31 replies to this topic

[Geek]

However, he plainly stated during the introductions that he didn't believe in Nitrox and probably wouldn't ever use it. Now I'm all for taking specialities for the heck of it, I may take the UW photography just to see if I like it. However, it struck me as odd that he would go through this non-diving dive training if he didn't plan to use it.

My take on this is he needed to take the course more than any of the rest of you because he he had no idea what he was talking about.

Air is 21% nitrox.

[Diverbrian]

It drives me nuts to pay good money to diving and then have my dive cut short by a lack of bottom time available due to a leaner mix that I have to dive.

It drives me nuts to pay extra for nitrox when it won't increase my bottom time at all.

At 50 ft on EAN 40, my NDL is unlimited, on air my NDL is 1 hour 20 minutes.

At 40 ft on EAN 40, my NDL is unlimited, on air my NDL is 2 hours 30 minutes.

At 30 ft (or shallower) on EAN 40, my NDL is unlimited, on air my NDL is unlimited.

Why would you pay extra for nitrox on shallow dives?

I also dive air on walls. Unless there's a hard bottom, I don't dive nitrox. I plan my mix for the hard bottom or I pass on nitrox.

In the case of shallow dives, it is that much less nitrogen that I am picking up in case something were to happen and I had to go to the surface. My tendency is EAN 36 on these dives. At the price of $10.00 a fill vs. $6.00 a fill for straight air, the cost difference isn't that significant. To be honest, I see your point at thirty feet or above, but there are other factors. Normally, those are the last dives that I do for the day and I am just using the remainder of my breathing gas from the day's diving on deeper dives. There just aren't many entertaining 20-30 ft. beach dives up here.

If this is not the case, keep in mind the other type of the shallow dives that I do anymore. They normally involve students. I have had more than one student feel the first blast of cold water in their mask and try to find a new home on the surface. Meanwhile someone has to go up and verify that they are all right. Especially with our normal idea of good vis. being about 20 ft., you have to stay near your dive buddy or the students. I was very happy that the shop fired the one instructor (owner's son) who was most notorious for rushing students through training for the reason of all of the problems that seemed to occur during the in-water portion of his classes. In any case, with all of this going on, the less nitrogen in that breathing mix, the better that I feel.

Oh, and we both know people who can easily do that 50 ft. dive for better than an hour and half on an Al80. I would swear that the people in Florida are issued bird lungs as standard course. My RMV during classes is in the low .4 range and one member of this board is notorious for her RMV of .3 cubic ft/min. Throw in a repetitive dive and the EANx mixtures come into their own.

When I was diving walls in Provo, I dove nitrox. The hard bottom on those walls is four to six thousand ft. That is a good example of requiring good buoyancy control, planning your dive and diving your plan. I am not going deeper than 130 in any case due to the possibility of being narced out of my brain.

I actually had a dive shop owner give me a lecture because my mix was too lean for his taste. His arguement was if I needed EAN28, I actually needed helium in my mix or not be going that deep. He partial pressures, but will ONLY fill EAN32 or EAN36 (or Helium mixes). I don't think that I saw air as an option for fills at his shop either. I got irritated enough with him (I am trained for nitrox mixtures down to 135 ft.), that I told him that I was paying for a tank fill and not a lecture. I won't add what else I said. I would have to delete too many expletives. One of the books that his training agency (which I don't take training from for many other reasons) publishes has a small section where the author basically points to diving air for anything as an archaic practice with the more preferred mixes out there. I bring this point up to emphasize that I am far from the most narrow minded individual out out there on diving straight air. I don't criticize someone for diving straight air. I just don't like to do it for myself.

On and yes (to the person who asked), on deep dives you are relying on a rich EANx to do your decompression in staged decompression diving (I don't wish to specify too much here. I want to encourage people who wish to do this to get actual training and not just read it off of the internet.) . Decompression on the whatever mixture that you are diving at depth would take far too long for my taste.

[Trimix2dive]

To answer the original poster. Your comedic friend is a bonehead. Various Nitrox mixes are the deco gas for tech divers. Nitrox has an extreme added value in recreational diving.

It sounds like that he may have gone diving with his tanks filled with Xenon (xenonox) a few to many times.

Oh, and I fill my tires with helium. It makes by car lighter and increases my fuel economy. Now my tires make a high pitched squeeky sound when they roll too.

