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bigman241
08-14-2009, 00:43
What are the norms for depth limits for ow and aow. How deep do most people recommend newbis stay around

Lone Frogman
08-14-2009, 04:17
60 and 130

snagel
08-14-2009, 05:19
For open water, technically you are not to go deeper than 60'. In Advance Open Water you will have to do a deep dive of atleast 60 feet and more likely 80 feet depending on the set up. Recreational divers are not to exceed 130'.

Once again, depth of dive will depend on your dive plan and your comfort level. I can tell you that after OW, I dove many dives no deeper than 30 feet. Once my comfort level got better, I got deeper.

Snagel

jet126
08-14-2009, 05:49
Once you get comfortable diving you will most likely find the depth that works best for your style. I'm a fish-hugger and see the prettiest, most fish in the 30-60 ft. range. That is totally perfect for me. But if you like poking around wrecks, you'll probably want to go deeper as a lot of wrecks are in 100 ft or more.
Remember also that the deeper you go, the shorter your bottom time. So there's that to consider as well.

PTAaron
08-14-2009, 06:06
Technically it is 60ft OW and beyond that you need AOW. There are no scuba police, but the dive op may limit the max depth depending on your cert. On our first post cert dives we were in Jamaica... and we were at 60-70ft on some dives with no problem, and felt very comfortable doing it. The nearly unlimited visibility helped. Our DM (guided dives) emphasized the 60ft limit - but when he saw something interesting would call us over to look at it at 60-70ft. On quarry dives we have mostly stayed in the 25-30ft range because 1) the viz stinks below the thermocline and 2) it is too cold below the thermocline.
It all depends on how you feel in the situation. Caribbean diving with unlimited viz and no thermocline makes it easier to go beyond your experience level if you aren't careful.

Scuba Pete
08-14-2009, 08:02
I beleive that it is 60' for OW, 90' for AOW, and anything beyond that is deep diver. There is alot to be said for where the depth is. I went to 100' on my 3rd dive after ow certification in the Cayman islands. I went to 100' in a quarry in ohio. There is a huge difference. I beleive that the depth ratings are recomendations, not rules. Like everything in diving there is no scuba police waiting at 60 to check to see if you have an AOW card or anything else. Unless there is a wreck at 100', there is nothing that you cant see at a shallower depth. You would also get more time to enjoy whats down there.

Scuba Pete
08-14-2009, 08:08
Technically it is 60ft OW and beyond that you need AOW. There are no scuba police, but the dive op may limit the max depth depending on your cert. On our first post cert dives we were in Jamaica... and we were at 60-70ft on some dives with no problem, and felt very comfortable doing it. The nearly unlimited visibility helped. Our DM (guided dives) emphasized the 60ft limit - but when he saw something interesting would call us over to look at it at 60-70ft. On quarry dives we have mostly stayed in the 25-30ft range because 1) the viz stinks below the thermocline and 2) it is too cold below the thermocline.
It all depends on how you feel in the situation. Caribbean diving with unlimited viz and no thermocline makes it easier to go beyond your experience level if you aren't careful.

I have found that the vis gets better below the thermocline. Or at least the one in the 30-35' range. We did my first dryglove dive last weekend. Man why did i wait to use them. My hands were warm and i could actually move them and manipulate better with them. Needless to say we stayed under the thermocline to help with keeping cool. Plus the vis was better. Above was around 5-10, below was more like 10-15. There were deeper spots but didnt make it to them. I would imagine around the 80' area the vise was 20-30 like it has been before.

Quero
08-14-2009, 11:20
I'm a PADI instructor. My agency recommends depth limits of 18 meters/60 feet for Open Water divers. For Advanced Open Water divers, the recommended limit is 30 meters/100 feet, with a contingency depth limit of 40 meters/130 feet.

As PTAaron states, there are no scuba police, but each boat/dive leader can impose requirements for credentials for deep diving (beyond 18 m/60 ft) as part of their policies and procedures, along with requirements for credentials to do night dives or other dives that present challenges that are not covered in OW courses.

CompuDude
08-14-2009, 13:33
I'm a PADI instructor. My agency recommends depth limits of 18 meters/60 feet for Open Water divers. For Advanced Open Water divers, the recommended limit is 30 meters/100 feet, with a contingency depth limit of 40 meters/130 feet.

