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EuphoriaII
04-20-2008, 11:53
I'm thinking about taking a Nitrox course and have heard how you don't feel as tired after diving. I was wondering if it's really worth it? I don't feel all that tired anyway when I'm done but thought I would get others opinions

UCFKnightDiver
04-20-2008, 12:17
the tired part is somewhat debateable I havent seen any evidence that says it makes you less tired tho some people do swear that is the case, but it is safer to dive so I would get the cert, its a great class and you gain alot of great knowledge from it too

Largo
04-20-2008, 13:03
As God is my witness, I feel much better after a dive when I use Nitrox.

The only problem I have with Nitrox is that some divers try to push the depth limitations. They don't obey their Nitrox dive tables.

Oxygen toxicity is different from nitrogen loading.

Is there a physician who dives out there, who can explain the mechanism better?

reactive
04-20-2008, 13:09
Nitrox does not make diving safer. Yes, you decrease your nitrogen absorption, but you increase your oxygen exposure. There are a whole new set of guidelines that you must stay in when diving nitrox and just like air, if you stay withing those guidelines, it is safe.

The major advantage to diving nitrox is to increase your down time and decrease surface intervals needed to make multiple dives in one day. I don't know about you, but I like the idea of running out of gas before my no-deco time limit is up!

reactive
04-20-2008, 13:10
Sorry if that is a cheesy reply, but I am enrolled in the class right now, and that information is almost straight out of the book.

ReefHound
04-20-2008, 13:13
Is it worth it? Depends on the dive profiles. Nitrox is great for extending bottom times in the 60 to 100 foot range, especially on intensive repetitive diving.

I would disregard any reasons like "feeling better". Some perceive this and some don't, either way it is unproven. I would also be wary of saying "it is safer". It can be more dangerous - even lethal - if used incorrectly. There is a reason you need a special cert just for nitrox.

DougNR
04-20-2008, 13:14
I'm thinking about taking a Nitrox course and have heard how you don't feel as tired after diving. I was wondering if it's really worth it? I don't feel all that tired anyway when I'm done but thought I would get others opinions

You'll get a mixed response on the "feel better" issue. The reason I finally went down that road is because with my kids off at school, I don't have my usual dive buddies, leaving me at the mercy of insta-buddies.

This is not a rant on that topic, but with the popularity of nitrox a lone air only diver can be an unpopular situation. I can't blame a nitrox diver for not wantifng the limitation of having to dive the air tables because of the luck of the draw.

Do the nitrox course. If nothing else it gives you more options for your dive conditions and the group you dive with.

Good luck.

UCFKnightDiver
04-20-2008, 13:23
sorry I was referring to alot of my profiles, that would be the same regardless of nitrox vs air in this case it would be safer

this is assuming you follow the clock, mods etc....

cummings66
04-20-2008, 15:00
The major advantage to diving nitrox is to increase your down time and decrease surface intervals needed to make multiple dives in one day.

I'm not sure what brand class you're taking, but my course did not say you could decrease your SI. In fact it went on to point out that you should have a 1 hour SI just like diving air.

Now in real life how you use the reduced nitrogen absorption is up to you, you can decrease the SI, you can increase the bottom time, you can decrease the deco stop time, depending on how you employ it things vary in the relative safety.

As to toxing, well, VENTID but you should be aware that many times you won't know you're going to tox until you do. It's been proven many times over that sometimes the first symptom you notice is the tox event itself. It's similar to narcosis as well so sometimes you might confuse the two, causing problems. IMO treat any odd things as potential tox and start up. I think they say 3 to 5 minutes is about how long it takes to purge the excess O2, so heading up won't stop the tox event if it's scheduled to happen in the next 30 seconds, you're still going to experience it.

The Deco Stop benefit won't be in your Nitrox class, that's an advanced course but it is another benefit of Nitrox. In the end, take it seriously and be aware of what can happen. The results are worthwhile for using it IMO and for me my usage is mostly for the benefit of less Nitrogen loading. I still do the SI as if I'm on air.

reactive
04-20-2008, 15:28
My point was that if you're on gassing less nitrogen, it will take less time to off gas if you're planning on making another dive. Instead of a 5 hour surface interval using the tables to get down to 60 ft for another 20 minutes, you may only need one hour at the surface to off gas. I don't have my tables in front of me and I'm not so good with them that I have the material memorized well enough to spout off the table from memory, so keep in mind that the numbers I used are purely an example.