[Walter]

Now my tires make a high pitched squeeky sound when they roll too.

LOL!

[intotheblue]

WOW! I missed alot... Trimix has it's advantages too, but I'm not as dogmatic as many I know about adding Helium to EVERY tank for every dive. I understand the benefits, but as with everything... you employ the "cost-benefits analysis" and must decide accordingly. I don't do DEEP dives on air or Nitrox any more, but I often use air for medium and shallow range dives, but follow with a stage bottle for deco at 20 feet to flush some of the N2 out of the system. I have acquaintences that feel about Trimix the way it was expressed about Nitrox... using it in their tires. Personally, I use Argon!

Oh, and to see why we justify using Helium in breathing gas... read "The Last Dive" if you haven't. If I ever thought about diving DEEP on anything but trimix, that removed any trace of that thought. Of course, now we have to define "DEEP"!

And... any reference that was made by me about trimix or "deco" gases in earlier posts were directed towards the "trimix" wannabe that saw no use for "nitrox". Once diving Trimix, the importance of "nitrox" or Oxygen will become much more apparent to him. For those diving recreationally, don't be enticed into doing things to complicate your diving. Anyone that is familiar with my posts knows I stress getting lots of experience and training before taking up forms of tech diving, incl. cave diving. Breathing the gas is the easy part... what to do when you lose bouyancy, lose gas, have a reg. or guage malfunction, etc... those are the real things a tech diver needs to know and train for. Also, deco on a Trimix dive is different than on a nitrox dive...

[Trimix2dive]

Is this nitrox student must be the same guy that wanted to know if, a spare air could be nitrox converted to use as a back up redundancy to his 80/20 stage bottle? :lam:

[dustbowl diver]

I have acquaintences that feel about Trimix the way it was expressed about Nitrox... using it in their tires. Personally, I use Argon!

I don't anything about using mixed gas in your tires, but Argon works great at improving the thermal performance of the windows in your house!!!

DBD

[scubafanatic]

It drives me nuts to pay good money to diving and then have my dive cut short by a lack of bottom time available due to a leaner mix that I have to dive.

It drives me nuts to pay extra for nitrox when it won't increase my bottom time at all.

At 50 ft on EAN 40, my NDL is unlimited, on air my NDL is 1 hour 20 minutes.

At 40 ft on EAN 40, my NDL is unlimited, on air my NDL is 2 hours 30 minutes.

At 30 ft (or shallower) on EAN 40, my NDL is unlimited, on air my NDL is unlimited.

Why would you pay extra for nitrox on shallow dives?

I also dive air on walls. Unless there's a hard bottom, I don't dive nitrox. I plan my mix for the hard bottom or I pass on nitrox.

Hi Walter,

...could you clarify for me your logic here? If you use a PPO2 of 1.4 ATA on air , your MOD is 187 ft. If you used EAN 32, your MOD @ 1.4 ATA PPO2 is 111 ft.

...... it appears to me, that if you'd dove the walls of Turks & Caicos ( as I just did during my 27 dives 2 weeks ago on the EXPLORER) with hard bottoms ranging down to 6000 ft. , and something went wrong, with a 6000 ft. 'hard bottom' you'd be pretty much be just as screwed diving 'air' as EAN32, a 76 ft. differential doesn't seem to make a material difference when viewed against a 6000 ft. deep backdrop.

.......gotta warn ya, the Flower Gardens Oild Rigs are in 400 + ft. of water......even on 'air' the hard bottom is WAY past your MOD @ 187 ft. , ......so, do you plan to sit out that dive?

Karl

[scubafanatic]

I took my Nitrox class last night with four other folks at my local scuba shop Gypsy Divers in Raleigh, NC.

Two of the divers were buddies going on a trip to Bonaire that had free nitrox, another was a nice RN from a local hospital. The last person was the subject of this thread.

He was a nice, and very funny guy, from Romania. However, he plainly stated during the introductions that he didn't believe in Nitrox and probably wouldn't ever use it. Now I'm all for taking specialities for the heck of it, I may take the UW photography just to see if I like it. However, it struck me as odd that he would go through this non-diving dive training if he didn't plan to use it.

