Maximum depth for Open Water diver

[Web Monkey]

As soon as I wrote down a number, I knew somebody was going to pop up and say "I've been to xxx feet."

130' is the NDL for SSI. I beleive PADI is 140', and the bottom times are very short.

If they make you happy, feel free.

Terry

I've been to 140 without deco obligation & dove with a diver who went to 150 with no deco obligation (both planned no-deco dives). My tables say if I start clean, I can go to at least 160 with no deco obligation. Times at depth are, of course, somewhat short.

Terry

 

[redacted]

As soon as I wrote down a number, I knew somebody was going to pop up and say "I've been to xxx feet."

130' is the NDL for SSI. I beleive PADI is 140', and the bottom times are very short.

If they make you happy, feel free.

Terry



Terry

I just wanted to make sure we didn't let myth replace the physics/science here.

 

[HowardE]

The point of PADI and other orgs is to make it SAFE for MOST divers. You wouldn't have to have a deco obligation if you venture past 130' on air for a few seconds...PADI's dive tables are conservative, in an effort to make recreational diving just that. It's not about diving "on the edge". Of course there are those that have to go deeper for longer, and push the limits. Knock youself out (literally). Go for it. It seems to me that the person who started this thread had a simple question.

Personally, my first OW dive was to 70'... The advice to the starter of the thread. Dive within your limits, both personal, and the limits you see on your RDP, and you will be a safe diver.

 

[Web Monkey]

This "Diving on the edge" stuff makes me crazy. Nobody gets bent or killed, until they do. Then it's too late.

It's like OxTox. I love it when I look in the Nitrox log book and see that someone has a deep dive planned, so they change their PO2, instead of their mix, so they get an MOD that works for the dive. It's like they think that biology and physics cared about their "Fun with math" exercise.

Terry

The point of PADI and other orgs is to make it SAFE for MOST divers. You wouldn't have to have a deco obligation if you venture past 130' on air for a few seconds...PADI's dive tables are conservative, in an effort to make recreational diving just that. It's not about diving "on the edge". Of course there are those that have to go deeper for longer, and push the limits. Knock youself out (literally). Go for it. It seems to me that the person who started this thread had a simple question.

Personally, my first OW dive was to 70'... The advice to the starter of the thread. Dive within your limits, both personal, and the limits you see on your RDP, and you will be a safe diver.

 

[david.tolan]

Depth is only one factor.

Any halfwit can get to 30 meters and back up with a modicum of luck in clear blue warm water with no current and an anchor line to go up and down. (Been there, done that)

Throw in a current, cold, crap vis, darkness at depth, and unfamiliar equipment, the same halfwit would be lucky not to end up in a chamber. (Trust me on this)

Ps. Some dive insurance is void if you dive beyone your rated depth, and some operators won't take you deeper than you're certified for.


---- You start out diving with a little bit of luck and no experience.
It's vitally important to build up that experience without running out of luck. ----

 

[redacted]

This "Diving on the edge" stuff makes me crazy. Nobody gets bent or killed, until they do. Then it's too late.
Terry

There are "edges" at lots of depths. What is closer to "the edge"? 70 ft for 40 minutes or 150 ft for 5 minutes?

 

[HowardE]

This "Diving on the edge" stuff makes me crazy. Nobody gets bent or killed, until they do. Then it's too late.

Absolutely... It's just like saying, "I don't wear my seatbelt when I drive, since I've never been in an accident before"

 

[Web Monkey]

There are "edges" at lots of depths. What is closer to "the edge"? 70 ft for 40 minutes or 150 ft for 5 minutes?

Since 70' for 40 minutes is on both of my tables and 150' isn't on either, I'd say that 150' is over the edge.

What do I win?

Terry

 

[redacted]

Since 70' for 40 minutes is on both of my tables and 150' isn't on either, I'd say that 150' is over the edge.

What do I win?

Terry

My table puts 70/40 as the NDL - 70/41 is deco. But for 150, 10 minutes is the NDL. So if the edge is based only on NDL, I'd put 70/40 on the edge but have a 5 minute cushion with 150/5. Of course, there are probably other edges that should also be considered. Like experience, comfort, and ability to deal with narcosis.

To each his own I guess.

 

[Iruka]

As soon as I wrote down a number, I knew somebody was going to pop up and say "I've been to xxx feet."

130' is the NDL for SSI. I beleive PADI is 140', and the bottom times are very short.

If they make you happy, feel free.

Terry



Terry

To clarify, for PADI as well the recommended recreational limit is 130' or 40 Meters (which is actually about 132' when converted. So I guess if someone "breaks" 130' by a foot or two, just log it in as metric and you'd survive, ha ha.

The rest of this are just my thoughts on the depth limits....not directed at anything you (Terry) said:

I think "recommended max depth for new divers" is often translated as "max depth forever until you pay for another course." With most new divers, it IS a good idea to stay fairly shallow until they get comfortable with diving. When I have divers making their first deep dive, I can tell them what they'll need to know to do that dive safely with me, under the conditions on that day. The main things to consider are 1) your air consumption will of course increase 2) you have to pay attention to time....at 10m 33', you can basically stay down for hours if you have air and 3) you have to pay attention to depth....dropping from 30' to 60' won't create any narcosis risk, for example, but that same 30' "drop" from a "deep" dive might cause significant narcosis. And even deeper, you'll have oxygen toxicity issues to deal with (as a recreational diver on air, you don't have to consider them at rec. depths.) When I'm guiding/teaching, I'd PREFER that the diver keep those 3 points in mind during the dive.....but I explain that I WILL be watching time, depth & air consumption.....so my only real concern is the diver's comfort level...if they're not going to panic at the THOUGHT of diving a little deeper, they'll be fine. Even when we have a deep dive "planned" I always tell them we'll "re-evaluate" at around 15 to 20 meters (50~70' roughly)....we have a prearranged "are you ok going deeper?" hand signal...anybody doesn't want to go deep, and we don't go, no problem. (I don't get paid by the foot, ha ha). In some cases, I'll decide on the initial descent that today we will NOT be going deep....if the divers are obviously having problems with the descent, I'll decide to make the dive as easy as it needs to be.

I won't take any customers below the rec. limit (mostly because of liability issues) but I feel I can give enough training (no extra charge) to make a safe SUPERVISED recreational dive without requiring the diver to take an AOW or Deep course. Extra courses are fine, but in some cases I think competent divers are "held hostage" to a degree by being forced to take a course before they can do certain dives. (for example, a shop I used to work for wouldn't allow night dives unless people took an advanced course....even if they had hundreds of dives already...and these were very easy, unchallenging beach night dives.) This wouldn't apply, of course to cave or wreck penetration dives where specific training would be needed, I'd think, to make the dives safely.