As PTAaron states, there are no scuba police, but each boat/dive leader can impose requirements for credentials for deep diving (beyond 18 m/60 ft) as part of their policies and procedures, along with requirements for credentials to do night dives or other dives that present challenges that are not covered in OW courses.

Yes, for PADI, it's 60' for OW and 100' for AOW, but to go up to the max recreational limit (and beyond 100'), they recommend you get the Deep Diver specialty (130' limit, 140' emergency contingency).

With the exception of wrecks, there vast majority of the best stuff to see lies in the 60' and shallower range. Deeper than that and your NDL bottom times start getting dramatically shorter, both from a nitrogen loading standpoint, and a gas capacity standpoint, unless you seek advanced training to technical decompression diving with trimix, double cylinders, etc.

IMO, it's best for newer divers to stick to the 60' max for a while until they're more comfortable, even if they go directly into AOW (which I generally recommend should wait at least 10 dives, personally, although this recommendation can change depending individual circumstances). I plan to keep my wife restricted to 60' max until she has 10-15 dives under her belt and can show me she's comfortable in the water and managing her buoyancy reasonably well, before adding the increased risk of deeper dives. An uncontrolled ascent is never good, but it's better that it happen from a relatively shallow depth than 100'.

it_mike
08-14-2009, 13:44
Here's one for you...

I find my best dives are in less than 30 fsw. I enjoy looking at the smaller aquatic life; corals, and the life they host, grow best with good lighting. This precludes any significant depth. Take a dive on the leeward side of the keys. An 80 will last an hour and a half while you check out the bugs and growth.

I'll also say that my most interactive dives happen in less than 20 fsw, but that's because the aquarium tanks aren't any deeper! :D

PTAaron
08-14-2009, 13:50
Here's one for you...

I find my best dives are in less than 30 fsw. I enjoy looking at the smaller aquatic life; corals, and the life they host, grow best with good lighting. This precludes any significant depth. Take a dive on the leeward side of the keys. An 80 will last an hour and a half while you check out the bugs and growth.

I'll also say that my most interactive dives happen in less than 20 fsw, but that's because the aquarium tanks aren't any deeper! :D
I'm pretty sure an 80 won't last me an hour and a half unless I'm using it at the surface ;)

Scuba Pete
08-14-2009, 13:58
An 80 will last me 90 mins with some left at 20'. I did a dive for 89 mins max depth of 27', but i did have double 80's we got too bored and came up early. The plan was a 120 min dive.

CompuDude
08-14-2009, 14:17
Here's one for you...

I find my best dives are in less than 30 fsw. I enjoy looking at the smaller aquatic life; corals, and the life they host, grow best with good lighting. This precludes any significant depth. Take a dive on the leeward side of the keys. An 80 will last an hour and a half while you check out the bugs and growth.

Depends on where you're diving, of course. Some site, absolutely, you can spend hours at 15' and never be bored. Other sites have nothing until you get down deeper, so you have no choice in the matter.

Most wrecks tend to be in a least 40-60', if not considerably deeper.

Lulubelle
08-14-2009, 14:35
Personal depth limits within recreational limits should not be arbitrary IMHO. It depends on so many factors, skill level coming out of OW, fitness levels, ocean versus fresh water, general comfort in the water, swimming abilities, etc.

Our wrecks are deep, most between 100-130 feet. Coming out of OW, I wanted to keep diving.

My first dive out of OW was to 128 feet on the Papoose. This would be a really bad idea for many and I'm sure some think it stupid of me to have done this. However, I was very well prepared, my buddy and the op were aware of my level, my buddy had over 500 dives most of which were in the Atlantic. I also grew up swimming in the Atlantic here in NC and pulled my first rip tide victim out of the water at age 10. I find land daunting but the water to be a place where I am completely at home. There was an instructor in the group who said I looked like I had been diving at those depths for 10 years. Still, 50 dives in, I will not insta buddy here due to our depths and conditions. I am very cautious and don't push limits.

I agree with previous posts that say that most of the good stuff is between 30-60 feet in tropical environments. I don't go deeper unless there is a reason to go deeper.

So do an honest assessment while you are in OW and define your parameters accordingly.

Jack Hammer
08-15-2009, 00:28
It's common for new divers to want to go deeper, until they do it and find that for a lot of recreational dives there really isn't much reason to go deeper. There are some great wrecks and aquatic life to see at 40', plus I can easily stay for well over an hour at that depth on a single tank and explore.