Everyone in the class immediately asked, "Why?", to which he responded that he was just taking the class as a stepping stone to trimix in the future. I know a little about trimix but I don't know enough to know if nitrox training is a requirement.

I was just wondering if anyone else considered it odd, or if it was the norm in some cases for people that knew they wanted to go straight into Tech diving? Also is there any link between nitrox and trimix?

...not to make too fine a point of it, but your Romanian friend is a Nitwit !

.....has your friend priced a Trimix fill lately ......kinda pricey !!!

...secondly, just for grins, scribble down a list of your favorite potential dive trip locations, then check out the availibilty of Trimix there...and share your findings with the board...should be entertaining, to say the least!

......soon you will come to the realization that for the vast majority of the world's dive sites ( outside the caving community of Florida ,and the hard-core wreck-diving community near the shores of the industrialized world ) you will get down on your hands and knees and thank the Lord you can even get your hands on 'plain 'ol' Nitrox, much less Trimix !

Karl

[Kriterian]

...not to make too fine a point of it, but your Romanian friend is a Nitwit !

.....has your friend priced a Trimix fill lately ......kinda pricey !!!

Karl

Whoa, whoa. Not friend. Complete stranger with totally opposite views as me, heh. I don't want to be put in the same boat as this person, I just wanted to know if I was justified in thinking it odd.

[WillDiveForBeer]

...secondly, just for grins, scribble down a list of your favorite potential dive trip locations, then check out the availibilty of Trimix there...and share your findings with the board...should be entertaining, to say the least!

    ......soon you will come to the realization that for the vast majority of the world's dive sites ( outside the caving community of Florida ,and the hard-core wreck-diving community near the shores of the industrialized world ) you will get down on your hands and knees and thank the Lord you can even get your hands on 'plain 'ol' Nitrox, much less Trimix !

        Karl

Ohh Ohh!!!! Our friend Peter Jones (peterbj7) does Trimix in Belize

[Diverbrian]

...not to make too fine a point of it, but your Romanian friend is a Nitwit !

.....has your friend priced a Trimix fill lately ......kinda pricey !!!

        Karl

Whoa, whoa. Not friend. Complete stranger with totally opposite views as me, heh. I don't want to be put in the same boat as this person, I just wanted to know if I was justified in thinking it odd.

Yep, you were justified, LOL!

[intotheblue]

I don't anything about using mixed gas in your tires, but Argon works great at improving the thermal performance of the windows in your house!!!

It sure helps the dry suit, especially when in cold water breathing a helium mix!

[intotheblue]

[quote name='Diverbrian' date='Apr 27 2005, 06:15 AM']Whoa, whoa. Not friend. Complete stranger with totally opposite views as me, heh. I don't want to be put in the same boat as this person, I just wanted to know if I was justified in thinking it odd. [/QUOTE]
Yep, you were justified, LOL![/QUOTE]


The use of the term "friend" was my fault originally (me thinks)... and I meant it loosely! Very...

No "o'fence" intended...



ITB...

[Walter]

...could you clarify for me your logic here? If you use a PPO2 of 1.4 ATA on air , your MOD is 187 ft. If you used EAN 32, your MOD @ 1.4 ATA PPO2 is 111 ft.

...... it appears to me, that if you'd dove the walls of Turks & Caicos ( as I just did during my 27 dives 2 weeks ago on the EXPLORER) with hard bottoms ranging down to 6000 ft. , and something went wrong, with a 6000 ft. 'hard bottom' you'd be pretty much be just as screwed diving 'air' as EAN32, a 76 ft. differential doesn't seem to make a material difference when viewed against a 6000 ft. deep backdrop.

I'll be happy to clarify. There are times when I've gone down for people who kept right on going deeper. In such an emergency, I'd be able to go much deeper to make the rescue on air than on nitrox. You're correct, I wouldn't be able to go to the bottom, nor would I want to do so. OTOH, I'd be able to bring up a diver on air that I'd have to let die if I were on nitrox. I'm not the one who'd be screwed if I choose to dive nitrox on a wall.

.......gotta warn ya, the Flower Gardens Oild Rigs are in 400 + ft. of water......even on 'air' the hard bottom is WAY past your MOD @ 187 ft. , ......so, do you plan to sit out that dive?

No. I'll happily dive it on air and I'll stay at a reasonable depth unless I have to go after someone.