100' vs 130'??

[El Diablo]

Another thing is that most people diving deeper than 30m are on air not always on Nitrox with max 34m depth.

Do watch your NDL at depth.... I went to 38m on air to get video of these red toothed trigger fish. The dive outfit I was with prefer divers to have 4 or 5 minutes NDL so they do not accidently go past that into deco. You can see in my video I pay attention to my NDL.

I believe you should be able to set a NDL audible alarm in most good new dive computers. My wife just got an 'entry level' and newly announced Aqualung i330r and I was surprised it has it... that little thing is sending all manufacturers back to the drawing board. Great colored screen at a great price

 

[Blackcrusader]

I believe you should be able to set a NDL audible alarm in most good new dive computers. My wife just got an 'entry level' and newly announced Aqualung i330r and I was surprised it has it... that little thing is sending all manufacturers back to the drawing board. Great colored screen at a great price

My Shearwater Perdix does not have audio alarms. That is what I like about it. You pay attention not waiting for some alarm that you may hear or not.

 

[OnTheMark]

Another thing is that most people diving deeper than 30m are on air not always on Nitrox with max 34m depth.

Do watch your NDL at depth.... I went to 38m on air to get video of these red toothed trigger fish. The dive outfit I was with prefer divers to have 4 or 5 minutes NDL so they do not accidently go past that into deco. You can see in my video I pay attention to my NDL.

Nice video

 

[chillyinCanada]

and that is their right to do so. pretty silly though. many very experienced divers have no formal training beyond the ow level.

i would repeat my comment to john above....imho they should have simply assessed the skill level first, and then make the decision on whether to limit their depths or not. but perhaps it is some type of insurance requirment ?

I suspect that the LOB already knew the divers' experience, and to confirm that they'd been observed during the shakeout dive.

There's at *least* one Caribbean dive locale with which I'm very familiar and going on dives below 60' are an absolute no go without AOW certification or equivalent, any experience aside.

Now, having said that, I had had mine for years and a couple hundred dives or more before I ever turned up at that locale, so it was never me that wasn't allowed to go on special dives. I saw quite a few others turned down.

On top of that, when I first turned up, I was unencumbered above 130' and we even did a few dives planned to that depth. On a return trip to that certain site, I was frustrated to find that looking over the edge at 130' was not to be "done" anymore.

But I kept my frustration to myself because there were other newer divers aboard and hey, the locales' boat, their pool, their rules.

 

[Wibble]

I believe you should be able to set a NDL audible alarm in most good new dive computers. My wife just got an 'entry level' and newly announced Aqualung i330r and I was surprised it has it... that little thing is sending all manufacturers back to the drawing board. Great colored screen at a great price

Not at all. The useless lump of Suunto crap beeps incessantly. It's ignored.

You're supposed to pay attention to your gas volumes, your depth and your NDL/TTS. Your life depends upon that.

 

[Centrals]

Not at all. The useless lump of Suunto crap beeps incessantly. It's ignored.

You're supposed to pay attention to your gas volumes, your depth and your NDL/TTS. Your life depends upon that.

Nothing wrong with the alarm. It is a good idea for many divers.
It can be dis-armed if required in most if not all models. However, I had came across some divers who did not understand why the alarm came off and did nothing or did not know what was happening. Many of them never completely understood the function of his/her own dc.

 

[Centrals]

Again; YOU are responsible for monitoring your gas, your depth and your NDL/TTS. More safety nets means less focus on continual monitoring.

This is "New divers or those considering diving" sub-forum.
Therefore should be more considerate for them. And this is a recreational sport after all.

 

[Wibble]

We'll have to agree to differ.

I like things simple, 'cos I'm stupid, especially when underwater.

When diving one needs ones wits about oneself. In the beginning you must make sure you concentrate on monitoring your kit and equipment until it's automatic. Agreed, as a novice, you're in relatively benign conditions, but don't let that lure you into a false sense of security; you cannot breathe water.

Continual monitoring of your gas, depth and NDL has to be done by yourself. You cannot delegate that to something else, like an alarm that may or may not go off. You cannot be so distracted as to ignore your monitoring obligations.

What was old story about the boy who cried wolf?

 

[boulderjohn]

SSI & PADI are limited to 30m, CMAS & I believe NAUI (not sure about the last) 40m.

I assume you did not read the posts that explained things correctly before you posted this. Here is a quick summary for those who also skipped the informative posts.

1. Required limits are for instructional dives only.
2. PADI and SSI have instructional limits down to 40m for the appropriate dive classes
3. No agency has any authority to limit your depths when you are diving outside of instruction.
4. Local dive operations and governments have the authority to set diving limits.
5. The supposed limits of PADI and and SSI (and all others) are recommendations to guide divers as they gain experience. PADI and SSI recommendations extend to 40m.
6. Nearly all agencies limit recreational dive depths to 40m. After that, mandatory decompression stops are involved with most algorithms.

 

[drrich2]

Is this just to maintain a safety buffer or is there some other knowledge to be had diving between 100' and 130' or is this just another way for the agencies to sell another specialty course?

Apologies if this has been covered; I've been skimming the topic the past few days. Others have pointed out you run a substantially escalating risk of performance impairing nitrogen narcosis going deeper. This is a serious enough issue to be worth expanding on.

1.) You may not realize you're impaired. Occasionally someone posts a 'funny' story where a dive buddy does something odd and doesn't recall it after the (deep) dive. Or someone seems to be wondering around apathetic and progressively low on gas. Being seized with an anxiety attack that resolves with maybe a 15 foot ascent, perhaps.

2.) The nature of narcosis effects varies. Whether you're just slow, functionally 'dumb' or dangerously indifferent or unperceptive, have narrowed awareness or an anxiety attack...if you don't realize it (or how bad it is) and you're rapidly running out of gas and NDL time (and likely haven't been trained to deal with deco obligations, even if you have the gas left to meet them)...well, things could 'go south.'

3.) Narcosis effects aren't consistent person-to-person. Some people are unusually susceptible, some more resistant. Just because most people are fine with a dive is no guarantee you will be.

4.) Narcosis effects aren't consistent over time in the same person. I remember one of our seasoned members, @drbill describing different experiences when he'd been diving regularly vs. when it'd been awhile. As a result, I prefer to avoid diving very deep my first day or two on a trip (especially if diving solo), and I don't go over 100-feet solo without a pretty good motivation.

5.) Depth and duration aren't the only factors in play. Others already discussed that.

I also got dark narked bad on that wreck. I did it on a HP80 slinging an AL30 with a buddy who wandered a bit. I got down to 117ft when we dropped off the stern to see the huge twin props. It was dark and bad viz.