Nitrox

[JamieG]

Just wanted to know why people dive on nitrox (single tank sports diver stuff)?

I did the course yonks ago (I have a PADI Enriched Air card somewhere?) but never bothered with it again as it seemed a bit of a bugger about for not a lot more?

Am I missing something? Should I be diving on Nitrox? I have a mate who got bent last year on air and now dives Nitrox on air tables and reckons it gives him a greater safety margin?

From what I can remember (it was a while ago) you need to be sure of exact depth and mix? I have my book somewhere..............................

I don't dive deep enough to use it as a deco gass.

[scuba steve irl]

using nitrox within its depth limits give greater safty margins and lessins the effect of nitrogen narcossis .

the deeper ya go the more you should be using it . esspically if your diving close to the ndls on tables of air.

its fairly cheep and widly available

[Garf]

Originally Posted by scuba steve irl

using nitrox within its depth limits give greater safty margins

Only if you use it with an equivelent air table. If you use nitrox tables it will extend your bottom time but not add any safety factor.

and lessins the effect of nitrogen narcossis .

but obviously increases the effect of oxygen narcosis,, so depending on how narcotic you believe oxygen to be, there is no difference in the overall amount of narcosis.

the deeper ya go the more you should be using it . esspically if your diving close to the ndls on tables of air.

Again, only if you want to use nitrox to extend your bottom time rather than add a safety factor. Also Nitrox works well in the 40 metre range, deeper than it is arguable there are better options.

The nearest i get to breathing air is usually EAN25 when Ive air-topped a EAN32 fill to jump in for one more dive in a quarry.

[Rob Dobson]

Reduced decompression obligation - that's it. No reduction in narcosis although plenty of people claim that it does.

Air is useful as a suit inflation gas but personally I never breathe it underwater. If you have a nitrox cert why wouldn't you use it?

[nigelH]

Most people, once they have become relaxed diving, find the no-stop times of air curtail their dives more than the SPG so nitrox is a benefit.

I only use air when freediving but then I've been know to use a trimix in the pool so I'm no good example.

I'm wondering when the last time I dived on air was so I looked it up and, disregarding three specialist courses (max depth about 5 meters), it was 2003 on holiday in the Red Sea.

[Tunicates]

Er......some one will correct me if I'm wrong ( please! ) but this is my understanding of it.....

The things mentioned above plus:

Its useful if you are planning to be doing three or more dives a day on a liveaboard - longer bottom times, less SI needed, etc.

Its a great way of squeezing a morning dive out the day before flying home from somewhere - depending on O2 loading and other variables - better make sure your Comp is set to 21% for the air diving for the entire holiday so it tracks your O2.

[ShinyD]

To be honest, if you're having to ask the question then you should go back to the book and refresh your memory. Not only on the benefits of Nitrox, but also - more importantly - on the limitations.

I use it all the time - even on shallow bimbles at Swanage. Anything that safely reduces nitrogen loading and hence increases the safety margin has to be a good thing.

There is a theory that micro bubbles play a part in people feeling tired after diving air and that those on nitrox don't suffer the same tiredness. I did see this 'in action' last year when going along to a BBQ that TerryH and his club had in the New Forest following a days diving. Those that were on air during the dive were wiped and falling asleep by early evening. Those that were on Nitrox were fine.

As I say, there are pros and cons, but if you really don't remember the pros then the cons may need refreshing too, so dig your book out

[scuba steve irl]

he did mention iin relation to sport divin .

when divin with air the biggest factor we are concerned with are partial pressure of nitrogen and time . (depth and time)

if the ppn is reduced and when still divin on air tables "as i said above " there are greater safty margins .

oxtox is another issue that we have to consider . once mod's and times are observed no major problem .

o2 narcosis ?????????

for sport diving this is the gas of choice . for deeper depth which the op stated he was not interested in. different gases are a better choice .

so imho your reply was in need of a hug

[scuba steve irl]

Originally Posted by ShinyD

To be honest, if you're having to ask the question then you should go back to the book and refresh your memory. Not only on the benefits of Nitrox, but also - more importantly - on the limitations.

I use it all the time - even on shallow bimbles at Swanage. Anything that safely reduces nitrogen loading and hence increases the safety margin has to be a good thing.

There is a theory that micro bubbles play a part in people feeling tired after diving air and that those on nitrox don't suffer the same tiredness. I did see this 'in action' last year when going along to a BBQ that TerryH and his club had in the New Forest following a days diving. Those that were on air during the dive were wiped and falling asleep by early evening. Those that were on Nitrox were fine.

As I say, there are pros and cons, but if you really don't remember the pros then the cons may need refreshing too, so dig your book out

or just do a refesher course . ya have to understand the gas if your gonna start using it .

[Garf]

Originally Posted by scuba steve irl

he did mention iin relation to sport divin .

when divin with air the biggest factor we are concerned with are partial pressure of nitrogen and time . (depth and time)

if the ppn is reduced and when still divin on air tables "as i said above " there are greater safty margins .

oxtox is another issue that we have to consider . once mod's and times are observed no major problem .

o2 narcosis ?????????

for sport diving this is the gas of choice . for deeper depth which the op stated he was not interested in. different gases are a better choice .

so imho your reply was in need of a hug

ok, you actually said "within its depth limits" and not "within air limits". the difference is critical, especially if you are advising someone who appears to be rusty or unfamiliar with it use. You can either use nitrox with air tables and recieve a benefit in terms of reduced nitrogen loading, or you can use nitrox with nitrox tables, and recieve a benefit in terms of increased bottom time.

As for Oxygen Narcosis, many people believe Oxygen is even more narcotic than nitrogen. A search on here for Meyer Overton Hypothesis on lipid solubility will give you plenty of reading material if you are interested. If you accept that Oxygen is narcotic then you accept that Nitrox offers no benefit in terms of narcosis. Of course, not everyone accepts this and no-one has ever proven it either way. With this in mind, many people simply take the safe option and assume nitrox is just as narcotic as air.