Sharing air to extend bottom time

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As a customer, you don't have to accept something that you're not happy about. Attach your regulator, crank a valve.. hey, presto! If it's a low fill, then refuse it... then it's the shop's problem.

I don't see what the issue is here. If you're worried about short fills, then check your tanks before it's too late.

You won't convince me that it is impossible to check a tank before you depart on a boat etc. Just turn up a little early, if necessary... what's the problem?

All part and parcel of being a diligent, well-prepared diver IMHO.
If you go to some locations the tanks will not be stopping by the shop it will be delivered directly to the boat. You will not be allowed onto the deck with the tanks untill the tanks is all loaded up, row call has been made and the boat is off. This is SOP in some areas which means if you wanna dive there, thats what you have to deal with.
If when you set up the gear and check the pressure to find it low, there may or may not be spare tanks available, if its not (which is of course more likely later in the day than early in the day) and you refuse the tank, that means you dont dive.

Of course.... that's all ignoring the point I've been trying to get across - about the use of two tanks for a dive. That solves the issue of low-fills. It solves the problem of insufficient gas for the planned dive, especially where nitrox is used. It solves the problem of redundant gas for emergencies.

Go figure... you argue that insufficient gas is a problem... and then you argue that having extra gas is irrelevant. Not got the logic sorted on this one yet?
Most divers dont have multi-tank setups or the capability of them, which is why multi-tank setups is irrelevant. You think youre going to make it standard practice that all divers carry multiple tanks? Best of luck, but I dont think thats going to be possible.


Ah, ok... so it's just me... a sidemount instructor.... and the majority of agencies - that supply sidemount courses to a rapidly expanding demographic of recreational divers... that don't know what we're talking about? LMAO

The fact is that 90% of 'rec' divers don't even know what 'gas redundancy' or 'gas planning' is - that's an issue. In fact, it is THE issue that started this thread.
I absolutely agree that it is a serious issue that most divers have no clue about gas management and that should be rectified, but I also dont think that reality will be that the average diver - which lets be honest, DONT hang around on scubaboard - will be trained in multi-tank setups, be it backmounted or sidemounted anytime soon, ESPECIALLY with the agency standards being more and more simplified.

As an established contributor to Scubaboard, you are not ignorant of such issues... so why hide behind those issues now, when faced with a solution that defies your debating stance on the 'need' to muddle through dives on a single tank that doesn't hold as much gas as you actually plan for/need?
Im not ignorant of the issues, however I do more diving than I like while travelling (due to boring local sites) and see how much of a mess that can be on a regular basis and what costs it involve to get more tanks, gear and so on when on travel. While I would love all divers to be 100% self-sufficient and all locations to be able to provide whatever gear I feel I need to use, I just dont see that becoming a reality however hard we try.

What 'most divers do' and what 'most diver should do' are two entirely different notions. If there was no discrepency between those two states, then we'd have very few fruitful discussions here on Scubaboard. Are you really going to drag this debate to the lowest common denominator - and suggest that divers should just 'follow the herd' and do what the majority do... even if they know better???

We can help resolve that issue by educating divers about effective and safe solutions to their ignorance.......or we can stick our heads in the sand, use bastardized solutions for eeking out a few extra minutes on a dive and blinker ourselves to what our real options are.

I see you've gone for the latter course of action?
I 100% agree that what most divers do and what most divers should do is two widely different things and that we should try to close that gap, however as far as this discussion goes its about what was observed and I have stated that I do not like the practice of DMs sharing air with guests to extend divetime. I have no issue with trained divers with no other obligations doing it in a safe manner, simply because we SHOULD all be able to share air with no problem. The reason I dont like DMs doing it is the fact that they should not be bound up to one guest and be unable to do their guiding or assist others if needed.

I am NOT sticking my head in the sand and ignoring options, Im simply from what Ive seen with regards to tank supply and management in some locations as well as the lack of training and gear for multi-tank setups in the vast majority of divers of the opinion that at the current time that is NOT a viable option in many locations.
 
If you go to some locations the tanks will not be stopping by the shop it will be delivered directly to the boat. You will not be allowed onto the deck with the tanks untill the tanks is all loaded up, row call has been made and the boat is off. This is SOP in some areas which means if you wanna dive there, thats what you have to deal with.
If when you set up the gear and check the pressure to find it low, there may or may not be spare tanks available, if its not (which is of course more likely later in the day than early in the day) and you refuse the tank, that means you dont dive.