As mentioned, with deeper dives you start running into NDL limits and other complications quickly. I did a recreational dive to 135' to see a great wreck and even with nitrox I only got something like 12 minutes BT, over 2 minutes of that was used up decending. We spent just under 9 minutes on the wreck before we had to start ascent. If that had been in half that depth I could have spent over an hour exploring. I've had several great dives where our max depth was less than 25' and we averaged something like 17'.

Quero
08-15-2009, 06:49
Yes, for PADI, it's 60' for OW and 100' for AOW, but to go up to the max recreational limit (and beyond 100'), they recommend you get the Deep Diver specialty (130' limit, 140' emergency contingency).


CompuDude, could you specify an IM reference page with this information? I'm especially interested in the 140' contingency depth for the Deep Diver rating. The flat air table does list that depth (actually, my metric one goes "only" to 42 meters/138 feet). But as a Deep Diver Specialty Instructor, while teaching I've always stuck to the PADI "party line" that 130' is the absolute maximum for recreational diving. I would really appreciate reading the relevant part of the IM so that I give the correct information to my students.

Lulubelle
08-15-2009, 12:53
Yes, for PADI, it's 60' for OW and 100' for AOW, but to go up to the max recreational limit (and beyond 100'), they recommend you get the Deep Diver specialty (130' limit, 140' emergency contingency).


CompuDude, could you specify an IM reference page with this information? I'm especially interested in the 140' contingency depth for the Deep Diver rating. The flat air table does list that depth (actually, my metric one goes "only" to 42 meters/138 feet). But as a Deep Diver Specialty Instructor, while teaching I've always stuck to the PADI "party line" that 130' is the absolute maximum for recreational diving. I would really appreciate reading the relevant part of the IM so that I give the correct information to my students.

I'd be interested to know what the consensus amongst agencies is, but more importantly, what the consensus is from DAN or other Scuba organizations which are not selling classes.

I'm a big believer in classes, don't get me wrong, but there is some redundant content in some of them and I certainly don't think I need to take all of them. For instance, I took a wreck class with Naui. The instructor used the TDI Advanced Wreck Manual. I'm fairly sure we covered most if not all of the content from a Deep Diving specialty course. It was a very good and in depth course. I'm sure some of this varies instructor by instructor. I can't see the wisdom in taking the Deep Diving class at this point after having taken this wreck class onsite in NC with checkout dives at depths exceeding 100 feet.

I don't go beyond 130 feet or dive beyond my NDL. I plan to get some more training in the near future to be able to push beyond rec limits if and only if there is a compelling reason to do so.

in_cavediver
08-15-2009, 17:51
My personal feeling is that standard scuba rec divers use is good for 80-100' max. Beyond that, you start 'pushing' things with gas usage, reserves and options. Do you want to try a CESA at 100'?

That said, there are good ways to go deeper. Advanced Nitrox (IANTD) is a great class - even if you never want to really exceed rec diving limits. It gives you the tools and information to do deeper dives.

(Then again, maybe its because I *just* got back from Thunder Bay diving wrecks in the 80-110' range and am eyeing those in the 130-160' range for the next trip...)

Smashee
08-15-2009, 17:56
I'd be interested to know what the consensus amongst agencies is, but more importantly, what the consensus is from DAN or other Scuba organizations which are not selling classes.

BSAC - Recommended maximum for Ocean Diver (OW equivalent) is 20m (65ft) Sports Diver (AOW+) is 35m (115ft) and Dive Leader is 55m (180ft). This is still classed as recreational diving. Further depth certification can be gained through doing Trimix or Extended Range courses, but 55m is the limit on air as we work to a fairly conservative max. ppO2.

Decompression theory is taught almost from day one and simulated deco dives/deco planning is encouraged even if you can't hit your NDL. The skills needed for proper dive-planning and being able to hold stops are valuable at any level of experience.

Quero
08-15-2009, 22:02
I'd be interested to know what the consensus amongst agencies is, but more importantly, what the consensus is from DAN or other Scuba organizations which are not selling classes.

