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mulefeathers
09-17-2007, 11:52
The other day my LDS called to notify me about a Nitrox class starting next week. The price is $140.00 not bad I guess. After thinking about it and discussing it with my LDS, the question still remains. What do I need Nitrox for? What is the advantage? I started diving for the purpose of shooting fish. I can do that in 40 feet of water. But anyway this morning reading about nitrox diving I stumbled across several online certification sites. This one in particular is at the top of the list when I googled the subject.

http://www.onlinenitroxlessons.com/index.html

So now the question is does anybody use these sites or would you use an online site to get certified for nitrox.

finflippers
09-17-2007, 12:25
Many Nitrox courses don't have any active dives to do for certification. Every thing about Nitrox is learning the uses and limits of it and can be done online if so desired. The only thing that you will not be able to do online that you need to be able to do is analyze your tank.

I took my course at a LDS and would recommend the same only because I like the ability to ask questions and learn in person.

finflippers
09-17-2007, 12:31
I noticed that the certifying agency is SDA. Is SDA acccepted everywhere?

ScubaToys Larry
09-17-2007, 12:33
The web site you found is not recognized by any training agency that I know of. If you walked into my shop with a card from them, we could not give you nitrox. No problem with Naui, Padi, SSI, TDI, YMCA, etc... but that is actually just a site a guy made - and not affiliated with any of the agencies.

mulefeathers
09-17-2007, 12:38
Well I am not going to use them. I was just kinda shocked to find somebody offering scuba certs online. Again I was not looking for that type of website it was the first item on the list on google. I was trying to learn why I should be certified for nitrox.

finflippers
09-17-2007, 12:44
Nitrox offers either longer bottom times or greater margin of safety.

mulefeathers
09-17-2007, 12:58
Nitrox offers either longer bottom times or greater margin of safety.


Yeah that is what everything I have read said as well.

Thanks

finflippers
09-17-2007, 13:15
Nitrox offers either longer bottom times or greater margin of safety.


Yeah that is what everything I have read said as well.

Thanks


If you was to dive Nitrox as it it was air then you would have less chances of getting bent. If I am doing more then one dive in a day I try to dive nitrox and use it as if it was air.

If you push your NDL close to the limits then again diving Nitrox as if it was air would lessen your chances of getting bent.

If you want to get longer bottom times, then Nitrox will allow you to stay down longer then at the same depth with air but will not give any more safety then air because you are taking advantage of the longer bottom times.

Hope this helps

CompuDude
09-17-2007, 13:16
The other day my LDS called to notify me about a Nitrox class starting next week. The price is $140.00 not bad I guess. After thinking about it and discussing it with my LDS, the question still remains. What do I need Nitrox for? What is the advantage? I started diving for the purpose of shooting fish. I can do that in 40 feet of water. But anyway this morning reading about nitrox diving I stumbled across several online certification sites. This one in particular is at the top of the list when I googled the subject.

http://www.onlinenitroxlessons.com/index.html

So now the question is does anybody use these sites or would you use an online site to get certified for nitrox.
Nitrox, as said above, can either give you longer bottom times or an increased safety margin.

IMO, if you are doing the majority of your dives in 40' of water, Nitrox will be of little benefit to you. There is little risk of getting bent in 40' of water (AGE is another story, but Nitrox won't help you there), and the added bottom advantages don't really apply that shallow since you're almost never limited by NDLs at that depth.

Nitrox really hits it's stride between 60-100', IMO. There, you have notably increased risk of DCS (compared to 40' and less, at least) which the Nitrox can help with if you dive it on air tables, or if you're going for increased bottom time, it really adds a lot to how long you can stay down.

I would get the cert anyway, because it could be handy for vacation diving where the limits of your usual spots no longer apply, but it doesn't sound like something that's going to be critical to your style of diving.

I found the knowledge helpful and interesting regardless, but it's up to you if you want to take the class if you're not going to reap much in the way of benefits from it.

mulefeathers
09-17-2007, 13:22
Like I said the main reason I got into scuba was to shoot fish. In 40 to 60 feet I can shoot some nice fish. There may be a time that I would want to do some 100 foot dives so I am considering the class.

CompuDude
09-17-2007, 13:53
Like I said the main reason I got into scuba was to shoot fish. In 40 to 60 feet I can shoot some nice fish. There may be a time that I would want to do some 100 foot dives so I am considering the class.

Yes, once you get into the 60-100' range, it will be a big benefit, although don't forget your fills will start to be a lot more expensive. Definitely worthwhile to take the class diving that range, however.

sudnit5
09-17-2007, 14:28
How much more is the Nitrox compared to air?

ScubaToys Larry
09-17-2007, 14:29
How much more is the Nitrox compared to air?

about 5 bucks more per tank. Depending on where you are.

