huge difference. Through my OW "career" so far, I spent the majority beach diving passes and shore divable wrecks through limited visibility, surf, and currents - quite often at night while spearfishing. Once I ended up taking those courses, they were far too basic to gain anything from them. The experience was far more rewarding and helpfull.

Do you need an AOW card? Plan to dive the Oriskany? Speigal Grove? Need it for further coursework? If not, I wouldn't bother.

SSI certifies OW divers to 130' with a recommendation that divers stay above 100'. Atleast thats what was taught in 2003 and I just browsed through my old OW course book(funny stuff) without anything stating a 60' recommendation or cut-off depth.

All that being said, if you don't have the opportunity to get the experience safely in place of the card, perhaps its worthwhile...

Don't think I'd rush into any overhead course without experience in various basic conditions, that will be covered in AOW(briefly). So at the very least pick up the AOW course before signing up for anything more significant.

Ya know, it's all about the instructor.

If you can find an instructor with a cave cert (not necessarily at instructor level), then do it with them. Tell them of your intention. They will use the AOW dives to help you develop useful skills for cave. Deep, navigation, nitrox, search and recovery amongst others - you could make this a really nice pre-cave primer. if they're cave or wreck certified, they'll help critique your finning technique at the same time. it's not in the syllabus, but an instructor with the right background will help you do this.

But use the average OW instructor, and I'll agree that you won't learn as much. Something, but not as much.

So.. do your homework, find the right instructor, and you'll learn plenty... AND have a useful cert for when you want to do a wreck or a deep dive off a boat, and they want to see the AOW cert. That IMHO would be the most useful way to spend your money

I think you have to have your AOW card for a padi cavern course,I did but it may have changed.

Quote:

---

Originally Posted by fixxervi6

I'd be plenty willing to pay for certain scuba classes that give me no certifications, I just haven't found those yet.

---

I hold a 3 day 6 dive buoyancy class (Not PADI PPB). It includes proper finning techniques, non silting techniques, properly weighting of the diver, no vis stops, non silting night navigation 2' or less from the bottom, helicopter kicks, proper doubles isolation procedures etc...

This class has no C card. It just teaches you to dive well. It's not designed for card collectors.

just my .02psi

Quote:

---

Originally Posted by defunct

I could have swore that AOW was a requirement before even taking cavern....

It sounds as if you have taken cavern already, true?

---

yeah, I took my OW early summer of 1999, and received the NAUI card on my 12th bday (12/13/99). Almost 1 year later (and about 100 dives later as suggested by my instructor) I took my cavern (4/8/00). I've slowed that pace down (we were diving 3-4 times a weekend, and then it went to 2 dives every other weekend), but now that I (FINALLY!) have a job that doesn't require weekends, it's time to get back at it.

I think what I'll do is take AOW from a cert cave diver......I'll have to find my snorkel.....that thing hasn't been out of the box in about 3 years lol.

If you do take AOW, you'll almost certainly find that your experience is far beyond the level of your classmates. In fact, you have more dives than some instructors I know. My experience with PADI AOW class was that it was a complete waste of time. My experience level and skills far exceeded what was asked of me. This may have been because I took it as part of a package deal at a resort dive center. However, my PADI rescue class (different instructor/dive center) was excellent. I took a NAUI nitrox class (another different instructor/dive center) that also exceeded my expectations.

IMHO, if your instructors aren't requiring it, you could get by without AOW. However, to reiterate what everyone else is saying, if you have a great instructor to train with, then it is time and money well spent no matter what course you are taking.

Some interesting clips from my nitrox course. I'll leave these pics without captions, they speak for themselves.

http://jamesg.net/misc_stuff/message...i/bouyancy.png
http://jamesg.net/misc_stuff/message...s_dangling.png

Take the nitrox class and spend the 80$ on gasoline and nitrox and go cavern diving.

Quote:

---

Originally Posted by Daedalus

Take the nitrox class and spend the 80$ on gasoline and nitrox and go cavern diving.

