Freeflow at 140'

[Web Monkey]

Maybe you can tell me why I shouldn't hang a tank at 15', I have a reg in the shop how getting O2 cleaned for just that reason.

Because you and the tank might not meet each other.

Call me paranoid, but if it's not hanging off of me somewhere, I don't belive it exists.

Terry


Terry

 

[HappyFunBoater]

Because you and the tank might not meet each other.

Call me paranoid, but if it's not hanging off of me somewhere, I don't belive it exists.

But isn't that similar to attaching a life raft to your BC because you don't trust the boat to be there when you get back?

It seems that a lot of these threads degenerate into discussing a backup for a backup for a backup for a backup, but never trust your backup, so have another backup. When I dive I want to be as safe as is REASONABLY possible, but it's only reasonable to expect a certain number of failures to occur.

In the case of the tank hanging at 15ft', the only reason you're using it is because you've had multiple failures at depth. Not being able to find the tank, and presumably the boat it's hanging from, is just yet another failure. But that doesn't mean that the tank is a bad thing.

 

[Scuba_Steve]

Not a bad thing, but as has been said, gas is pretty much a primary concern, and you never plan on using a gas you're not carrying.

A little bit different than not trusting that your happy-boat will not be there, but then again, we have a plan for that too, it just happens to not be 'carry a spare boat on you'

 

[TheRedHead]

But isn't that similar to attaching a life raft to your BC because you don't trust the boat to be there when you get back?

When you use 100% O2 on a dive it becomes a technical dive and the rules change. You have to account for losing your deco gas. You can't make an escape to the surface. In very cold water, people do plan for a lost boat. Otherwise, they could freeze to death.

You have to understand that people are diving in many conditions and their POV reflects that. It's hard to see that when you're new here because of the sometimes aggressive manner is which opinons are stated.

 

[HappyFunBoater]

...the sometimes aggressive manner is which opinons are stated.

That's an understatement.

 

[JEScholz]

What I have seen in this thread is a number of people who not only think thier way is the best way, but the only way!

 

[lamont]

What I have seen in this thread is a number of people who not only think thier way is the best way, but the only way!

My way is not the only way. But it is a way which tends to eliminate the need for adrenalin and lightning-fast life-or-death decisions. Shutting down a regulator and calmly switching to your backup reg while you've got tons of gas for the depth you are at makes for substantially more boring stories...

 

[MikeFerrara]

But isn't that similar to attaching a life raft to your BC because you don't trust the boat to be there when you get back?

It seems that a lot of these threads degenerate into discussing a backup for a backup for a backup for a backup, but never trust your backup, so have another backup. When I dive I want to be as safe as is REASONABLY possible, but it's only reasonable to expect a certain number of failures to occur.

In the case of the tank hanging at 15ft', the only reason you're using it is because you've had multiple failures at depth. Not being able to find the tank, and presumably the boat it's hanging from, is just yet another failure. But that doesn't mean that the tank is a bad thing.

Why do you say that it's for multiple failures? In OW, having to surface away from the entry point is always a very real possibility. If you expect to need the gas, you carry it with you. It's as simple as that. It's not a backup for a backup. It's simply the gas that we plan on using (bottom and deco) and reasonable and customary contingincy gas.

The recreational agencies teach this hang tank nonsense because they don't teach you how to calculate a turn/ascent pressure and they expect that there will be times that you get to your safety stop short on gas.

 

[HappyFunBoater]

Why do you say that it's for multiple failures? In OW, having to surface away from the entry point is always a very real possibility. If you expect to need the gas, you carry it with you. It's as simple as that. It's not a backup for a backup. It's simply the gas that we plan on using (bottom and deco) and reasonable and customary contingincy gas.

The recreational agencies teach this hang tank nonsense because they don't teach you how to calculate a turn/ascent pressure and they expect that there will be times that you get to your safety stop short on gas.

I thought the purpose of the hanging tank was if you ran out of air. But perhaps I misunderstood the poster's point. It sounds like you're talking about the tank being there for a pre-determined decompression stop. If so, I agree that you shouldn't count on finding the tank. Sorry for the confusion.

BTW, if this tank was meant for a decompression stop, isn't 15 ft a little shallow?

 

[TheRedHead]

BTW, if this tank was meant for a decompression stop, isn't 15 ft a little shallow?

When you have a regulator "O2 cleaned" it's usually for 100% O2. Some divers O2 clean their regs for 50% as well. Either one of these are deco gasses. 20-10 feet is the proper range for using 100% O2. That doesn't mean the diver hasn't previously made deco stops with another gas he/she may be carrying.