CompuDude
09-17-2007, 17:14
How much more is the Nitrox compared to air?

I get air for between free and $6/fill, depending on where I go. ($2-4.50 in the shops I normally go to)

Nitrox around here tends to be between $8-12/fill, again, depending on where you go. (I normally pay about $8)

If you dive a lot, the difference adds up, but the safety factor and /or increased bottom time make it worthwhile for me... for certain dives. I pick and choose my fills based on what I'll be expecting to encounter on my dive. I'll happily pay when it's worth it, but it's not worth an extra 20 min drive when I just need a quick refill so I can go do another 40' shore dive.

jo8243
09-18-2007, 11:55
I use it just for the safety factor, not really to extend bottom time. If you intake less nitrogen you should have less risk of DCS than you would with the same profile on air.

plot
09-18-2007, 17:30
my nitrox class involved me reading a book and answering questions before I got there... actually class was maybe 2 hours long discussing the book/answers (if anyone got any of them wrong), stressing a few points, and then using an o2 meter.

really, nothing to it, an online class would work just as well as a real class... it's all theory, stuff still breaths the same, nothing you gotta be trained on to dive it outside of how to do it safely, the risks involved, and the advantages involved.

diverdad
09-18-2007, 22:00
By the sound of it you would not gain any thing by taking the nitrox course unless you plan on going deeper.

mulefeathers
09-19-2007, 07:29
By the sound of it you would not gain any thing by taking the nitrox course unless you plan on going deeper.


Yes I agree. That is why I still have not spent the money for this class.

ScaredSilly
09-19-2007, 16:35
The best way to get a nirtrox cert is to go some place for a week and say I want to learn about nitrox will you throw that in with my stay if I do 10 nitrox dives. Many will.

plot
09-19-2007, 16:39
a common misconception for nitrox is that it's for going deep. although the advantages of more bottom time increase as you go deeper, it also limits your depth alot more severely than air does. on a normal 32% nitrox mix, the max depth you can goto is 111 feet.

The huge advantages to nitrox comes when you start doing repetative dives.

CompuDude
09-19-2007, 16:47
a common misconception for nitrox is that it's for going deep. although the advantages of more bottom time increase as you go deeper, it also limits your depth alot more severely than air does. on a normal 32% nitrox mix, the max depth you can goto is 111 feet.

The huge advantages to nitrox comes when you start doing repetative dives.

There's deep, and there's deep. The OP originally stated most of his dives were in the 40' range. Only later did he extend that to "possibly" doing some in the 60-80' range. Still not "deep", by my personal definition, but deep enough to start seeing some gains from nitrox.

ScaredSilly
09-19-2007, 16:49
on a normal 32% nitrox mix, the max depth you can goto is 111 feet.

Actually, you can go deeper. In fact as deep as you want. It might not be good for you but you can.

What you want to say: The maxiumum operating depth (MOD) for diving a 32% Nitrox mix and maintaining a PO2 of 1.4 is 111 feet. Two of the three need to be stated - one can not assume the PO2.

Those using nitrox during deco stops will typically use a PO2 of 1.6 so in this case they might be jumping on it at 132 feet.

Or in some cases there might be something at 120 feet you want to see so you might bounce down for 5 minutes at the beginning of the dive and then spend the rest at 100'.

jo8243
09-19-2007, 16:52
By the sound of it you would not gain any thing by taking the nitrox course unless you plan on going deeper.

That's not true. You gain a safety factor because if you are breathing less nitrogen there is less in your blood to cause bubbles... silent or DCS.

plot
09-19-2007, 16:57
a common misconception for nitrox is that it's for going deep. although the advantages of more bottom time increase as you go deeper, it also limits your depth alot more severely than air does. on a normal 32% nitrox mix, the max depth you can goto is 111 feet.

The huge advantages to nitrox comes when you start doing repetative dives.

There's deep, and there's deep. The OP originally stated most of his dives were in the 40' range. Only later did he extend that to "possibly" doing some in the 60-80' range. Still not "deep", by my personal definition, but deep enough to start seeing some gains from nitrox.

There's alot of other people throwing around the "diving deep" term though, which is why I wanted to clarify... since a WHOLE lot of people think it's a gas for going deeper than you would on air.



on a normal 32% nitrox mix, the max depth you can goto is 111 feet.

Actually, you can go deeper. In fact as deep as you want. It might not be good for you but you can.

What you want to say: The maxiumum operating depth (MOD) for diving a 32% Nitrox mix and maintaining a PO2 of 1.4 is 111 feet. Two of the three need to be stated - one can not assume the PO2.

Those using nitrox during deco stops will typically use a PO2 of 1.6 so in this case they might be jumping on it at 132 feet.