Lulubelle, the depth "limits" are fairly standard across agencies since a large number of the major agencies subscribe to the general standards set out by the RSTC/WRSTC.*

One important point: the limits are actually training limits that instructors must adhere to and that divers, once certified, are recommended to adopt. So while PADI instructors may not conduct training dives for AOW students beyond 30 m/100 ft, and the AOW certified diver is encouraged to adopt that limit him/herself, the AOW book actually states that the "optimal" recreational deep diving limit is 30 m/100 ft and the "absolute maximum" recreational limit is 40 m/130 ft.

Operators can impose their own policies, and of course some countries have laws determining maximum depths (e.g., Maldives, where the max is 30 m/100 ft).

*WRSTC affiliated agencies:
ACUC, BARAKUDA, DAN Europe, IDEA, NASDS, PADI, PDIC, PSS, SDI, SNSI, SSI, and the former YSCUBA. Note that other major agencies such as BSAC CMAS and IANTD are not affiliated.

Jack Hammer
08-16-2009, 11:13
Yes, for PADI, it's 60' for OW and 100' for AOW, but to go up to the max recreational limit (and beyond 100'), they recommend you get the Deep Diver specialty (130' limit, 140' emergency contingency).


CompuDude, could you specify an IM reference page with this information? I'm especially interested in the 140' contingency depth for the Deep Diver rating. The flat air table does list that depth (actually, my metric one goes "only" to 42 meters/138 feet). But as a Deep Diver Specialty Instructor, while teaching I've always stuck to the PADI "party line" that 130' is the absolute maximum for recreational diving. I would really appreciate reading the relevant part of the IM so that I give the correct information to my students.
not sure if or where it is in any book, but in my aow class they told me the same things Compudude mentions. 130' as the absolute max for recreational diving plus I was told the 140' is on the chart for emergency planning purposes only (or if you accidentally go too deep).

Quero
08-16-2009, 14:25
not sure if or where it is in any book, but in my aow class they told me the same things Compudude mentions. 130' as the absolute max for recreational diving plus I was told the 140' is on the chart for emergency planning purposes only (or if you accidentally go too deep).
Yes, Jack, what you said about the table is mainly right, except you need to take out the word "planning". But that's not really what I understood CompuDude to say. What I thought he said was that 100 was the max depth for AOW, and 130/140 was the max depth for Deep Diver Specialty.

Jack Hammer
08-16-2009, 16:51
not sure if or where it is in any book, but in my aow class they told me the same things Compudude mentions. 130' as the absolute max for recreational diving plus I was told the 140' is on the chart for emergency planning purposes only (or if you accidentally go too deep).
Yes, Jack, what you said about the table is mainly right, except you need to take out the word "planning". But that's not really what I understood CompuDude to say. What I thought he said was that 100 was the max depth for AOW, and 130/140 was the max depth for Deep Diver Specialty.
Good catch on 'planning", not really the right choice of words on my part.

If you go to the PADI website it lists AOW as training for diving "typically anywhere from 18-30 metres/ 60-100 feet" (I vaguely recall this from my class). They list the deep diver specialty as training "Techniques for diving in the deeper range of 18-40 metres/ 60-130 feet".

Jack:smiley20:
(i'm just regurgitating what I read on their site, I'm not a DM and it's been a while since I took aow)

Quero
08-16-2009, 23:03
Hi again, Jack. Thanks for trying to help. As an instructor, I am familiar with what is on the website, in the manuals, and taught in the classes. However, nothing you have found (or stated that you recall) actually addresses my question.

My question was mainly about the mention of 140 ft/42 m, which I had never heard of as a recommended limit for any recreational rating. To try to solve the mystery (as I very much respect Kalani and figure he may have been referring to sources I couldn't put my finger on) I've been through the general Instructor Manual as well as the Specialty Instructor Manual backwards and forwards, and I can find no mention whatever of a recommended 140 ft/42 m depth limit for any dives. This is why I asked CompuDude if he had some information beyond what I was able to find.

