overfilled tank capacity?

[Packhorse]

Right, but while we can look at most tanks and see exactly how much air will be in a full one, you have to know it's size (which isn't stamped on it), and it's pressure rating to find out how much air it holds. Bah...

Sorry but you are wrong.
The size of the tank IS stamped on it. Perhaps you missed the part of my previous post that stated "Here we rate tanks in WC " "Your tank is stamped with its WC rating"
You have obliviously not seen a metric rated tank before. So I can understand your ignorance.

 

[Packhorse]

.

 

[dannobee]

Maybe in other countries, but I think the original poster is in the US. Tanks here don't always have the size stamped on them. Other info like exemption numbers/dot/serial numbers and hydros, but not tank capacity.

Sorry but you are wrong.
The size of the tank IS stamped on it. Perhaps you missed the part of my previous post that stated "Here we rate tanks in WC " "Your tank is stamped with its WC rating"
You have obliviously not seen a metric rated tank before. So I can understand your ignorance.

 

[cmalinowski]

Ahh how I love the metric system.
Here we rate tanks in WC (water capacity) in Litres or Kgs (same thing as 1 litre of water weighs 1kg).
So a 10 L tank with 230 bar of pressure = 2300 liters
If your SPG says 65 bar then 65x 10L=650 liters of gas left.
If you used 150 bar or pressure during your dive you used 150bar x 10Liters= 1500 liters.
We dont bother with all this + rating BS. Your tank is stamped with its WC rating and its WP or CP rating (working pressure or contents pressure). As far as I know you can not buy LPs new. 207bar and 232bar and 240 bar tanks are then most common, although the OSH limit for scuba tanks is 227bar.

Oh, so we're getting into the my country is better than your country debate, huh? Well, don't go too far or I'll tell my president that you tried to kill his daddy. Next thing you know, NZ will be "the" hot bed of al qaida

Sorry, couldn't resist.

Yes, metric is better for diving. Calcs are easier. But my pea-sized brain has difficulty with conversion. I think I'll need to live abroad for a few years to get it down

Chris

 

[all4scuba05]

strange how our medical world here in the US follows the metric system.

 

[Luis H]

Ahh how I love the metric system.
Here we rate tanks in WC (water capacity) in Litres or Kgs (same thing as 1 litre of water weighs 1kg).
So a 10 L tank with 230 bar of pressure = 2300 liters
If your SPG says 65 bar then 65x 10L=650 liters of gas left.
If you used 150 bar or pressure during your dive you used 150bar x 10Liters= 1500 liters.
We dont bother with all this + rating BS. Your tank is stamped with its WC rating and its WP or CP rating (working pressure or contents pressure). As far as I know you can not buy LPs new. 207bar and 232bar and 240 bar tanks are then most common, although the OSH limit for scuba tanks is 227bar.

The real problem with the metric system is that it is to easy to do calculations with it. Keeping the imperial system with all kinds of non-compatible units opens the doors for new specialty courses, like how to calculate your air consumption. I bet there are plenty of suckers, I mean customers, that would sign up for that one. :itwisted:

 

[Packhorse]

Oh, so we're getting into the my country is better than your country debate, huh? Well, don't go too far or I'll tell my president that you tried to kill his daddy. Next thing you know, NZ will be "the" hot bed of al qaida

Sorry, couldn't resist.

Yes, metric is better for diving. Calcs are easier. But my pea-sized brain has difficulty with conversion. I think I'll need to live abroad for a few years to get it down

Chris

Not sure about Al quaida. But the last terrorists we had here created a lovely diving experiance. Shame someone had to die

http://www.divenorth.co.nz/

Oh and of course NZ is better than the US. We have the same amount of coastline and less divers!

 

[pescador775]

The US has been a leader in bizarre regs or laws such as mandating air bags which cost 100 million dollars for each life saved. However, the euros and Australians caught up and passed America. Ever wonder why some of these countries require yearly hydros and are moving towards a "drivers license" for divers? One reason, Australian regulations are proposed, formulated and written by a private company under contract. These regs have the force of law and since the company makes more profit by writing more regs that's what they get---a police state of nit picking factotums watching and critiquing everything they do. In the US, state laws are heading that way although conservative governments at the federal level have restrained it to some extent. For example, as to state laws, all of them now prohibit the use of running lights while driving. My question is why do the manufacturers even still install the lights (also called "parking lights"). Just for turn signals I guess. In any case, the law makes no sense. In Spain, only runnning lights are allowed in the cities at night. Headlights are prohibited. It doesn't matter who's right, they just pass the regs and have an excuse to arrogantly screw with people's lives 24/7.

Anybody who claims that the + rule and the ratings of Scuba tanks is not deceptive---is being deceptive. We see this behaviour in "fine print" contracts all the time. It is called bait and switch or, more accurately, fraud. With Scuba, this has been going on since at least 1954, when I started. As an instructor, I was discouraged from telling students that a "72" was actually a "65". Play along to get along. To hell with that.

The compressor manufacturers are worse. They actually invented pseudo scientific terms to allow them to exaggerate the output of their machines. You might know what I'm talking about; "SCFM" was high jacked from the scientific community, altered and advertised in a dishonest way. The manufacturers cover their butts by inserting fine print gobble-de- gook to confuse people similar to the guy who started this thread. Here is a case of the devil and his apprentice. The manufacturers not only reference the compressor output to a falsely advertised "80" cu ft tank but specify in fine print that the fill is 500-3000 psi, and therefore a partial fill is used to calculate "SCFM". Moreover, they consider a hot fill to be a complete fill.