Bent in Cozumel

[diverincanada]

Matt, (and Tim)

I don't think Tim did anything wrong here. It's just that when we dive air to the limits of the dive computer algorithm, we take a chance. Most of us luck out most of the time. Unfortunately, Tim had to suffer so we could be reminded that it can happen. I hope you are well Tim.

My two cents is - Nitrox and more Nitrox!

If you are on Nitrox and everyone else is diving air, you will have the same dive, same profile but it gives you back your margin of safety.

I just got back from Cozumel too and dove Nitrox.

Here is a tip. Any dive shop in Cozumel can get you Nitrox (central fill station) but they don't all have Oxygen testers. So, If you don't have your own, make sure you call ahead before you book with the dive operator.

CG

Tim, (or anyone),

What do we do different short of going easy on the alcohol the night before? I have a VEO 200 as well, and am going to Cozumel May 1 thru the 9th. I'm assuming you used Aldora's larger tanks with air? We'll probably be using aluminum 80's. I'd really like to hear suggestions from all of you vetrans out there as I don't care to go through what Tim did, but still want to do long deep SAFE dives. I hope all is well with you Tim.

Thanks in advance,
Matt

 

[Tim Ingersoll]

Thanks for asking. I am at about 99% recovery at this time. A little residual weakness and a tiny bit of a twinge of pain every once in a while. Really wish I could get back on the horse again.

 

[5615mike]

Matt, (and Tim)

I don't think Tim did anything wrong here. It's just that when we dive air to the limits of the dive computer algorithm, we take a chance. Most of us luck out most of the time. Unfortunately, Tim had to suffer so we could be reminded that it can happen. I hope you are well Tim.

My two cents is - Nitrox and more Nitrox!

If you are on Nitrox and everyone else is diving air, you will have the same dive, same profile but it gives you back your margin of safety.

I just got back from Cozumel too and dove Nitrox.

Here is a tip. Any dive shop in Cozumel can get you Nitrox (central fill station) but they don't all have Oxygen testers. So, If you don't have your own, make sure you call ahead before you book with the dive operator.

CG

Nice Point but personally, I don't trust any analyzer that I don't know has been calibrated. If your using the same analyzer they used, obviously your going to get the same possible incorrect reading. Invest your money in a good analyzer if your going to dive EANx.

 

[Charlie99]

Nice Point but personally, I don't trust any analyzer that I don't know has been calibrated. If your using the same analyzer they used, obviously your going to get the same possible incorrect reading. Invest your money in a good analyzer if your going to dive EANx.

I like the system at most Cozumel dive operators better than what I typically see at US dive shops. At a lot of US dive shops, the analyzer used to test the gas when you pick it up might very well be the same one that they used to check things when they first filled it.

In Cozumel, most dive ops use an independent nitrox supplier. That supplier puts on each tank little stick-on labels with the O2% that look like they have been printed by an O2 analyzer. Then you test the gas again, using the dive ops analyzer (which you can check for cal at 21%). If the label from the outside nitrox supplier and the dive op's analyzer more or less agree, then I'm pretty confident about the mix.

If you review accidents related to nitrox, you will find that they are caused by gross errors, not by being off a percent or two. Using 2 different analyzers is a good safety practice.

Charlie

 

[diverincanada]

Agreed,

Nothing beats having your own tester. But if you don't have one, the tester on the boat is probably just fine since you calibrate it every time you use it anyway.

In Cozumel, the central nitrox fill station is fairly slick. All of the tanks I used from the central fill 'appeared' to have been tested twice (probably once after the fill then again after it cooled). There were two test stickers on each tank bearing a test result. Then I tested the tank myself with the tester on the boat and was within a half a percent - good enough for me.

The only problem in Cozumel is that not all of the boats (or dive operations have a tester) - even very well known operations like Papa Hogs, don't have a tester - not on any of their boats or in their shop. I mention Papa Hogs since they are Ex-Pats from Canada and I had hoped for better service from them. It turns out they are not service oriented at all (tried them on two separate trips to Coz and was dissapointed each time and finally gave up on them and moved on to a new operator).

If you are diving Nitrox in Cozumel, bring your own tester or call ahead to make sure your dive op has one for you.

C

 

[Texas Diver]

Last month on Cozumel my wife and I got Nitrox certifiied through Blue XT Sea. As part of our course work we visited the central fill station. The shift manager gave us a tour of the facility and showed us how they mixed Nitrox gas and how they measured the finished product. I was impressed with the process and controls. Although the experience gave me comfort about how the gas is mixed and measured, I would still not use their nitrox mix without testing it myself with an instrument I trusted.

As an aside: I've heard the family that owns the fill station is worth millions! They own the yacht parked inside its own pier on the waterfront. I heard the government gave them the fill station rights and will not let anyone compete against them. Nice business model - high margins; high volume; no competition; govt protection = la dolce vita! It is the perfect business to own. You can mismanage the hell out of it and still make a fortune! These guys make money every time they breathe, or more accurately, every time we breathe!

 

[Water Bear]

@ Tim thanks for the lessons on life...if we can't learn from other people's life experiences (notice I didn't say mistakes)..., then we are just :fruit:

 

[Cassie]

Just want to thank you for the information. I am newly certified and I feel that your collective experience will make me a more aware diver. Also my husband and I just joined DAN.

 

[Tim Ingersoll]

I can't tell you how good that makes me feel.

 

[Foo]

Okay, please understand that I am a newbie diver, just certified Open Water in Jan., with about 15 dives so far. I've read this entire thread with fascination, and it does show me just how much I DON'T know about diving. Also, please understand that I'm asking this question in ignorance, and am not trying to be a smarta$$, okay? I just want to learn.

I don't have a dive computer yet. So, I looked at the dive tables that we learned to use, in my cert class. On their first dive, Tim said they went to about 100 ft, then most the dive was between 60-80 ft, if I'm not mistaken. On the first dive, then, according to the table, they should not have been diving beyond 55 minutes, even if they only went to 60 ft, which they did go deeper, right? Or am I not reading this table correctly? (It is the NAUI table, if that makes a difference). Again, I'm not trying to be offensive, or say someone did something wrong- I'm just not sure why the dive ops took them that deep for so long? I'm going to Coz at the end of June, we'll have several certified teens with us (my daughter included) and I don't want to have a similar story to report when we return home. Or is this just a more advanced type dive that I know nothing about? Thanks for any help you can give!
Foo