---

$80 on gas will only get you from Ocala to southern Gainsville these days :yawinkle:

Quote:

---

Originally Posted by Mike Edmonston

$80 on gas will only get you from Ocala to southern Gainsville these days :yawinkle:

---

Depends--did you buy gas in Ocala ($3.16) or Gainesville ($3.32-.45)? :D Fortunately, I filled up on my way to Gainesville in Ocala. Unfortunately, two days of diving here left my truck needing more gas, and I won't be back in Ocala too soon....paying $.20 more per gallon.....thank you very very much Alachua County Commissioners. I hope your little cars break down and the rental place loans you Hummers!! ;)

I'm with whoever said that Nitrox and Rescue were the worthwhile classes. My AOW class was really five dives with an instructor watching me, and not worth much more than that.

It is instructor dependent, though. The man who mentored me as a new diver teaches a fantastic AOW class, that challenges even fairly advanced divers. But it's unusual.

I'd say a class like the one Mike describes, or what I took, which was GUE Fundamentals, is a much better investment than AOW.

Im sorry,I thought you still havent gotten a cavern card.If so,I wouldnt bother with the AOW class unless you feel you need more skills in the ocean.Nice pictures of the consoles scraping the bottom.The last offshore dive I did some kid on the boat sitting beside me was holding his footlong console and sort of scoffing at my single diverite spg.

I found cavern class to be the single best class I have ever taken. Even more then cave classes, because cavern took me from a relatively (ok, totally) clueless OW diver to someone who started to get the idea that there was a better way to dive.

I found my original OW certification class to be worthwhile, since it taught me what a regulator was and how not to kill myself as I surfaced.

I found rescue class to be useful in techniques of helping other divers (Actually happened once)

I did not find AOW particularly useful, though I enjoyed the dives.

I did not find deep or wreck particularly useful, and I think they may actually encourage diving past your training.

I found Nitrox useful since I knew nothing about gas mixing at the time. Later, taking Advanced Nitrox and Decompression was a book exercise since I was already doing those dives in caves.

I should take a Trimix course so I can legalize the helium bottle in my garage :)

Andrew hit the nail on the head, a cave certified instructor would be ideal. Unfortunately, as some have mentioned, an AOW card is almost a necessary evil, as it will make life a lot easier if you do any OW diving. So, IMHO, it would be your best bet to take the course as Andrew described.

Someone like Leslie would be what you are looking for, ie, someone with the correct skill set and attitude to make it worth your while.

Jay

Quote:

---

Originally Posted by aainslie

Ya know, it's all about the instructor.

If you can find an instructor with a cave cert (not necessarily at instructor level), then do it with them. Tell them of your intention. They will use the AOW dives to help you develop useful skills for cave. Deep, navigation, nitrox, search and recovery amongst others - you could make this a really nice pre-cave primer. if they're cave or wreck certified, they'll help critique your finning technique at the same time. it's not in the syllabus, but an instructor with the right background will help you do this.

But use the average OW instructor, and I'll agree that you won't learn as much. Something, but not as much.

So.. do your homework, find the right instructor, and you'll learn plenty... AND have a useful cert for when you want to do a wreck or a deep dive off a boat, and they want to see the AOW cert. That IMHO would be the most useful way to spend your money

---

Quote:

---

Originally Posted by Jay

Andrew hit the nail on the head, a cave certified instructor would be ideal. Unfortunately, as some have mentioned, an AOW card is almost a necessary evil, as it will make life a lot easier if you do any OW diving. So, IMHO, it would be your best bet to take the course as Andrew described.

Someone like Leslie would be what you are looking for, ie, someone with the correct skill set and attitude to make it worth your while.

Jay

---

I agree. Leslie [runawaylobster] would get you in tune with the skill set you are looking for to go forward with overheard training AND get that silly AOW card that can be very necessary on most dive boats...especially cattle boats.

Quote:

---

Originally Posted by mmcauliffe

I agree. Leslie [runawaylobster] would get you in tune with the skill set you are looking for to go forward with overheard training AND get that silly AOW card that can be very necessary on most dive boats...especially cattle boats.

---

I, too, agree. I took AOW and Nitrox classes with an overhead certified instructor. It made a world of difference learning how not to be a Gumby. If you already have your certs, sorry, you know how not to be a Gumby, but can still glean a thing or two.

I learned to dive in the ocean, doing progressively deeper dives year round for about four years, before I started cave diving.

Those first four years of diving I obtained Advanced Open Water, Nitrox and Rescue Certifications; I obtained one new cert each year. Each class was well worth the money, but experience doing the dives is what put it all together. There is no better teacher than time and experience, but it will help you to have a guide along the way. Someone to help you fine tune buoyancy skills. Someone to critique your trim in the water. Someone to look at your gear setup and help you streamline it. Ultimately, this person should be someone who will encourage you, but someone who will also be honest with you. Be mindful of these things when choosing your diving mentors.

