Nitrox

[Christi]

Don't ever dive EANx without testing with your own rig IMO. You don't know how or when the last one was calibrated or if it even works properly

My last trip to Coz in May I did 12 dives on EANx and 4 on air. Of those 12 tanks, only one tank was w/in 3 points of labeled mix. When your approaching MOD that gets dicey. Had to dive air at Punta Sur b/c the tank they had for me marked 32 was 36 and the 36 for second dive was 38.

I'm not at all disagreeing with the fact that you should analyze your own tank. That is a given!

However, your other statement is interesting. Like I have said before, there is only one fill station that fills nitrox here. These guys are well trained and in fact do know what they are doing.

There SHOULD be TWO stickers on the tank. The mixer analyzes the tank when he fills it, then it is analyzed again after the tank cools. I have only experienced two incorrect markings (not within 1%) in the last 3 years.

Is it possible that the analyzer you were using was not properly calibrated?

 

[HammerNoMore]

Anyway Christi,

To get back to my original point, before the soapbox got started up. I went back and checked, my average dive 1 in Coz is around 80 feet if you ignore the Southernmost and Northernmost dive sites. 80 feet is IMHO a perfect depth for EAN. For the second dives it's really wasted.

Like I said, if you want to do the more advanced sites, you shouldn't just hop on a boat and assume you can go there. You should plan that in advance with the shop so they can pair you up with other experienced divers. Can you exceed 100 feet on the "walls"? Yea, sure, but there is no need to. Why not just allow divers to get one bottle a day and let them (within your defined safety limits) decide if they want to use it on the first or the second dive.

If the boat goes to the far south, they can use it on the second. If they go to Panacar Gardens, they have the option to use it on the first dive?

James

 

[Christi]

Anyway Christi,

To get back to my original point, before the soapbox got started up. I went back and checked, my average dive 1 in Coz is around 80 feet if you ignore the Southernmost and Northernmost dive sites. 80 feet is IMHO a perfect depth for EAN. For the second dives it's really wasted.

Like I said, if you want to do the more advanced sites, you shouldn't just hop on a boat and assume you can go there. You should plan that in advance with the shop so they can pair you up with other experienced divers. Can you exceed 100 feet on the "walls"? Yea, sure, but there is no need to. Why not just allow divers to get one bottle a day and let them (within your defined safety limits) decide if they want to use it on the first or the second dive.

If the boat goes to the far south, they can use it on the second. If they go to Panacar Gardens, they have the option to use it on the first dive?

James

You are absolutely correct. 80 ft is a perfect depth to take advantage of the EAN, and most of our first dives do range between 80 and 100. Actually, I usually do exactly what you suggested with regads to the nitrox. They can use it for the first dive if appropriate, or for the second dive. However, I disagree that it is wasted on the second dive. In my opinion, EAN is never wasted...of course that is MY opinion.

I also agree that the advanced sites need to be planned in advance, which we typically do. However, when we have a group we know well and know their qualifications, we can decide on a whim to head out to Maracaibo if conditions are favorable.

 

[alcina]

Well, after digging through the little snit-fits I found most of the info helpful, if a little off topic. Christi - thanks again for your excellent advice and comments...it is clear to see why you are considered one of the best and I look forward to meeting you & diving with you (must remember to get your street address!)

I will bring our analyser in case there isn't one on the boat (which shouldn't happen, but they can get dropped overboard etc!). I would never, and would never recommend, diving on a tank not personally tested by the diver.

80 - 100 feet; max roughly 33m works for me. Looks like most are multilevel dives anyway. DH will only be diving air mostly, I think.

Organize Nitrox ahead of time - check!

Back to a little off-topic. I know we all know what we are talking about when you have been discussing "nitrox" - 32% & 36% for the most part. But for others who may not know anything or enough about Nitrox, there are other mixes available for a range of depths beyond 100' (Christi did touch on this in her last post re the Throat). These dives & plans may or may not be beyond the realm of the "average Coz recreational" diver. I find there are several sites here where 28-29% is perfect and beneficial.

Anyway, thanks for the info and taking the time to respond...appreciated.

 

[HammerNoMore]

Actually, I usually do exactly what you suggested with regads to the nitrox. They can use it for the first dive if appropriate, or for the second dive.

Good to hear. In the original post it sounded like you didn't allow EAN on the first dive.

However, I disagree that it is wasted on the second dive. In my opinion, EAN is never wasted...of course that is MY opinion.

Let me explain a little. $10 a tank is not that big a deal, but I have a baby due in October, so I'm about to leave DINKdom. I've calculated that the childcare alone is going to run us $900 a month, ouch! My last trip to Coz cost about $700 in airfare, dives and hotel. Had I done EAN for every dive that would have been and extra $100, a big percentage. When I say wasted, I mean that it's not really extending your time underwater. I definatly am in the group that feels better on nitrox, but I can take a little fatigue if it means an additional Coz trip down the road.