I have finally come upon one single place where the deeper figures are mentioned. I quote from page 7 of the small booklet Instructions for Use: Recreational Dive Planner:


10. Limit your maximum depth to your training and experience level. As an Open Water Diver, limit your dives to a maximum depth of 18 meters. Divers with greater training and experience should generally limit themselves to a maximum depth of 30 meters. Divers with Deep Diver training and a reasonable objective may dive as deep as 40 meters. All dives should be planned as no decompression dives, and no dive should ever exceed the maximum depth limitation for recreational scuba--40 meters.
11. Never exceed the limits of the Recreational Dive Planner, and whenever possible avoid diving to the limits of the planner. 42 meters is for emergency purposes only. Do not dive to this depth.

captain
08-17-2009, 10:47
How did the 130 foot limit come about. Here is the real answer. The US Navy had scuba training before most certifying agencies were in existence with possibly the exception of LA County.
The Navy determined that 130 feet was the deepest depth scuba was suitable for because it was the deepest depth that divers using twin 90 cu/ft tanks had enough air to accomplish 15 to 30 minutes of meaningful work . Beyond 130 feet the air supply did not last long enough for anything more than a short 0 to 15 minutes of work. The agencies just adopted the Navy's guide lines but they reason was lost or translated into a safety issue.

CompuDude
08-17-2009, 13:41
Hi again, Jack. Thanks for trying to help. As an instructor, I am familiar with what is on the website, in the manuals, and taught in the classes. However, nothing you have found (or stated that you recall) actually addresses my question.

My question was mainly about the mention of 140 ft/42 m, which I had never heard of as a recommended limit for any recreational rating. To try to solve the mystery (as I very much respect Kalani and figure he may have been referring to sources I couldn't put my finger on) I've been through the general Instructor Manual as well as the Specialty Instructor Manual backwards and forwards, and I can find no mention whatever of a recommended 140 ft/42 m depth limit for any dives. This is why I asked CompuDude if he had some information beyond what I was able to find.

I have finally come upon one single place where the deeper figures are mentioned. I quote from page 7 of the small booklet Instructions for Use: Recreational Dive Planner:


10. Limit your maximum depth to your training and experience level. As an Open Water Diver, limit your dives to a maximum depth of 18 meters. Divers with greater training and experience should generally limit themselves to a maximum depth of 30 meters. Divers with Deep Diver training and a reasonable objective may dive as deep as 40 meters. All dives should be planned as no decompression dives, and no dive should ever exceed the maximum depth limitation for recreational scuba--40 meters.
11. Never exceed the limits of the Recreational Dive Planner, and whenever possible avoid diving to the limits of the planner. 42 meters is for emergency purposes only. Do not dive to this depth.

I don't know offhand if the 140' figure came directly from the instructor manual, but it was definitely discussed (verbally) by my instructor as part of either my DM course or as part of my Deep Specialty course (which they wanted me to take on the road to DM). Between the reference you found and the information included with the actual tables (the same information is printed directly on the plastic tables), however, I believe the answer can be reasonably inferred... that's why I referred to the 130' limit and the 140' contingency depth (for emergencies only, is what I meant, if that wasn't clear).

If I have a chance, I'll look through the instructor manual and see if there are any references, but I don't know that I can look any more thoroughly than you can through the same source materials. :)

rfortune
08-19-2009, 13:41
What are the norms for depth limits for ow and aow. How deep do most people recommend newbis stay around

My kids & I are newly certified OW (around 20 dives each).

We just got back from our first dive trip to Coz and after a "checkout dive" I registered 86' on our first boat dive the next morning and 98' on the first dive the following day. We went that deep because we were doing swimthroughs in Palancar Horseshoe and Columbia Deep.

I can tell you imho as a newbie, that 80-90 feet in the Caribbean is SIGNIFICANTLY "easier" than 60 feet in a 42deg quarry in Wisconsin. The unlimited vis and warm water does not give you the "oppressive" feeling that you can get in cold water with limited vis and 7mm suits, gloves, hood, etc...

I also will agree with others that deep does not always mean better - shallower can mean more bottom time & more critters.

Flatliner
08-19-2009, 14:05
I did the deep course very early. However, before doing it, I had done two 90+ dives. Actually found them more enjoyable than what I was used to. Skills are so much easier at deeper depths.

MSilvia
08-20-2009, 12:13
Remember also that the deeper you go, the shorter your bottom time.
The deeper you go, the shorter your NDLs, but that isn't necessarily mean shorter bottom time. Adv. Nitrox/Deco procedures class isn't just about going deeper... it can also help you get more time out of recreational depths.


Most wrecks tend to be in a least 40-60', if not considerably deeper.
A lot of wrecks in shallower water tend to get dynamited to remove navigation hazards.


BSAC - etc...
Sounds wonderful... it makes me wish their courses were more available state-side.