I had a few excellent mentors from the beginning of my diving experience thirteen years ago. This help and the sheer love of diving kept me in the water, refining basic skills, learning new skills, and then seeking new diving experiences. Many steps are progressive, building on what you have already mastered. Take the time to master your diving skills and don't rush your entry into technical diving. But most of all, enjoy the diving and the journey!

Quote:

---

Originally Posted by SuPrBuGmAn

If you have good OW buddies with good bouyancy, trim, experience, or cave diver friends who'll dive with you in OW water conditions - just mentor under them.

---

Why not take a class from an instructor who is doing the type of diving you strive to do? Not only will they know the best way to get there, but they have the instructional and leadership training that is completely absent in all non-instructor training (as it should be). Just because someone can do it, doesn't mean they can teach you how to do it.

Especially in the case of AOW, you don't always get the same results. Sure there may be alot of cave instructors out there teaching a great AOW class that are above and beyond the standard requirements and catered to the cave diver(future or present), but likely not so in the rest of the states. As I said before, I learned nothing from AOW because I was already doing the types of dives discussed through the course. My trim and bouyancy were already above par for the AOW course. Was my intructor to blame? No, divers not diving regularly learned alot - he taught the course to the standards and likely a bit above. AOW is not an advanced course, its meant for the vacation diver and newer divers IMO. In the context of this thread the OP already seems to have atleast a bit of experience in the water, so the run-of-the-mill AOW course will likely be quite redundant and fruitless. I'll say it again, IMO.

At that point in training, I simply preffered diving often in different conditions to taking a course. The OW agencies aren't teaching anything you can't figure out naturally.

I learned more about perfecting good bouyancy and trim by simply watching better divers. Just being in the water with them helped fine tune things.

Quote:

---

Originally Posted by OneBrightGator

Just because someone can do it, doesn't mean they can teach you how to do it.

---

Sometimes they are teaching me without even knowing :) Certainly you can learn without an instructor.

being that all agency’s limit Open Water Divers to a Max depth of 60ft NDL and AWO to a max depth of 130ft NDL.

Being that an instructor certifying an OW Diver to Cavern is violating OW Certification Standards that instructor will be Liable if that person ever has an accident at least until another instructor violates standards and gives them a higher certification!

As a Cavern Instructor I will/would never accept an OW Diver into Cavern Training, not to mention that it violates the standards NAUI Cavern Diver Course.

Quote:

---

Originally Posted by billyf

being that all agency’s limit Open Water Divers to a Max depth of 60ft NDL and AWO to a max depth of 130ft NDL.

---

It doesn't say that anywhere in my SSI OW manual.

Quote:

---

Originally Posted by billyf

being that all agency’s limit Open Water Divers to a Max depth of 60ft NDL and AWO to a max depth of 130ft NDL.

Being that an instructor certifying an OW Diver to Cavern is violating OW Certification Standards that instructor will be Liable if that person ever has an accident at least until another instructor violates standards and gives them a higher certification!

As a Cavern Instructor I will/would never accept an OW Diver into Cavern Training, not to mention that it violates the standards NAUI Cavern Diver Course.

---

Quote:

---

Cavern Diving
The cavern diving course is taught in a minimum of two days and includes classroom lectures, field exercises, open water line drills and a minimum of four cavern dives. This course emphasizes planning, procedures, environment, propulsion techniques, buoyancy skills, problem solving, equipment modification and the focuses on the specialized needs of the cavern diver.

Purpose: To teach the safe exploration of the cavern environment within specified limits. The course develops and establishes minimum skills, knowledge, dive planning abilities, problem solving procedures and the basic abilities to safely cavern dive.

Prerequisites: Advanced open water or equivalent or 15 logged non training open water dives with open water certification.

---

Wouldn't the cavern cert override the OW in this case, similar to taking a OW cert diver to 80ft deep during their AOW course? IIRC the NACD suggests a max depth of either 100 or 130ft after taking the cavern course.

Quote:

---

Originally Posted by SuPrBuGmAn

It doesn't say that anywhere in my SSI OW manual.