Just browsing at the tables you can see that there is a significant increase in how long you are able to stay down and the surface intervals for repetitive dives. I was not saying that you shouldn't do a 1 hour recommended surface interval.

ReefHound
04-20-2008, 16:26
My point was that if you're on gassing less nitrogen, it will take less time to off gas if you're planning on making another dive. Instead of a 5 hour surface interval using the tables to get down to 60 ft for another 20 minutes, you may only need one hour at the surface to off gas. I don't have my tables in front of me and I'm not so good with them that I have the material memorized well enough to spout off the table from memory, so keep in mind that the numbers I used are purely an example.

Not necessarily. If you dive nitrox to the nitrox NDL you will be as nitrogen loaded as diving air to the air NDL. If you use nitrox on an air profile you won't be as nitrogen loaded. You can have one or the other, longer bottom times or less nitrogen loading.

RoyN
04-20-2008, 16:49
I don't believe in that tired thing with nitrox. I use nitrox all the time and I still get tired, but thats after doing alot of swimming and burning my fat. ;) But seriously, don't take nitrox just because you hear people saying "how, it makes you awake more then air" and stuff. Anyways, I use nitrox because I wannna hide underwater and peek at the woman in tight wetsuits. :spyme:

Athena2c
04-20-2008, 19:57
I just got certified in January, because for the repetitive tropical dives I like to get in on vacation, it is safer.
Personally, I felt less tired diving nitrox than diving air....not that I wasn't tired, I was just less tired.

ChrisA
04-20-2008, 20:09
I'm thinking about taking a Nitrox course and have heard how you don't feel as tired after diving. I was wondering if it's really worth it? I don't feel all that tired anyway when I'm done but thought I would get others opinions

I think the newer Nitrox books teach that the "no so tired" and "it's safer" aspects of nitrox were a myth. I agree. Myths.

But it is "worth it" to do Nitrox for other reasons. Nitrox can give you more bottom time if you dive at a depth where nitrox can be used. This effect is minor if you do just one dive but if you are doing multiple dives it pays off well. And if you are doing a multi-day trip it really pays off. Just look at the dive tables for air and EAN32 to see,

RECDiver
04-20-2008, 20:12
I have been diving Nitrox since 1995 and love it. Yes, I feel better after an EAN dive than an air dive, for a couple of hours, then it catches up to me.

scubasamurai
04-20-2008, 20:30
i know everyone that i am going with to do a liveaboard swear by the eanx to reduce nitrogen loading over the course of many dives. up to 5 a day. they all swear that it makes them feel "less tired", but even after doing 5 dives on eanx, i think your going to be tired. i will let you know, because i rarely dive eanx, but i am going to try it on this live aboard to see how i feel. i did 3 days of diving total of 10 dives and was wiped out. hit the bed at 8 pm!!! on air so i will see how the eanx affects me doing this many dives.

UCFKnightDiver
04-20-2008, 20:59
I'm thinking about taking a Nitrox course and have heard how you don't feel as tired after diving. I was wondering if it's really worth it? I don't feel all that tired anyway when I'm done but thought I would get others opinions

I think the newer Nitrox books teach that the "no so tired" and "it's safer" aspects of nitrox were a myth. I agree. Myths.

But it is "worth it" to do Nitrox for other reasons. Nitrox can give you more bottom time if you dive at a depth where nitrox can be used. This effect is minor if you do just one dive but if you are doing multiple dives it pays off well. And if you are doing a multi-day trip it really pays off. Just look at the dive tables for air and EAN32 to see,

I think it depends on the way you use nitrox to determine whether its more safe or not.

skdvr
04-20-2008, 21:57
EANx is just like air in the respect that if you push it to the limits you are getting into a dangerous position, the thing about NITROX that makes it more dangerous (if you are pushing the NDL) is OxTox. As it has already been mentioned that it will hit you without much warning, if any warning at all. If you are saying that being able to dive to 60ft on air for 55 min (air NDL) and to 60ft for 90 min on EANx 32 (EANx 32 NDL) makes Nitrox safer then you are mistaken. If you do a dive to 60ft with your buddy and he in diving air so you are sticking to his NDL then yes the person diving EANx 32 would have less Nitrogen in their system, and there for be what some would consider "Safer".