P.S. alicina, I apologize for derailing the thread. I just don't like being misquoted in a way that makes me look like I'm recomending unsafe practices.


James

 

[Wristshot]

Alcina,

At the risk of putting the thread back on track. . . .

I dove with Deep Blue last month. They bring an Ox Analyzer on the boat when they have Nitrox. They only use 36% to keep things simple. They said that they could get custom mixes, but it costs extra and it is just not worth it in their opinion. They charge and extra $10 for Nitrox (I think it was 10).

A lot of the Guides and DMs use Nitrox on their second dives.


Wristshot

PS: every tank that I saw people check was within .2 of 36%.

 

[Christi]

Well, after digging through the little snit-fits I found most of the info helpful, if a little off topic. Christi - thanks again for your excellent advice and comments...it is clear to see why you are considered one of the best and I look forward to meeting you & diving with you (must remember to get your street address!)

I will bring our analyser in case there isn't one on the boat (which shouldn't happen, but they can get dropped overboard etc!). I would never, and would never recommend, diving on a tank not personally tested by the diver.

80 - 100 feet; max roughly 33m works for me. Looks like most are multilevel dives anyway. DH will only be diving air mostly, I think.

Organize Nitrox ahead of time - check!

Back to a little off-topic. I know we all know what we are talking about when you have been discussing "nitrox" - 32% & 36% for the most part. But for others who may not know anything or enough about Nitrox, there are other mixes available for a range of depths beyond 100' (Christi did touch on this in her last post re the Throat). These dives & plans may or may not be beyond the realm of the "average Coz recreational" diver. I find there are several sites here where 28-29% is perfect and beneficial.

Anyway, thanks for the info and taking the time to respond...appreciated.

You are correct that 28% - 29% would be ok for certain dives here as well. However those would be considered special mixes, and more expensive than the standard 32% or 36%, and like Wristshot said, really not worth it.

GENERALLY speaking, most people who use nitrox here are diving it because they are diving multiple dives over multiple days and are simply using it for the added safety factor (which I am aware is debatable). Not too many people actually use it here to extend bottom time. We are fortunate here that almost every dive can be a nice multi-level dive which obviously helps maximize bottom time safely.

Alcina, I would love to meet you as well, and thank you for the nice comments Please keep in mind if you want to book any dives with us, that I stay pretty booked up and I do require reservations. I do not have a shop with normal shop hours open to the public, but you are welcome to call while you are here and I can give you the address if you want to stop by while I am here. The nature of my operation keeps me out of the office several hours a day tending to the boats and customers, so always best to call first.

Let me explain a little. $10 a tank is not that big a deal, but I have a baby due in October, so I'm about to leave DINKdom. I've calculated that the childcare alone is going to run us $900 a month, ouch! My last trip to Coz cost about $700 in airfare, dives and hotel. Had I done EAN for every dive that would have been and extra $100, a big percentage. When I say wasted, I mean that it's not really extending your time underwater. I definatly am in the group that feels better on nitrox, but I can take a little fatigue if it means an additional Coz trip down the road.

I see your point and I agree. Congratulations on your new baby and you made me laugh with your "DINKdom" comment I hope you'll still be able to make a few dive trips a year!

Anyway, I'm signing off for the night...been at the computer ALL day today!

Have a good night everyone! It's been fun and glad we all had a little nitrox course today...

 

[HammerNoMore]

I see your point and I agree. Congratulations on your new baby and you made me laugh with your "DINKdom" comment

I hope you'll still be able to make a few dive trips a year!

Anyway, I'm signing off for the night...been at the computer ALL day today!

Have a good night everyone! It's been fun

and glad we all had a little nitrox course today...

Glad I gave you a laugh, I know they are so hard to come by down in paradise [big smiley]. I was also wondering how you had the time to post all day...seeing as you have a business to run [little smiley] Good night...

James

P.S. Sorry about the simely comments. Seems I found a small bug in SB that wouldn't let me quote Christi with 3 smiley images and add two of my own...

 

[Christi]

Glad I gave you a laugh, I know they are so hard to come by down in paradise [big smiley]. I was also wondering how you had the time to post all day...seeing as you have a business to run [little smiley] Good night...

James

P.S. Sorry about the simely comments. Seems I found a small bug in SB that wouldn't let me quote Christi with 3 smiley images and add two of my own...

James,
I was posting in between catching up on e-mails. Everytime someone replies to this post, I get an e-mail notification...but, reality is I am confined to the office at the mercy of the Mexican postal service this week. I am waiting for a very important document regarding my business that ONLY I can sign for. If I'm not here, it gets sent back to Mexico City and the process starts all over again. After trying to get this thing delivered (official change of business address, that I need proof of for several things) for close to a year, I am not leaving this office until it is delivered, and they SWORE it would be delivered this week! Hopefully today will be my last "hurry up and wait" day