---

Not sure what exactly they recommend, but in their nitrox course that I'm currently taking, they seem to rely more on a calculated ppo2 than picking a random magic number like 60ft. A quick google search made it seem like the magic number is 18 meters.

NACD cavern has a max depth of 100', TDI will allow 130', but suggests staying shallower than 100'.

My SSI OW booklet suggests staying shallower than 100', but doesn't stipulate a max depth aside from staying within NDL recreational limits(130' on air). LOL.

Quote:

---

Originally Posted by SuPrBuGmAn

NACD cavern has a max depth of 100', TDI will allow 130', but suggests staying shallower than 100'.

My SSI OW booklet suggests staying shallower than 100', but doesn't stipulate a max depth aside from staying within NDL recreational limits(130' on air). LOL.

---

That seems a lot more reasonable than saying 60ft limit in my opinion and from my observation....I've yet to hear what dangers are present at 80ft that are not present at 60ft. I still kind of find it funny that 130ft is the safe recreational limit on air (ppo2 of 1.037), and their safe limit on ean36 is 94ft (ppo2 of 1.39). I'll admit to being a n00b with this stuff, but it seems random to say the least. Overhead training limits make sense to me, but OW have always left me wondering "why". If an instructor could fill us in, I'd be interested to hear the explanation.

You have to take more into account than ppO levels, the narcotic effect of air is generally accepted as being much worse in the 100+' range.

Narc'd and in an overhead... :/

Quote:

---

Originally Posted by SuPrBuGmAn

the narcotic effect of air is generally accepted as being much worse in the 100+' range.

---

Is there a known reason why, or is this something divers have observed and an explanation hasn't been found yet?

Quote:

---

Originally Posted by jj1987

Is there a known reason why, or is this something divers have observed and an explanation hasn't been found yet?

---

They'll cover that in your AOW class.

They shoulda covered that in your OW class :/

Quote:

---

Originally Posted by SuPrBuGmAn

They shoulda covered that in your OW class :/

---

In our OW class we discussed that oxygen tox, and were told that dives below 100ft had an increased risk to the central nervous system, causing convulsions and other things of that nature. I don't think we went into what caused this, but were given the guidelines and told to obey them. Maybe I was a bad student, or maybe it wasn't covered, but I was under the impression that your body absorbed an exponentially greater amount of oxygen as more pressure builds up, but I never fully understood why.

Were you saying that the ppo2 formula is incorrect after a certain depth and the danger becomes higher, or that the effects of being narced increase with depth due to other factors like lack of light, color shifts as certain wavelengths dissapear, more pressure on your body, etc (I know these types of things can increase the effects of alcohol and drugs)?

The reason I'm wondering here, is that the ssi nitrox class I'm currently in doesn't seem to enforce depth limits as much as it says to just watch out for your ppo2, and keep it under a 1.4. Let's say you're diving air at 100ft, your ppo2 is .85, and a 36% nitrox blend is higher than that at 57ft with a ppo2 of .98, yet you're well within the "safe" limit, as you're still under 1.1 (or 1.4). I'm sorry if I'm being ignorant here, it just seems there's an external factor I'm not considering.

Quote:

---

Originally Posted by jj1987

In our OW class we discussed that oxygen tox, and were told that dives below 100ft had an increased risk to the central nervous system, causing convulsions and other things of that nature. I don't think we went into what caused this, but were given the guidelines and told to obey them. Maybe I was a bad student, or maybe it wasn't covered, but I was under the impression that your body absorbed an exponentially greater amount of oxygen as more pressure builds up, but I never fully understood why.

Were you saying that the ppo2 formula is incorrect after a certain depth and the danger becomes higher, or that the effects of being narced increase with depth due to other factors like lack of light, color shifts as certain wavelengths dissapear, more pressure on your body, etc (I know these types of things can increase the effects of alcohol and drugs)?

The reason I'm wondering here, is that the ssi nitrox class I'm currently in doesn't seem to enforce depth limits as much as it says to just watch out for your ppo2, and keep it under a 1.4. Let's say you're diving air at 100ft, your ppo2 is .85, and a 36% nitrox blend is higher than that at 57ft with a ppo2 of .98, yet you're well within the "safe" limit, as you're still under 1.1 (or 1.4). I'm sorry if I'm being ignorant here, it just seems there's an external factor I'm not considering.