All things considered, Nitrox is safe to dive as long as you understand the limits of what the advantages and drawbacks are. I personally like to dive Nitrox when I am doing deeper dives even if my buddy is diving air. I do not get to stay down longer, but I do have less of a N2 load. If I plan an doing a lot of diving over an extended period of time I too would probably elect to dive with nitrox if it is available. I have never noticed it making me less tired though. As others have mentioned though, there are people that swear that it makes them feel better, and you cannot argue with that. Just because it does not affect me that way does not mean that it does not effect them that way.

Phil

mike_s
04-20-2008, 22:34
I think it's worth it.... why? because I feel less tired at the end of the day and also you can typically get in more dives per day diving nitrox.


There reportedly are "studies" where they took a group of divers and had them all dive an air profile at a safe max op depth. THey have half the group nitrox and the other half air, but didn't tell either group what they had. They all dove the same profile for the same amount of time. After the dive they asked who was more tired and who wasn't. the alleged results are that the divers who dove nitrox weren't able to tell they felt better diving it and those who dove air couldn't say for sure that they were "more tired.


Now.... here's my "test".

about 2 years ago, I did a week trip with 5 days diving. I did dive days 1,2,3 on nitrox, then on day 4 switched to air, then on day 5 switched back to nitrox. All other after dive day activities were similar, so nothing to skew the 'test' results.

The 'nitrox days' I was fine that evening after diving. The day I dove air (90' dive and 80' dive), I couldn't wait to get in bed that night.

so.... my summary after diving that above test was that diving nitrox I wasn't as tired later in the day. So to me it's worth the extra few bucks. but that's just my opinion.

test two, last summer I did 27 dives over 6 days on a liveaboard. all the dives were nitrox of some percentage, though a few shallow ones were just nitrox tanks topped off with air for average 26% EAN. A few things to observe about this test.
1.) it would have been hard to do this many dives on air in this time period.
2.) If I had done as many as I could like this on air, I would have been dead dog tired at the end of the day.
3.) diving the nitrox mixtures gave me more bottom time on these repetitive dives that I wouldn't have been able to do over and over again with just diving air. One of the people on the trip was diving nitrox but on air computer profiles. He had to end his deeper dives much quicker than we did for example.


I dove 2 computers on the above liveaboard, in case one failed. Next time I try a trip like that I'd like to dive a 3rd computer just for test purposes. The test I want to try is to leave it in air mode and see how quick it locks up on the same deep profiles. (just an idea...)

Largo
04-20-2008, 22:38
I don't know what the X factor is, but I swear that I do not feel tired, after a day of diving Nitrox.

ChrisC
04-20-2008, 23:43
Regarding SI, here is an excerpt from the SDI Nitrox manual:

"The minimum recommended SI for divers using Nitrox is 30 minutes, although a 60 minute interval is preferred. After long dives/extended exposures, a two hour, 120 minute, SI is recommended. This is because when you dive Nitrox you are breathing higher than normal PO2, and your body needs a period of time to compensate for that exposure. A 60 minute SI definitely reduces the risk of having an O2 "hit" when conducting multiple dives."

For me the tangible benefit is the increased bottom time, which IMO makes EAN worth it. I think it would be very difficult to accurately gauge "less tired" from a scientific perspective. I do believe, however, that if you personally feel less tired after diving EAN; that's great! I also think that if you believe you are going to be less tired after diving EAN, you probably will be. Either way it is a win! Longer bottom time for sure, less tired if you're lucky, as an added benefit. In any case, I think it is worth it. (IMHO)

mike_s
04-21-2008, 11:27
Regarding SI, here is an excerpt from the SDI Nitrox manual:

"The minimum recommended SI for divers using Nitrox is 30 minutes, although a 60 minute interval is preferred. After long dives/extended exposures, a two hour, 120 minute, SI is recommended. This is because when you dive Nitrox you are breathing higher than normal PO2, and your body needs a period of time to compensate for that exposure. A 60 minute SI definitely reduces the risk of having an O2 "hit" when conducting multiple dives."