My question was mainly about the mention of 140 ft/42 m, which I had never heard of as a recommended limit for any recreational rating.
When I got my PADI OW cert back in the mid 1980s, a different RDP was used. The max depth (for contingency planning) on the table was 140', and deco times were provided for planning ascents if NDLs were missed. The course content seems to have been watered down quite a bit over the years... at the time, this stuff was taught to open water divers.

Quero
08-20-2009, 13:25
My question was mainly about the mention of 140 ft/42 m, which I had never heard of as a recommended limit for any recreational rating.
When I got my PADI OW cert back in the mid 1980s, a different RDP was used. The max depth (for contingency planning) on the table was 140', and deco times were provided for planning ascents if NDLs were missed. The course content seems to have been watered down quite a bit over the years... at the time, this stuff was taught to open water divers.Well, you got me curious, so I dug out my original table from my own OW course to take a look... it's version 1.0 with a copyright date of 1985. I compared it to a newer one, version 1.2, with a revision date of 2003. They both list the same depths, with the deepest NDLs given for 42 meters. Both also have emergency decompression information in the event that an NDL is breached. And yes, this stuff is still taught to open water divers.

Again, my post had to do with the notion that 140 feet was the recommended maximum depth for recreational divers with deep dive training (as opposed to recommended limits for other recreational ratings). As far as I know--and I still have not seen any actual reference to the contrary--the absolute maximum depth for planning any recreational dive is 130 feet, and the 140 ft column on the RDP is there not for planning but rather just in case a diver accidentally dips down a few more feet and needs to calculate pressure groups after the fact. I teach Deep Diving specialty and have never encountered any mention of 140 feet as a recommended maximum depth, so I simply wondered if CompuDude (or another reader) could point me to a source that I could consult for this recommendation. So far, the only sources mentioned by anybody seem to have been oral discussions during classes and the notation on the RDP/RDP booklet clearly stating: 42 meters is for emergency purposes only, do not dive to this depth.

Scuba Pete
08-20-2009, 14:42
My question was mainly about the mention of 140 ft/42 m, which I had never heard of as a recommended limit for any recreational rating.
When I got my PADI OW cert back in the mid 1980s, a different RDP was used. The max depth (for contingency planning) on the table was 140', and deco times were provided for planning ascents if NDLs were missed. The course content seems to have been watered down quite a bit over the years... at the time, this stuff was taught to open water divers.Well, you got me curious, so I dug out my original table from my own OW course to take a look... it's version 1.0 with a copyright date of 1985. I compared it to a newer one, version 1.2, with a revision date of 2003. They both list the same depths, with the deepest NDLs given for 42 meters. Both also have emergency decompression information in the event that an NDL is breached. And yes, this stuff is still taught to open water divers.

Again, my post had to do with the notion that 140 feet was the recommended maximum depth for recreational divers with deep dive training (as opposed to recommended limits for other recreational ratings). As far as I know--and I still have not seen any actual reference to the contrary--the absolute maximum depth for planning any recreational dive is 130 feet, and the 140 ft column on the RDP is there not for planning but rather just in case a diver accidentally dips down a few more feet and needs to calculate pressure groups after the fact. I teach Deep Diving specialty and have never encountered any mention of 140 feet as a recommended maximum depth, so I simply wondered if CompuDude (or another reader) could point me to a source that I could consult for this recommendation. So far, the only sources mentioned by anybody seem to have been oral discussions during classes and the notation on the RDP/RDP booklet clearly stating: 42 meters is for emergency purposes only, do not dive to this depth.

I think you misread Compudude's message "Yes, for PADI, it's 60' for OW and 100' for AOW, but to go up to the max recreational limit (and beyond 100'), they recommend you get the Deep Diver specialty (130' limit, 140' emergency contingency)."

I think you are arguing about the same thing. Different words, same message.

mitsuguy
08-20-2009, 14:46
My question was mainly about the mention of 140 ft/42 m, which I had never heard of as a recommended limit for any recreational rating.
When I got my PADI OW cert back in the mid 1980s, a different RDP was used. The max depth (for contingency planning) on the table was 140', and deco times were provided for planning ascents if NDLs were missed. The course content seems to have been watered down quite a bit over the years... at the time, this stuff was taught to open water divers.Well, you got me curious, so I dug out my original table from my own OW course to take a look... it's version 1.0 with a copyright date of 1985. I compared it to a newer one, version 1.2, with a revision date of 2003. They both list the same depths, with the deepest NDLs given for 42 meters. Both also have emergency decompression information in the event that an NDL is breached. And yes, this stuff is still taught to open water divers.