---

O2 is not the only determinating factor. You have to include the PP of nitrogen and the affect it has on you. This should have been covered in your basic OW class. Although, the answers you seek are only a good Nitrox class away. Also, when I teach an AOW class, I explain the effects of Nitrogen at depth, and the reasons behind our "diving depth limits" for OW divers following NDL's.

I applaud your enthusiasm, but please don't try bypass classes by reading threads. There's a big difference between the internet and real life.

Safe Diving

Quote:

---

Originally Posted by Mike Edmonston

O2 is not the only determinating factor. You have to include the PP of nitrogen and the affect it has on you. This should have been covered in your basic OW class. Although, the answers you seek are only a good Nitrox class away. Also, when I teach an AOW class, I explain the effects of Nitrogen at depth, and the reasons behind our "diving depth limits" for OW divers following NDL's.

I applaud your enthusiasm, but please don't try bypass classes by reading threads. There's a big difference between the internet and real life.

Safe Diving

---

Understood, thanks for your response. :-D

Unfortunately I can't blame this one on my OW instructor but rather me having a brain fart, after you mentioned that I recall him going over daltons law and how it relates to partial pressures, plus chem class covered this on the first week as well. I had let nitrogen completely slip my mind here while posting, since so much of the focus on the nitrox class was oxygen. I'm guessing since oxygen tox is the more pressing issue on nitrox, that's why it's mentioned more, I guess that was a stupid question I could have avoided asking with a bit more thinking. I've been reading way too many nitrox discussions the past few days that I think I caught myself fumbling ox tox and nitrogen narcosis as one in the same. I guess that's the downside of the springs being flooded and having way too much internet time.

Give me one second and I'll review my notes and answer this question for myself (and for anyone else who might stumble across the thread).

OK heres the edit....I didn't see any problems we had to work out from my OW notes, but I still have my notebook from college chem, which had notes on this, and the formula was in my OW notes, so putting the two together I think I've explained my own question.
ppn2=[(d+33)/33]*.79
ppn2= partial pressure of nitrogen
d= depth in salt water ft
We add 33 to include the 1atm of surface pressure
We multiply by .79 for the nitrogen content in the air.

So the rec limit for ppn2 is around 3 (I googled it, it appears some agency's are higher than others, but all around 3).
3=[(d+33)/33]*.79
3.797=(d+33)/33
125.316=d+33
d=92.316

So around 92ft we start to come into the >3 range of ppn2. 36% nitrox would have a ppn2 of around 2.44, so ox tox would come into play before nitrogen issues would. Hopefully I'm right this time. This is why I hate giving people round numbers to memorize, it's so easy to have a brain fart and forget what they mean... :(

Quote:

---

Originally Posted by jj1987

That seems a lot more reasonable than saying 60ft limit in my opinion and from my observation....I've yet to hear what dangers are present at 80ft that are not present at 60ft. I still kind of find it funny that 130ft is the safe recreational limit on air (ppo2 of 1.037), and their safe limit on ean36 is 94ft (ppo2 of 1.39). I'll admit to being a n00b with this stuff, but it seems random to say the least. Overhead training limits make sense to me, but OW have always left me wondering "why". If an instructor could fill us in, I'd be interested to hear the explanation.

---

there are 20 feet worth of more danger. if no feet is 1 unit of danger, then 33 is 2 units of danger, 66 is 3 units of danger, 99 is 4 units of danger. Danger multiples with depth, it changes nature too, but just the fact that depth = pressure = danger should be enough to clue you in.

ppo2 is not the only consideration. it is not random. don't do the dives if they make you wonder why.

-skip

You weren't a bad student, most OW instructors don't cover narcosis because it simply isn't a factor when diving within OW training limits. Since the onset of narcosis typically takes place for the majority of divers at 100' or greater depths, it is typically included in AOW training.

Maybe I'm missing something or I have a short memory having taken both classes more than 15 years ago, but I'm sure narcosis wasn't heavily covered in OW.

Take the classes and take your time. You can't rush experience.

Quote:

---

Originally Posted by SuPrBuGmAn

It doesn't say that anywhere in my SSI OW manual.

---

I took my SSI OW from Hal Watts shop in Orlando in '87. I don't remember any depth limits being taught or in the book (except my deco charts only showed to 190'). As far as I knew the certification series started with OW, Deep 1, Deep 2, Deep 3, Deep 4, Deep 5, Deep 6, Deep 7 - all on air of course. :diver I'm not sure if AOW was included on the menu or not.