I never saw a decent operation that didn't carry at least one spare tank. In Sharm el Sheikh tanks were loaded on the boat before guests were allowed on- that was SOP, but if you found an empty tank, it was usually pretty simple to swap it for another or give it to the DM :). Some tanks could be 190bar but 10bar shouldn't impact much on a standard 60min dive (which again is SOP). Given that experienced divers normally have a decent SAC, a standard AL80 even at 190 bar should be ample gas for the vast majority of recreational dives, thus not requiring said experienced divers to share air.


I absolutely agree that it is a serious issue that most divers have no clue about gas management and that should be rectified, but I also dont think that reality will be that the average diver - which lets be honest, DONT hang around on scubaboard - will be trained in multi-tank setups, be it backmounted or sidemounted anytime soon, ESPECIALLY with the agency standards being more and more simplified.

The 'average' diver most likely doesn't have the equipment setup or cool head to share air effectively at depth either.
 
I never saw a decent operation that didn't carry at least one spare tank. In Sharm el Sheikh tanks were loaded on the boat before guests were allowed on- that was SOP, but if you found an empty tank, it was usually pretty simple to swap it for another or give it to the DM :). Some tanks could be 190bar but 10bar shouldn't impact much on a standard 60min dive (which again is SOP). Given that experienced divers normally have a decent SAC, a standard AL80 even at 190 bar should be ample gas for the vast majority of recreational dives, thus not requiring said experienced divers to share air.
I have seen it happen down there that theres no extra tanks at the end of the day, but then again the entire boat did 3 dives and thats just not what normally happens. None of the tanks was short filled though so that wasnt a problem.
In sharm you can actually order bigger tanks, smaller tanks, weird mixes and whatnot as well so its not much of an issue there. Dont know if that applies to all ops there though.
Lucky me is going down there for 2 weeks the 17th of june btw :)


The 'average' diver most likely doesn't have the equipment setup or cool head to share air effectively at depth either.
Unfortunately I think thats true :(
I dont think the ones that wont be comfortable with it is the ones that would do it either though, but unfortunately its probably those who might have a DM stick a reg in their mouth when they start running low on air :(


Mr Carcharodon, my Impression is that its not generally "the average" diver who hang around on scubaboard..
 
The 'average' diver most likely doesn't have the equipment setup or cool head to share air effectively at depth either.

OK, at this point you are descending into hysteria.
 
OK, at this point you are descending into hysteria.
Unfortunately Ive seen a fair share of divers signalling 80 bar and then starting to frantically make their way to the surface in a fairly distressed manner with no regards of what may or may not be above them :(
 
If you go to some locations the tanks will not be stopping by the shop it will be delivered directly to the boat. You will not be allowed onto the deck with the tanks untill the tanks is all loaded up, row call has been made and the boat is off. This is SOP in some areas which means if you wanna dive there, thats what you have to deal with.
If when you set up the gear and check the pressure to find it low, there may or may not be spare tanks available, if its not (which is of course more likely later in the day than early in the day) and you refuse the tank, that means you dont dive.

Ring ahead - tell them you want to check your tanks before loading. That's especially valid if you've ever received a low-fill from that operator.

OR

Get on the boat, check your tanks immediately, whilst everyone else is chatting and wasting time.

OR OR OR....

...a hundred other solutions, requiring only the slightest amount of initiative, to ensure you don't waste a day's diving.

OR... sign up for a 2-day recreational sidemount class, which any OW diver can do... where you end the problem once and for all.

Most divers dont have multi-tank setups or the capability of them, which is why multi-tank setups is irrelevant.

Which is why the agencies created and are promoting sidemount training...

As of 2012, any Open Water Diver or above, now has access to training on a multi-tank capability...along with some other seriously beneficial skills and drills.

Nice... isn't it? :)

You think youre going to make it standard practice that all divers carry multiple tanks? Best of luck, but I dont think thats going to be possible.

Nope - not a standard practice for all. Just for those who don't like having dives cut short due to air-consumption or the risk of short-fills.... or those who want gas redundancy for other reasons.

I absolutely agree that it is a serious issue that most divers have no clue about gas management and that should be rectified, but I also dont think that reality will be that the average diver - which lets be honest, DONT hang around on scubaboard - will be trained in multi-tank setups, be it backmounted or sidemounted anytime soon, ESPECIALLY with the agency standards being more and more simplified.

Let's just see how sidemount gets popularized shall we? It has the full weight of PADI now...

As for "standards being more and more simplified".... have you seen the extent of training provided on a rec sidemount course yet?