I doubt that SDI, PADI or any other agency did any extensive testing of these surface intervals on a scientific basis. I'm sure those recomendations are further impacted by review of their legal department for liability purposes.

You computer should be able to calculate your o2 toxicity based on your surface interval time. I've had a couple incidents where I approached o2 limits and my computer(s) caught them each time.

MicahEW
04-21-2008, 15:05
I just recently finished my classroom part for my EANx class with NAUI and its a good class to have more math though. It really is a safer gas too.

berick
04-21-2008, 15:10
Question was "Is it worth it". That is a subjective question that depends on the cost of the nitrox, how much you value money, and your perceived benefits from diving nitrox. The only way you'll know is to take the Nitrox course, dive nitrox for some dives, and evaluate how you feel, your dive enjoyment (including bottem and SI time, etc) versus the additional cost using your decision calculus. Personally, I feel it is worth it for multiple dives during a week at $125 -$200/week but I can't point to any hard data from my dives to justify it.

mike_s
04-21-2008, 15:10
. It really is a safer gas too.

Don't believe that to be 100% true. It is only safer in some aspects and in how you use it. I can be more dangerous also if you for example exceed the MOD (Max Operating Depth) for a certain mixture.

So don't always think you're safer on it.





, I feel it is worth it for multiple dives during a week at $125 -$200/week but I can't point to any hard data from my dives to justify it.

Here is some hard data. On a liveablard trip, I think our Nitrox upgrade was $150 bucks. However, diving Nitrox, I was able to do more dives per day as opposed to someone diving air tables. Therefore I was able to get in more diving in the same one week period, increasing my total number of dives for the trip. To me, that justifies it alone.

MicahEW
04-21-2008, 15:24
Question was "Is it worth it". That is a subjective question that depends on the cost of the nitrox, how much you value money, and your perceived benefits from diving nitrox. The only way you'll know is to take the Nitrox course, dive nitrox for some dives, and evaluate how you feel, your dive enjoyment (including bottem and SI time, etc) versus the additional cost using your decision calculus. Personally, I feel it is worth it for multiple dives during a week at $125 -$200/week but I can't point to any hard data from my dives to justify it.


very true it safely increases your bottom times would be a better statement.

CompuDude
04-21-2008, 15:27
Question was "Is it worth it". That is a subjective question that depends on the cost of the nitrox, how much you value money, and your perceived benefits from diving nitrox. The only way you'll know is to take the Nitrox course, dive nitrox for some dives, and evaluate how you feel, your dive enjoyment (including bottem and SI time, etc) versus the additional cost using your decision calculus. Personally, I feel it is worth it for multiple dives during a week at $125 -$200/week but I can't point to any hard data from my dives to justify it.


very true it safely increases your bottom times would be a better statement.

... under the right circumstances, that is.

It doesn't increase your BT in all circumstances. There is a sweet spot where common mixes are very effective at allowing more BT, however.

ReefHound
04-21-2008, 15:51
It only increases your BT if you have the available gas to use it. For instance, the NDL limit for 32% Nitrox at 60 feet is 90 minutes. The NDL limit for air at 60 feet is 55 minutes. That's a potential 35 minutes additional dive time. But if your air pressure is down to your ascend pressure after 55 minutes, you aren't going to be able to take advantage of it. Unless you get a bigger tank.

Sounder
04-21-2008, 17:24
Nitrox is the ONLY thing many of my friend and I dive. There is a funny saying that "air is 'tire-gas'." I feel much better on a mix than I do on straight air at the end of a big diving day.

Nitrox is popular enough up in the PNW area that there are LDS's who sell annual all-you-can-eat nitrox fill programs at the beginning of each year.