Well at least I was never taught to fear the depth/narcosis.

But my manual is only from '03, I wouldn't think things would have changed that much since then? *shrugs*

Quote:

---

Originally Posted by Gary

As far as I knew the certification series started with OW, Deep 1, Deep 2, Deep 3, Deep 4, Deep 5, Deep 6, Deep 7

---

ROFL! :clapper

Quote:

---

Originally Posted by jj1987

ROFL! :clapper

---

You laugh...He's being serious.

Maybe I missed something here - JJ, how many dives have you had since your OW? More importantly, how many of those were in less than ideal conditions? (i.e. At night at the least. Even better would be in mud lake-viz that may not be too deep, but where you have to learn to trust your gauges.) Those were all stepping stones. Do you feel you have nothing else to learn? Eighty dollars is a small price to pay. Especially small if you think caving is the way to go.

By your handle, I'm going to guess you're 21-ish. Remember when you first learned to drive a car? Have you learned anything in the last 5 years just by being on the road? (Remember that time when... ) *Nothing* beats experience.

I remember my AOW instructor as someone there to be impressed with my skills after just 8 post OW dives. You know, the stuff we know intuitively, like knowing how to navigate blindly by compass alone, dropping deep out of the sun light (mud lake) without any increase in my breathing rate, and doing flawless math problems at depth. That's because narcosis doesn't affect me. ;-)

-Tom

Quote:

---

Originally Posted by rec2tec

Maybe I missed something here - JJ, how many dives have you had since your OW? More importantly, how many of those were in less than ideal conditions? (i.e. At night at the least. Even better would be in mud lake-viz that may not be too deep, but where you have to learn to trust your gauges.)

---

I have 4 dives in Kingsley lake to the helicopter that's sunk, that's about 10ft vis at the bottom there, and we do a night dive every time we go to Ginnie, 10 would be a very low guess, and I've done a few in the keys. I have a few 100 cavern dives to go along with those, but I'd consider those most all ideal conditions.

I think I'm ready for Intro to cave, or I wouldn't be buying gear and saving up for it, but I've also read too many newspaper articles about cave accidents to continue forward with training if those who are already cave diving are convinced I shouldn't, hence why I asked the question. :yawinkle:


On a positive note, I'm now Nitrox certified as of a few hours ago :)!
After reading this link (click) and the SSI manual, the SSI test was a breeeeeze that took about 15 minutes to finish. Big thanks to those of you that PM'ed me with the link and suggestions on what to pay attention to when going through the course materials. I found it really odd that you never have to know a single bit of the math behind the tables to pass the test, basically if you can calculate 2 dives (switching gas mixture on each), and know how to calculate your CNS clock time and MOD with the tables, you've passed the test. I'm anxious to get a few real world situations under my belt now.

Quote:

---

Originally Posted by jj1987

I found it really odd that you never have to know a single bit of the math behind the tables to pass the test

---

That's an agency thing. There are some agencies that not only present the equations but also include them in the test. You just chose the wrong agency/instructor.

When I was working full-time at a shop I noticed something I disagreed with. There were fifty questions on the open water test, and you had to make an 80 to pass, so you could miss ten questions. But there were only eight questions where you had to do the tables to arrive at the answer. So you could miss EVERY question on the tables and still pass.

If I were in charge, you would have to make an 80 on the tables section, plus an 80 on the other part.

Quote:

---

Originally Posted by Slüdge

When I was working full-time at a shop I noticed something I disagreed with. There were fifty questions on the open water test, and you had to make an 80 to pass, so you could miss ten questions. But there were only eight questions where you had to do the tables to arrive at the answer. So you could miss EVERY question on the tables and still pass.

---

I think I've dove with some of those people.....

NAUI has a similar pass requirement (80%), but I've added 50 more questions for 100 total, and require students to get all the dive table questions correct or they don't pass! naui allows this kind of flexibility. as everyone knows, it's the instructor, not the agency, that's important.

-skip

Quote:

---

Originally Posted by Slüdge

When I was working full-time at a shop I noticed something I disagreed with. There were fifty questions on the open water test, and you had to make an 80 to pass, so you could miss ten questions. But there were only eight questions where you had to do the tables to arrive at the answer. So you could miss EVERY question on the tables and still pass.

