Metric versus Imperial System for Diving?

[dfx]

You know what's gonna happen? The US is gonna adopt SI eventually, and Mike here will claim that they've invented it. Mark my words.

 

[RJP]

 

[mrdre]

Indeed. And counting by threes isn't very "intuitive ".

Why can't we go 5 10 15 20? I'd assume if everybody would use metric then there will be no need to "match" any other system.

OK, besides switching to metric system completely. Of course a person who grew up measuring everything in inches and feet will be doing that practically the rest of his life. Even if you force him to switch to metric he will be dividing meters by 3, multiplying centimeters by 2.5, and dividing kilograms by 2, which will be inconvenient.. Fine.. understandable. But why not use bars? Why cling to PSI? You can't "visualize" pressure right? It's just a number on a gauge. You teach the new diver either bar or PSI - it will be no difference. Right? Although measuring everything in bars gives one cool advantage - it's roughly an atmosphere. Why not use bars with imperial system?

 

[RJP]

Why can't we go 5 10 15 20? I'd assume if everybody would use metric then there will be no need to "match" any other system.

OK, besides switching to metric system completely. Of course a person who grew up measuring everything in inches and feet will be doing that practically the rest of his life. Even if you force him to switch to metric he will be dividing meters by 3, multiplying centimeters by 2.5, and dividing kilograms by 2, which will be inconvenient.. Fine.. understandable. But why not use bars? Why cling to PSI? You can't "visualize" pressure right? It's just a number on a gauge. You teach the new diver either bar or PSI - it will be no difference. Right? Although measuring everything in bars gives one cool advantage - it's roughly an atmosphere. Why not use bars with imperial system?

Interestingly I switched my computer to metric before entering the water for an 85min dive today... and didn't notice a difference at all. Dive wasn't any easier. My buddy - whose computer was set to imperial - and I still turned the dive at a half tank. Craziest thing, though... my half-tank in bar was the same as his half-tank in PSI.

 

[dfx]

Interestingly I switched my computer to metric before entering the water for an 85min dive today... and didn't notice a difference at all. Dive wasn't any easier. My buddy - whose computer was set to imperial - and I still turned the dive at a half tank. Craziest thing, though... my half-tank in bar was the same as his half-tank in PSI.

Until you want to do something useful with the measured values... like do some calculations... as has been mentioned dozens of times before in this thread...

 

[mrdre]

Interestingly I switched my computer to metric before entering the water for an 85min dive today... and didn't notice a difference at all. Dive wasn't any easier. My buddy - whose computer was set to imperial - and I still turned the dive at a half tank. Craziest thing, though... my half-tank in bar was the same as his half-tank in PSI.

But it wasn't any harder either, right?

That's the whole point. There is absolutely no problem using both systems, or switching in between. With only one little difference: (only IF you have to do some calculations) metric would save some divisions and multiplications by some awkward numbers, just because it's decimal. Other than that, there is really no difference in terms of being "harder" or "easier".

 

[RJP]

Other than that, there is really no difference in terms of being "harder" or "easier".

It's objectively quantifiable! (Or was that quantifiably objectionable... ?)

 

[DaleC]

If your argument is that you can't make diving calculations with imperial values the problem lies with you. The math is not that hard. I can understand that you may feel metric is easier, for you. That's a personal opinion. It isn't however, a fact. Even if you mention it dozens of times it still does not become a fact.

That's because "easier" is a relative term relating to both a process and a user. The "easiness" depends on how those two interplay.

 

[RJP]

Until you want to do something useful with the measured values... like do some calculations... as has been mentioned dozens of times before in this thread...

I planned the dive "in metric" on V-Planner... which didn't seem to be any faster or easier than when I had it set to imperial units.

 

[dfx]

If your argument is that you can't make diving calculations with imperial values the problem lies with you. The math is not that hard. I can understand that you may feel metric is easier, for you. That's a personal opinion. It isn't however, a fact. Even if you mention it dozens of times it still does not become a fact.

That's because "easier" is a relative term relating to both a process and a user. The "easiness" depends on how those two interplay.

Please demonstrate how converting from feet of depth to PSI of pressure is easier or at least equally easy than/as converting from metres of depth to bars/atmospheres of pressure.
Please demonstrate how converting from ft³ of volume in water to pounds of lift is easier or at least equally easy than/as converting from litres of volume in water to kilograms/Newtons of lift.