Again, my post had to do with the notion that 140 feet was the recommended maximum depth for recreational divers with deep dive training (as opposed to recommended limits for other recreational ratings). As far as I know--and I still have not seen any actual reference to the contrary--the absolute maximum depth for planning any recreational dive is 130 feet, and the 140 ft column on the RDP is there not for planning but rather just in case a diver accidentally dips down a few more feet and needs to calculate pressure groups after the fact. I teach Deep Diving specialty and have never encountered any mention of 140 feet as a recommended maximum depth, so I simply wondered if CompuDude (or another reader) could point me to a source that I could consult for this recommendation. So far, the only sources mentioned by anybody seem to have been oral discussions during classes and the notation on the RDP/RDP booklet clearly stating: 42 meters is for emergency purposes only, do not dive to this depth.


Nope, you are correct, and I believe CD was maybe just miswording what he meant...

OW - 60 ft / 18m
AOW - 100 ft / 30m
Deep Specialty - 130 ft / 40m (which is really 132 ft)
Contingency - 140 ft / 42m (only if you accidentally went that extra foot or two and had to recalculate your pressure group during / after a dive...

It's kinda like PO2 planning - we plan for 1.4 (recreational sense), but have charts for 1.6 just in case...

CompuDude
08-20-2009, 15:15
Nope, you are correct, and I believe CD was maybe just miswording what he meant...

OW - 60 ft / 18m
AOW - 100 ft / 30m
Deep Specialty - 130 ft / 40m (which is really 132 ft)
Contingency - 140 ft / 42m (only if you accidentally went that extra foot or two and had to recalculate your pressure group during / after a dive...

It's kinda like PO2 planning - we plan for 1.4 (recreational sense), but have charts for 1.6 just in case...

Well, I don't think I've misworded anything, but apparently people are reading more into "emergency contingency" than was intended. The "limit" is 130'/40m... as I said. For emergencies, well, I guess everyone has to use their own judgment, but PADI provides information to assist with a dive that happens to hit 140', on purpose or otherwise.

Considering you're supposed to have the Deep Specialty to hit the 130' limit, I'd think it's pretty implicit that you should have that (at least) if you're going beyond the limit, as well (advisable or not).

Jack Hammer
08-20-2009, 15:19
Most wrecks tend to be in a least 40-60', if not considerably deeper.
A lot of wrecks in shallower water tend to get dynamited to remove navigation hazards.
Not to mention the shallower wrecks tend to get picked clean over the years by rec divers wanting souvenirs. The effects of this have been especially noticeable in my local waters.

CompuDude
08-20-2009, 15:59
Most wrecks tend to be in a least 40-60', if not considerably deeper.
A lot of wrecks in shallower water tend to get dynamited to remove navigation hazards.
Not to mention the shallower wrecks tend to get picked clean over the years by rec divers wanting souvenirs. The effects of this have been especially noticeable in my local waters.

And then there are wrecks like the Liberty Wreck in Bali, which starts at 30' and goes down to 100' or so. Fantastic wreck, readily accessible, and a very short swim from shore.

Scuba Pete
08-20-2009, 17:46
Nope, you are correct, and I believe CD was maybe just miswording what he meant...

OW - 60 ft / 18m
AOW - 100 ft / 30m
Deep Specialty - 130 ft / 40m (which is really 132 ft)
Contingency - 140 ft / 42m (only if you accidentally went that extra foot or two and had to recalculate your pressure group during / after a dive...

It's kinda like PO2 planning - we plan for 1.4 (recreational sense), but have charts for 1.6 just in case...

Well, I don't think I've misworded anything, but apparently people are reading more into "emergency contingency" than was intended. The "limit" is 130'/40m... as I said. For emergencies, well, I guess everyone has to use their own judgment, but PADI provides information to assist with a dive that happens to hit 140', on purpose or otherwise.

Considering you're supposed to have the Deep Specialty to hit the 130' limit, I'd think it's pretty implicit that you should have that (at least) if you're going beyond the limit, as well (advisable or not).

I got it. Not that is saying anything.

Man is it beautiful outside. Sunny mid 70's with a breeze. Perfect.