If I were in charge, you would have to make an 80 on the tables section, plus an 80 on the other part.

---

Last night one girl didn't get the dive tables, so they agreed she would get a dive computer and she got the c card, but I couldn't say it was creating an extra danger, she didn't know how to use the air tables anyways. Besides, she had more c cards than me, OW, AOW, and rescue :roll:

Nitrox seemed fairly straight forward. I'll just be sure to get my tanks filled and discuss my dive plan with the more tech diving oriented shops like Lloyd's, Steamboat, and the one in High springs who's name escapes me, I really appreciate how they have knowledgeable divers on staff that always seem willing to help.

Quote:

---

Originally Posted by billyf

being that all agency’s limit Open Water Divers to a Max depth of 60ft NDL and AWO to a max depth of 130ft NDL.

Being that an instructor certifying an OW Diver to Cavern is violating OW Certification Standards that instructor will be Liable if that person ever has an accident at least until another instructor violates standards and gives them a higher certification!

As a Cavern Instructor I will/would never accept an OW Diver into Cavern Training, not to mention that it violates the standards NAUI Cavern Diver Course.

---

With that logic, isn't an OW shop violating the "must see your C card to give you air" standard when they rent a tank to a student in the OW class? I understand that you want good divers in your class for safety reasons but I think you are extrapolating laws out of suggestions.

Quote:

---

Originally Posted by jj1987

Last night one girl didn't get the dive tables, so they agreed she would get a dive computer and she got the c card, but I couldn't say it was creating an extra danger, she didn't know how to use the air tables anyways. Besides, she had more c cards than me, OW, AOW, and rescue :roll:

Nitrox seemed fairly straight forward. I'll just be sure to get my tanks filled and discuss my dive plan with the more tech diving oriented shops like Lloyd's, Steamboat, and the one in High springs who's name escapes me, I really appreciate how they have knowledgeable divers on staff that always seem willing to help.

---

Sounds like she shouldn't have gotten the C card. Maybe the marginal danger wasn't that great but the total danger sounds, eh, greater than 0 for sure! Not certain if she should be allowed near a bathtub or a pool with scuba gear if she doesn't understand how to use tables...

Lloyd is expensive. Waterworld isn't necessarily tech oriented but several of their employees and instructors are cave divers and some of them work at Dive Rite too. Extreme Exposure is in High Springs but don't shop there if you don't have all black gear with blue H's! :) (I'm kidding, but not too much...) (they are also pricey, but give good air and they are good divers there) Cave Excursions East is about 10 minutes away from EE and they have the cheapest air in the county (I think they are about a penny/cubic foot cheaper than Amigos' for nitrox, but I don't recall exactly. I don't go by Amigo's much but if you are out that way I'd reccomend supporting them, great business too!!) as far as I am aware and are a great shop.

What does cave excursions east charge for nitrox?

Now you're splitting hairs.

All the shops in cave country are within a penny or two of each other. You will spend more in time and gasoline driving to the cheapest place. Just go the the nearest, most convenient shop that sells it by the cu/ft. Which is, as far as I know, every dive shop within 100 mile radius of Branford.

I only mention Branford because that seems to be the epicenter. More or less equal distance between Luraville and High Springs.

CEE is $.09/cu.ft., Amigos is either the same or $.10. I go to CEE usually as it's close or on the way to several of the sites I dive, but if I were out that way it would be my pleasure to support Amigos as well!

EE I haven't had amazingly pleasant experiences with but I won't speak badly of them, per se. I have friends who only shop there and they get treated just fine.

Well this is what N.A.C.D. REQUIRES !!!!!!!!!!!!!!!!! I think the word they use here is (equivalent). Not trying to step on any toes just saying that I think it is up to the instructor.


Cavern Diving
The cavern diving course is taught in a minimum of two days and includes classroom lectures, field exercises, open water line drills and a minimum of four cavern dives. This course emphasizes planning, procedures, environment, propulsion techniques, buoyancy skills, problem solving, equipment modification and the focuses on the specialized needs of the cavern diver.

Purpose: To teach the safe exploration of the cavern environment within specified limits. The course develops and establishes minimum skills, knowledge, dive planning abilities, problem solving procedures and the basic abilities to safely cavern dive.

Prerequisites: Advanced open water or equivalent or 15 logged non training open water dives with open water certification.