Or in some cases there might be something at 120 feet you want to see so you might bounce down for 5 minutes at the beginning of the dive and then spend the rest at 100'.

yea yea.. i left off the 1.4 po2, i concede. 1.4 is taught as the recreational safe limit by most agencies which is why i defaulted to that. :smiley2:

Bill22
09-19-2007, 18:14
I'm planning on taking my Nitrox course at the beginning of my dive trip to the Philippines next month. Since I'm planning 40-50 dives over 15 dive days, I felt the extra safety margin would be a good thing to have.

I had 30 Nitrox dives set up as part of my package. The air dives will be mostly early in my trip and for shallow depths where there is no risk of my even coming close to my NDL's.

There will be plenty of dives where I will take advantage of the additional bottom time, for deeper depths. With so many dives planned, I will dive with my computer set on air periodically to help outgas.

I also plan on diving Nitrox with my computer set on air the day before I fly from Cebu to Manila. I figure doing that coupled with waiting 24 hours should increase my safety margin when I fly.

I'll have at least 4 additional dive days before my final leg from Manila to Tokyo. I should be fine there as I will have at least 36 hours to outgas before heading home.

crpntr133
09-19-2007, 20:55
If I'm thinking right you still want to obey the no fly rules. I will assume that you mean that you will be waiting sufficient time.
The BIG advantage of nitrox is repetitive diving. Yes it helps with the NDL when going deeper.

Bill22
09-20-2007, 03:02
If I'm thinking right you still want to obey the no fly rules. I will assume that you mean that you will be waiting sufficient time.
The BIG advantage of nitrox is repetitive diving. Yes it helps with the NDL when going deeper.

Exactly... I still will wait at least 24 hours before flying, but by diving Nitrox with my computer set on air for the last day or two of diving, I will increase my safety margin. Sorry, maybe I could have explained that better ;-) Anyone would have to be pretty stupid to violate no-fly :-))

By periodically diving Nitrox with my computer set to air while doing repetitive diving during my trip, I will help reduce some of the increased risk of decompression sickness that goes along with making multiple dives in a short period of time.

Part of the advantage for me during this particular dive trip, is that I want to see Thresher Sharks. The increased bottom time will give me a better chance of accomplishing that, as they have been known to be shy ;-)

Off topic, but heres a link to one of the places where I'm diving:
http://www.malapascua-diving.com/

wgt
09-21-2007, 11:09
How much more is the Nitrox compared to air?
Many international tour operators do not charge extra for nitrox. Ask about it when planning a trip. It's a nice perk, and it indicates a committment to safety on the part of the dive operator.

wgt
09-21-2007, 11:25
By the sound of it you would not gain any thing by taking the nitrox course unless you plan on going deeper.

That's not true. You gain a safety factor because if you are breathing less nitrogen there is less in your blood to cause bubbles... silent or DCS.

I agree with Jo for two reasons. First, DCS is a possibility (remote though it may be) even in fairly shallow water. Second, even if one hasn't initially planned on diving deeper and has been diving shallow for several days on air, he/she will have accumulated substantial nitrogen in the slower tissues. Suddenly, somebody yells "Frogfish at 25 m (82 ft)!!" The nitrox breathed shallow will confer an advantage on the previously unexpected deeper dive.

Buoyant1
09-24-2007, 11:19
Nitrox offers either longer bottom times or greater margin of safety.


The best reason to get it! (or if you are over 40 or overweight you are predisposed to DCS, so it's a good safety valve!)

Bill22
09-24-2007, 15:14
Nitrox offers either longer bottom times or greater margin of safety.


The best reason to get it! (or if you are over 40 or overweight you are predisposed to DCS, so it's a good safety valve!)

Thats interesting... I didn't realize it started so young ;-)

texdiveguy
09-24-2007, 15:24
I'm planning on taking my Nitrox course at the beginning of my dive trip to the Philippines next month. Since I'm planning 40-50 dives over 15 dive days, I felt the extra safety margin would be a good thing to have.

I had 30 Nitrox dives set up as part of my package.


Sounds like a great time planned for sure.......not having a clue to your dive profiles planned--just keep track of your OTU's for the trip.

Have fun and be safe!

Bill22
09-25-2007, 20:42
I'm planning on taking my Nitrox course at the beginning of my dive trip to the Philippines next month. Since I'm planning 40-50 dives over 15 dive days, I felt the extra safety margin would be a good thing to have.

I had 30 Nitrox dives set up as part of my package.


Sounds like a great time planned for sure.......not having a clue to your dive profiles planned--just keep track of your OTU's for the trip.

Have fun and be safe!

Thanks! :-) I don't have to many deep dives planned. I'm quite content with what I find above 50 feet most of the time plus I get more bottom time ;-)