ReefHound
04-21-2008, 17:54
If you never dive air then how do you know air makes you tired?

harb99
04-21-2008, 18:00
It only increases your BT if you have the available gas to use it. For instance, the NDL limit for 32% Nitrox at 60 feet is 90 minutes. The NDL limit for air at 60 feet is 55 minutes. That's a potential 35 minutes additional dive time. But if your air pressure is down to your ascend pressure after 55 minutes, you aren't going to be able to take advantage of it. Unless you get a bigger tank.

true, but as Mike stated above


However, diving Nitrox, I was able to do more dives per day as opposed to someone diving air tables. Therefore I was able to get in more diving in the same one week period, increasing my total number of dives for the trip. To me, that justifies it alone.

which is why I am planning to take nitrox and use it on our trip to Bonaire, especially since the nitrox upgrade was free.

ReefHound
04-21-2008, 18:08
I'm a big fan of nitrox and I think it is worth it, but getting in more dives is also situational dependent. If you are already getting in the max number of possible dives on air then you won't be getting in more dives. Actually, your limit can be lower under nitrox because you have a limit on total oxygen exposure within a 24 hour period, often called the "CNS clock".

Sounder
04-21-2008, 18:31
If you never dive air then how do you know air makes you tired?
Fair ball.

I used to dive air in the past and would find myself feeling different than when I dive nitrox. I've also done controls to see whether this is actually true for me or not... and I find it to be true, at least for me. Some folks I dive with don't feel any different.

Sounder
04-21-2008, 18:36
I'm a big fan of nitrox and I think it is worth it, but getting in more dives is also situational dependent. If you are already getting in the max number of possible dives on air then you won't be getting in more dives. Actually, your limit can be lower under nitrox because you have a limit on total oxygen exposure within a 24 hour period, often called the "CNS clock".

This is something we watched carefully in Bonaire - doing 4-5 one-hour dives per day on nitrox required us to monitor it carefully. We planned our dives accordingly so we would have shallow dives that were still interesting and "must do's" when it was to our advantage to do them... and deeper dives accordingly too. With good planning, we weren't limited in our dive plans throughout the trip.

Ox Toxing is DEFINITELY not something to screw around with. If you don't know how to calculate your O2 exposure other than by just watching your computer, get back on the books and with your instructor for a review.

cummings66
04-21-2008, 22:52
You mean do it by hand, as in the OTU=t(PO2-.5)raised to .83 divided by .5

Or the CNS which is the bigger limit where you refer to a chart for the number, ie 1.4 ATA is .67 %CNS/Min and then do the math to arrive at the O2 pressure time limits? Keeping in mind you don't want to exceed 80% of the maximum allowable dose.

The funny thing is, for my TDI tech class they teach us the formulas to do what you're wanting this guy to do, then we're told we can use a computer to keep track of it as the math is pretty involved and the computer is more accurate because it keeps track of depths better.

I'm not sure why I have all the formulas floating around in my head. I can do all of them with referrig to a book, but it's just not as easy as looking at that plastic card or asking the computer for the answer.

Like diving in general, I believe it's bad to rely 100% on a computer and fail to keep track of data yourself, but if you do dive with a computer you can get to a point where if it quit you're got to stop diving because you're so far off the tables you'll never find your way back.

Sounder
04-22-2008, 12:04
You mean do it by hand, as in the OTU=t(PO2-.5)raised to .83 divided by .5

Or the CNS which is the bigger limit where you refer to a chart for the number, ie 1.4 ATA is .67 %CNS/Min and then do the math to arrive at the O2 pressure time limits? Keeping in mind you don't want to exceed 80% of the maximum allowable dose.

The funny thing is, for my TDI tech class they teach us the formulas to do what you're wanting this guy to do, then we're told we can use a computer to keep track of it as the math is pretty involved and the computer is more accurate because it keeps track of depths better.

I'm not sure why I have all the formulas floating around in my head. I can do all of them with referrig to a book, but it's just not as easy as looking at that plastic card or asking the computer for the answer.

