max depth with standard air

[Groundhog246]

I like helium.

Watching a TV show on Discovery a couple of days ago and they made the statement that the world is running low on helium and may run out as early as 2010. I don't recall what show and it seems a little far fetched, but what if?

 

[Scuba_Vixen]

"I don't see the gas costs being prohibative compare to the other costs of technical diving."

There's an old expression, something to the effect, "It ain't cheap to run with the big dogs" .... And tech diving is the perfect example. Each increase in depth, or penetration distance gets exponentioally more expensive, both in training and equipment.

Part of tech training is to instill a proper mindset. Part of that is to set a realistic limit for yourself and not exceed it without and untill you have proper gear and training.

Diving is Not an inexpensive endeavor ..... Diving Safely, at or beyond 120', or for longer than NDL times, makes the initial cost of recreational training and gear pale by comparison.

Once you get down there, it'a so easy to drop another 10, .. 20 ... 30 feet ... just to "check it out" .. and after a few times, it's 10, 20, 30 feet past the last time. Deep air is strangely addictive. ... But that could be another thread in itself.

Bottom Line: Don't try to run with the big dogs when you're on a short lea$h ... it'll get you hurt. ... Wait untill you can do it right.

Darlene

 

[MikeFerrara]

Watching a TV show on Discovery a couple of days ago and they made the statement that the world is running low on helium and may run out as early as 2010. I don't recall what show and it seems a little far fetched, but what if?

You can't use what you don't have.

There are just some dives that I won't be doing without it.

 

[String]

You can't use what you don't have.

There are just some dives that I won't be doing without it.

I know of some people that end up paying up to £30 for a trimix fill (twins).
Compare that to the £2 fill for air and thats a huge % more expensive.

Its near 3 times what i pay for a days boat diving on the club boat and 1/3 more what id pay on a charter.

Including fills and boat use i can expect to pay £16 a day on our club boat for 2 dives.

Contrast that with a possible trimix dive and that cost will be near £50.

Thats a large difference in cost and in reality means fewer dives can be done per year on a budget.

I freely admit there are many dives and depths which air is just about impossible to use - Anything 55m or less however is fair game due to the economics.

Technical diving by its nature is far more expensive than "recreational" diving so even though the risk maybe slightly higher any dive that doesnt require technical equipment (ie mix in this case) can be done cheaper without it.

--

As for helium running out, there is a worry - its mined and supplies are running thin, the cost of helium has already risen a fair amount and is set to continue to rise it becomes harder and more expensive to produce.

 

[Travis*N]

Thanks everyone for the replies. So i gather these deep dives are possible, but not a smart thing to do. Another reason I asked is someone I work with told me about the time he tried to set a personal depth record (on air), and went down to about 200', where he said his peripheral vision just started to fade away to a small point and then "sparks" started flying around in front of his eyes........beginnings of 0x-tox??

 

[IndigoBlue]

Watching a TV show on Discovery a couple of days ago and they made the statement that the world is running low on helium and may run out as early as 2010. I don't recall what show and it seems a little far fetched, but what if?

When we eventually run out of helium, there will be a migration towards neon for trimix. Neon does not conduct heat as much as helium, which is good, but it is slightly more narcotic than helium, which does not matter much. Neon will cost much more than helium, since its primary source is only from fractional distillation of air, whereas helium is obtained from underground deposits. Then you will probably see divers routinely moving back to 150 ft to 170 ft diving on air mixes.

Any diving beyond 170 ft without helium (or neon) is quite dangerous, since you are now approaching the 1.4 PO2 limit of oxygen (187 ft) and your PN2 at 170 ft is about 4.9 which is way beyond the 3.0 ATAs that most people find comfortable. The only excuse for diving that deep with that much narcosis exposure would be to externally survey a shipwreck. But with that much narcosis, you are not likely to remember what you saw, anyway.

So either way you look at it, diving deep (over 100ft) on air does not accomplish anything.

 

[String]

So either way you look at it, diving deep (over 100ft) on air does not accomplish anything.

Disagree with that totally. Dives below 100ft on air are quite possible and enjoyable and so accomplish exactly what the diver sets out to do - enjoy it.

Most people i know can enjoy a good ship wreck at 120ft and remember it afterwards.

Change the 100ft to 200ft and i maybe more inclinded to agree with you.

 

[Scuba_Vixen]

There are some things we need to rethink relative to trying to do them on a budget, or not at all. Doing anything much past 100', maybe 120', with a single tank of air exponentially increases the risk of serious injury if a problem occurs. Diving to depths greater than I would care to ESA from without a fully redundant air source is on my "no no's" list. I think too many folks look only at the monetary cost when deciding what to do. The folowing statement scares me a bit:

"any dive that doesnt require technical equipment (ie mix in this case) can be done cheaper without it."

The scarey part is the definition of "require", it seems quite subjective ..... There are some who would say that since they can go to 200' and return on a single al80, that tech gear isn't required.... so why bother with the expense of it...

The real cost of cutting corners on gear/training, is that it can get you hurt or killed, ... and you don't get a second chance to do it right ..... Think about it... if you're already on a budget, what are the odds that you have enough of the proper insurance to provide for your family if you sell the farm down there... If you accept the added risk to yourself, have you provided for your family, since you Also accepted the additional risk for them as well... There is NO, "ooops, sweety, I screwed up, I'll make it up to you".

Diving is a lifetime of enjoyment, good planning and patience insure plenty of both.

Darlene

 

[String]

Depends what you class as "technical". I dont class a twinset or pony cylinder as technical - both are firmly under my definition as recreational diving and arent that expensive. Yes if going deep with deco obligations a redundant air source is advisable. What depth that is and so on you choose based on experience and risk youre willing to take. The issue here was very deep air. As i said, personally i wouldnt go below 50m or so on air and id be dubious about going TO 50m. Deeper than that the cost increases near 20x per dive for the gas mix. Some people use trimix for depths of only about 35m. Personally im not willing to pay a vast amount more for a dive im more than happy to perform on air.

 

[pwfletcher]

It really depends on the person. I have a half a martini buzz at 150ft (hardly noticeable) and a full martini buzz at 185ft (my limit on air ... but not at a party). I know other instructors on this board that start to feel narced at 100ft. At whatever point you feel that you are not in control, you better ascend or risk the long deep sleep. However, the risk is mine to take ... I don't want someone else telling me that I can't go deeper than 100ft on air simply because that is their limit. We are all grown ups and can chose for ourselves to accept the risk or to refrain from going deep. There is still alot to see <100ft.

As for helium costs, if you feel that you need the helium at a certain depth, you better bring it with you. Save yourself some money and buy a CCR rebreather ... I can last 10 hours at virtually any depth on a tiny 3 liter bottle. That is approximately 5 two hour dives for $10.