Available for OW divers... it is significantly skill-based.... and extremely beneficial, especially compared to most other specialties or the AOW course...


what costs it involve to get more tanks, gear and so on when on travel.

On sidemount: I go for a 2-tank dive trip. I get 2x AL80s. Those tanks last for two dives. I get redundancy and more practical reserve on both dives.

You DO understand how that works, don't you?

While I would love all divers to be 100% self-sufficient and all locations to be able to provide whatever gear I feel I need to use, I just dont see that becoming a reality however hard we try.

Who cares about the herd? Care about yourself.

If YOU need more gas for a dive - then there is a solution for that. It doesn't require 'extra' tanks over the space of a day. It does require some (very good) training, available immediately after entry-level.

The kit requirement is an approximately investment to buying a regular BCD... and cheaper than using back-mounted doubles.

I have no issue with trained divers with no other obligations doing it in a safe manner, simply because we SHOULD all be able to share air with no problem.

We SHOULD be able to share air for an emergency ascent. THAT is what we are taught - nothing more, nothing less.

We SHOULD plan our dives and dive our plans. The 'textbook' response is to plan dives that account for our air consumption and air supply - not to bastardize an emergency technique so as to fudge the consumption-versus-supply relationship.

We SHOULD ensure sufficient personal gas for the dive we plan to conduct. That remains the OPTIMUM solution - and one that is now available to any diver.

I am NOT sticking my head in the sand and ignoring options, Im simply from what Ive seen with regards to tank supply and management in some locations as well as the lack of training and gear for multi-tank setups in the vast majority of divers of the opinion that at the current time that is NOT a viable option in many locations.

You are saying that sidemount training is irrelevant. Yet you base your debate on the fact that divers lack training and gear for multi-tank diving.

FACTS:

1. Any Open Water Diver can undertake Sidemount training...it is quicker and less expensive than the average AOW course.
2. Sidemount kit comparative in price and availability to back-mount singles kit
3. There is nothing 'technical' about diving sidemount - only those who've never dived it believe that, due to incorrect assumptions
4. A sidemount trained diver can go to ANY dive operation in ANY location and use ANY available cylinders to conduct ANY dive.
5. Diving sidemount effectively negates any issues over gas supply, air consumption and gas redundancy.

With all due respect, what 'you've seen' is irrelevant. You go on holiday, where you see a herd of holiday divers, doing holiday dives. They are neither the 'model' for good diving, nor representative of the full spectrum of capabilities at their disposal.

You didn't see a sidemount diver yet... no wonder, the course was only released by PADI this year. But it IS released, and it IS an option NOW.

I don't doubt that most of the herd won't be rushing to find a sidemount instructor... as we both know, they care nothing about gas management, consumption or anything else beyond 'going down and seeing fishes'... hoping to be 'back on the boat with 500psi'. However, for those who do care - there are solutions... some optimal... some bastardized and unsanctioned improvisations. Let's worry about those who do care....
 
OK, at this point you are descending into hysteria.

I don't quite what you read to be hysterical. Maybe I need to make myself clearer and this time I will put on my professional cap. I am in an excellent position to see the 'average' diver on vacation.

There are not that many vacationing divers who come equipped with long hoses to share air in a comfortable or safe manner at depth to extend bottom time. There are not many that have the understanding of gas management to share air in a safe manner at depth. This is what I see week in and week out.
 
Personally I dont need more air (normally), and if I do I get a bigger thank. If I cant get a bigger tank, I just dont do it.
Yes, its nice that everyone can get sidemount training and that PADI support it (they are afterall the big fish), but that alone I dont think will make it "common practice" anytime soon, unfortunately. Personally Im kinda itching for some new things myself but then again, Im a scubaboard diver and has come to realize that makes me a bit more dedicated than average.
I DO like the fact that sidemount can be done with any given tank and not just "whatever fits into your gear" and I think that might hold a big advantage over backmount?

I have to clarify that when I said standards get simplified Im referring to basic training and NOT specialty courses, like the self reliant diver that didnt even exist not long ago and now the sidemount course. Unfortunately many divers is going to take only what they need to take in order to dive wherever theire on vacation though and as such cutting the standards on the basic training isnt all that great. Its not that it takes too long or cost to much as it currently is.

I dont think sidemount training (or backmount or pony for that matter) by itself is irrelevant, but I think its irrelevant in this particular discussion, due to the fact that most divers dont have the gear or the training for it.
 

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