Like diving in general, I believe it's bad to rely 100% on a computer and fail to keep track of data yourself, but if you do dive with a computer you can get to a point where if it quit you're got to stop diving because you're so far off the tables you'll never find your way back.

I guess my basic caution is not to follow and trust a computer to where you depend on it... when you're strictly watching O2 and N "bars" on your computer, you should really have an idea, manually, of where you are.

EuphoriaII
04-22-2008, 14:37
Most of my dives will be on dive boats so my surface interval will be at the mercy of the air breathers anyway. My bottom time could be a little more on boats that allow you to dive your own profile (which I prefer) but not so much longer as to hold up the boat.
The 'instabuddy' matchup makes good sense in the event you are paired with a Nitrox diver although I plan to be diving with my sons for a couple more years.

coral cowgirl
05-24-2008, 19:02
I'm planning to dive Nitrox with my air breathing buddies and just use air tables for built in safety factor (and of course observe maximum prescribed depths.)

cutter77
05-31-2008, 20:17
Here is some hard data. On a liveablard trip, I think our "Nitrox upgrade was $150 bucks. However, diving Nitrox, I was able to do more dives per day as opposed to someone diving air tables. Therefore I was able to get in more diving in the same one week period, increasing my total number of dives for the trip. To me, that justifies it alone."
__________________
Agreed, I don't really "feel any better" when diving Nitrox...but I like the extra bit of bottom time it can allow.

navyhmc
05-31-2008, 21:30
Like diving in general, I believe it's bad to rely 100% on a computer and fail to keep track of data yourself, but if you do dive with a computer you can get to a point where if it quit you're got to stop diving because you're so far off the tables you'll never find your way back.

I guess my basic caution is not to follow and trust a computer to where you depend on it... when you're strictly watching O2 and N "bars" on your computer, you should really have an idea, manually, of where you are.

I agree. Usually, what I will do is at the 10 minute surface interval mark, I will put the computer into planning mode, look at my NDL for 60' (Any depth would work I guess, but for some reason, I like 60'-come to think about it, 50' might be better.) then note what the difference is between that and the 55 minutes if I'm on air or whatever the first dive NDL is for my mix. Then go to the Residual Nitrogen part of my tables-I use PADi so it's on the back side-and note which RNT my computer calculated RNT is in the range of and work the dive backwards until I get my Surface group. This has helped the time my computer crapped out-or, more to the point, someone accidently put it into guage mode when he shouldn't have.

Example: After 10 minutes on the surface, my 60' NDL is 37 minutes I was on air so I still have 18 minutes of RNT. This makes me an "F" diver so my Initial Surface group was "G". Now, if the computer craps out, I have a good starting point. Like so many other things on tables, if you're between groups, round up as this will err on the side of caution, conservative diving and safety.

Fireplug
05-31-2008, 22:01
I did my first nitrox dives in Key Largo in May. Usually doing 5 dives a day, 2 morning, 2 after and a night dive, I was dragging by the time I got done. By doing the 2 afternoon dives on Nitrox I felt great. Energized and everything. At least with this fat boy, it made a big difference.

Merrimorte
07-12-2008, 02:42
Another added benefit, provided you do not dive deep... is the extended bottom times. Depending on your depth you can extend you tbt (from 10 min to close to 40%) but again it depends on depth... Nitrox is not a deep diving mix... it just has less nitrogen and more oxygen in it than air... which also means less to off gas later.

To know if it is worth it for you, you need to determine just what kind of diving you will be doing. Grab a nitrox table and look at it, that might help.

Merri

SlvrDragon50
07-13-2008, 23:15
What is the class like? It seem highly beneficial to do this if staying at ~40"

CompuDude
07-14-2008, 17:11
What is the class like? It seem highly beneficial to do this if staying at ~40"

If you're not diving below 40 feet much, Nitrox will be of limited benefit. It could help you feel better after the dives (if that's currently an issue for you... and if it's not the placebo most tests have shown it to be). It also theoretically makes things a little safer, since you'll be taking on less nitrogen but still well within limits. Practically speaking, though, the limits are so long for dives in that range, I see little reason to spend the money on a Nitrox fill for dives that are so shallow, unless perhaps you're on an unlimited Nitrox plan, and then sure, absolutely.

