Why isn't DIR universally metric?

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Because if they're injured/incapacitated, they may well be using gas at a much higher rate than normal; they may also have lost a considerable amount during whatever caused the problem. If I've got to move them by towing/pushing/pulling, I'd like to have some idea of how long they're likely to be able to go on their own gas (at what may well be a very elevated RMV, more than the nominal 1.0) before I've got to donate mine.

If I am unconcious please just keep a reg in my mouth and screw looking at my SPG. Unconcious people aren't stressed and don't hoover.

you've probably got a lot of more important things to worry about first before worrying about metric vs. imperial.

Ummmm yeah I agree with Lamont, get back to us once you're through Tech1, I have a funny feeling it won't seem so important then.
 
LOL.

Seriously, though. Both systems are rated in volume per pressure. L/bar, CF/PSI. It makes little difference to me.

Well, OK, if I have to be serious, I'll have to agree.

Although, I have to admit, I find tank factors a little more irksome to use, than multiplying bar's by water capacity.
 
Why anyone is still using imerial is beyond me, all I can think of is the old dog new trick thing.
I just bought a Cobra computer and one of the reasons is so that I can switch to metric when I am in Thailand and will not have to make the conversion from psi to bars underwater when telling the DM how much air I have left.

However, the computer on my wrist will still be imperial. Last thing I need the first (next?) time I am narced is to look at my computer, see that I am at 35 and think it is 35 feet when it is actually 35 meters.
 
I just bought a Cobra computer and one of the reasons is so that I can switch to metric when I am in Thailand and will not have to make the conversion from psi to bars underwater when telling the DM how much air I have left.

However, the computer on my wrist will still be imperial. Last thing I need the first (next?) time I am narced is to look at my computer, see that I am at 35 and think it is 35 feet when it is actually 35 meters.

because metric is usually to the tenth of a meter, you'll more likely look at your depth timer and think that you're at 350 feet...
 
Well, OK, if I have to be serious, I'll have to agree.

Although, I have to admit, I find tank factors a little more irksome to use, than multiplying bar's by water capacity.

There are some combinations of pressure and volume that are arguably
easier to compute on the fly with metric gauges. Same is true for Imperial.

A 12L cylinder at oh... 132BAR isn't "easy"

I prefer to work in whatever my gauge reads. Be it PSI or BAR, I know my approximate surface rate of consumption in those units. Without gauges that read volume, I see no particular reason to think of volume at depth. I trust my team to manage their own gas.
 
There are some combinations of pressure and volume that are arguably
easier to compute on the fly with metric gauges. Same is true for Imperial.

A 12L cylinder at oh... 132BAR isn't "easy"

Very true. But I do all such planing before the dive & very little on the fly. (I'm in the wrong bloody forum again aren't I)

I prefer to work in whatever my gauge reads. Be it PSI or BAR, I know my approximate surface rate of consumption in those units. Without gauges that read volume, I see no particular reason to think of volume at depth. I trust my team to manage their own gas.

Yes, once I'm in the water, I too think in terms of pressure & not volume. Yes, I let people manage their own gas as well. I certainly don't police everyones SPG, so don't care what system they use.
 
You would have to be pretty messed up to mix up 35m and 35feet.
It took a few dives to get used to the different numbers for me,
but now it's second nature.
 
I think in terms of pressure as well, and utilize a favorable one-to-one metric pressure to depth relationship.

It just so conveniently turns out that my gas consumed in bar is directly related to the depth I'm at in meters: If I'm at 30m depth in warm tropical waters, then I know I'm going to use up 30bar of gas in 10min. Or if at 45m depth --> 45bar/10min; Or going deep to 60m --> 60bar/10min etc. For nominal finning to hard exertion conditions at a particular depth, I can easily calculate gas consumption figures, on-the-fly in realtime, even before checking & verifying with my SPG.

(Cold water rate is slightly more, but still intuitively just as easy; it's all explained here --
Metric System Math Trick. . . - DIR Explorers)
 
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