digitalman
07-14-2008, 17:24
What is the class like? It seem highly beneficial to do this if staying at ~40"

If you're not diving below 40 feet much, Nitrox will be of limited benefit. It could help you feel better after the dives (if that's currently an issue for you... and if it's not the placebo most tests have shown it to be). It also theoretically makes things a little safer, since you'll be taking on less nitrogen but still well within limits. Practically speaking, though, the limits are so long for dives in that range, I see little reason to spend the money on a Nitrox fill for dives that are so shallow, unless perhaps you're on an unlimited Nitrox plan, and then sure, absolutely.

Pretty much exactly what I would have said. Generally speaking, a single tank dive less than 40 ft will exhaust your air supply before you exhaust your bottom time. A dive in the 80-100 ft range extends your bottom time significantly enough that you could also run through a full tank, where as with air, you'd have to end the dive sooner because of the Nitrogen loadings. If you frequently dive deeper than 110 ft, depending on your O2 mix, you'll be limited by the depth rather than the tank capacity due to increased O2 loadings which do not have a significant bearing on air dives. You'll learn about this in class.

Take the class, get the card, and make the decision yourself based on your dive profile whether or not you should dive with Nitrox.

digitalman
07-14-2008, 17:29
I forgot to add the 'feeling better' part. Personally, I haven't noticed any difference between diving air and diving nitrox. If it's a difficult dive (currents, overweighted), you'll get tired no matter what you're breathing. The best way to feel good after a dive is to be in shape before you start the dive. I can say this because I'm admittedly not in shape.

chinacat46
07-14-2008, 18:05
There are alot of people who say after diving with Nitrox that they feel less tired. I think it's in their minds and if they feel less tired fine but there is no proof backing this up. I think it's really the opposite since if you are diving Nitrox you tend to dive longer so you will be more tired. Again there is no proof for that except that you are exercising longer.

mitsuguy
07-14-2008, 18:36
all I know is that on our last dive trip to the Texas Clipper, my wife and I were first in the water, last out, shortest SI, first back in the water, last out, and still had plenty of no-deco time remaining, and our dives were turned by her on a steel HP80 tank and her measly .35 sac rate... obviously this was on 32% nitrox, whereas most everyone else was on air...

Truered1
07-14-2008, 22:03
Personally, I haven't found it to be worth the cost of the Nitrox fills yet. I was certified in April and dive almost every week. At 60 - 100' I am only getting 6 - 8 minutes more bottom time if that. As far as being tired I don't feel any different. I have done my own testing diving the same wreck and reef a week apart, one on air, the other on 32 EAN. The difference on the wreck was 4 minutes at 88' and on the reef 6 minutes at 66'. Yes I did get 10 minutes more bottom time but is it worth double the cost of the air fill. Personally doing only 2 dives a day I would save the the $$ for another day. BUT if I was on a live aboard I would definitly use the Nitrox for the all around benefits. Thats my 2 cents, hope it helps.

JillianAnnO
07-14-2008, 22:17
I don't really ever feel tired after a dive... I just feel whipped after carrying the equip to my point of entry!

CompuDude
07-14-2008, 22:25
Personally, I haven't found it to be worth the cost of the Nitrox fills yet. I was certified in April and dive almost every week. At 60 - 100' I am only getting 6 - 8 minutes more bottom time if that. As far as being tired I don't feel any different. I have done my own testing diving the same wreck and reef a week apart, one on air, the other on 32 EAN. The difference on the wreck was 4 minutes at 88' and on the reef 6 minutes at 66'. Yes I did get 10 minutes more bottom time but is it worth double the cost of the air fill. Personally doing only 2 dives a day I would save the the $$ for another day. BUT if I was on a live aboard I would definitly use the Nitrox for the all around benefits. Thats my 2 cents, hope it helps.

I look at it like this. Considering the amount of time, money and effort it takes to get the measly amount of bottom time we actually get to enjoy, it's WELL worth an extra $6 to get 10-30% more bottom time.

Add up the amount of time you spend prepping gear for a trip, traveling to the dive site (or boat, and then travel time), breaking down gear after the dive, and traveling home. The number is HUGE compared to the lousy hour or two you get in the water. If I can squeak an extra 15 minutes or so per dive out, by diving Nitrox, it's way worth it. (Also note that you can be back in the water again that much faster with Nitrox)

coral cowgirl
08-07-2008, 14:36
Yep, spending $5,000 for an exotic trip, not to mention the hassle of getting half across the planet .......would be well worth it to get that extra bottom time. Wonder what it would figure out to timewise for a typical 7-10 day trip.

JimHar99
08-07-2008, 16:09
More bottom time. Nitrox is defeinatly worth it, especially on those dive vacations where you can get 5 dives a day. On my last dive vacation (Bonaire - Plaza) the nitrox was free.

Rockhound76
08-12-2008, 17:22
I will dive air on most of my trips. The last time I did the Flower Gardens, I had pretty good headache about the 6th dive. This is common for me.

I may go back out there next month, an plan to dive EAN exclusively. I let ya'll know if I feel better breathing geezer-gas.

I put my son (15) on EAN, but leave him diving air tables. Because of where we dive, most of his dives are below 60'. I would prefer to lower his nitrogen stress, as MOD and CNS toxicity are not big issues (we haven't come close to the limits yet). I will also dive on air table (algorithms) with him, so as to have at least some clue as to when he might be coming close to his air-based NDL (he watches his gauges close, but I like to keep up with this info).

My backup is set to EAN, so I can see the difference.

stairman
08-12-2008, 17:51
When Im cave diving I exclusively breathe 32%.I do alot less deco than I would on air.100% at twenty and Im up even quicker.One thing you MUST remember,always analyze your mix before breathing it.I would take the class if I were you.

MSilvia
08-12-2008, 18:11
Whether or not you ever use nitrox, in my opinion the class is well worth it because it opens a door to understanding what effect the gas you're breathing has on you and your diving.

That aside, I've been working on a spreadsheet that calculates your maximum bottom time based on "rock bottom" pressure required for you to safely surface while sharing gas with an OOA buddy (assuming a buddy with a SAC of 1.0), and compares that available time to the NDL times for air, EAN32, and EAN36 for a single dive and several different repetitive dive pressure groups. If the limiting factor on the dive is your rock bottom time, the NDL will be shown in green. If the limiting factor is your NDL, it will be shown in red. Mind you, this is a work in progress, and I make no warranty as to it's accuracy, or your safety if you're foolish enough to use it for dive planning knowing that it probably contains errors.

In any case, you might find it useful for deciding if nitrox is "worth it" for the kinds of dives you do. Just enter your SAC rate, and your tank's volume and service pressure in the top left corner of the table. The rest should be worked out automatically.

Enjoy, and let me know if you have any ideas for improvements.
http://thedecostop.com/matt/nitrox.xls

Gombessa
08-12-2008, 18:43
In the end, Nitrox is worth it if your bottom times are NDL/MDL-limited rather than gas-limited. Most of my diving is in the 40-60ft range, so with 50-170mins at my disposal, I'm rarely in a situation where Nitrox would have a significant advantage over air.

hooligan
08-12-2008, 19:27
In the end, Nitrox is worth it if your bottom times are NDL/MDL-limited rather than gas-limited. Most of my diving is in the 40-60ft range, so with 50-170mins at my disposal, I'm rarely in a situation where Nitrox would have a significant advantage over air.

Get Doubles!!:smiley2:

PhD4JC
08-12-2008, 20:03
I usually come up with the most psi left.
I dive NITROX to reduce likelihood of DCI.
Even if you do everything right, you can end up with DCI, and being a voluptuous woman, I have more tissue that is prone to N absorption.
SO I dive nitrox to reduce the amount of offgassing and for peace of mind...

character157
08-12-2008, 20:06
I intend to get Nitrox Cert this winter, but I don't think I will dive Nitrox all the time. On a single tank its not a big deal...If its more than one or two in a day it would be worth the extra cash to decrease my chances of DCS. I say its worth it depending on the diving you do especially if you are doing a liveaboad.