Metric measurements?

[John Bantin]

I wonder how many Scubaboard users are familiar with metric measurements (m, kg, litres, °C, bar, etc)? Obviously, everyone outside of the US now uses metric but how many American divers get it?

 

[Lorenzoid]

John, almost all Americans are exposed to it to some extent in high school science class. And obviously if one pursues a career in the sciences, engineering, healthcare, etc., they will use metric. Also, people who were in grade school in the 1970s like me were indoctrinated in it because the US was on the verge of going metric before chickening out.

Of SB users, who I like to believe as a group have better than average education and involvement or at least interest in scientific things, I would guess most are familiar with metric.

I would gladly use liters and bar exclusively in diving. But what is annoying is having to switch between systems.

 

[Manatee Diver]

I can use them if I need to, and can estimate between the two systems back and forth. Obviously if I am doing something precise I will break out a calculator.

That being said I think the US system of effective tank capacity is better than the European system of water capacity of the tank.

 

[chrisch]

...
That being said I think the US system of effective tank capacity is better than the European system of water capacity of the tank.

Oddly that's the only bit of the Imperial system I cannot get my head round. A meter and a yard are near enough so a meter is three foot and 15psi is atmospheric pressure so one bar (ATM). Submarine pressure is easy in metric but not really really hard in Imperial.

But cubic feet (really?) are just kinda weird.

 

[Storker]

I think the US system of effective tank capacity is better than the European system of water capacity of the tank.

Given that I inherently disagree, care to elaborate? I'd like to learn the POV of those "on the other side"

 

[Marie13]

Very familiar with kg. I work in international shipping and I’m converting between lbs and kgs all day long by hand. I use an online conversion tool for cm and m.

 

[Manatee Diver]

But cubic feet (really?) are just kinda weird.

It is a measurement of volume, just like the liter. It is just under the US scuba labeling scheme we label them by effective capacity.

So you know that a HP100 contains about the same amount of gas as a LP100. Where as under the European labeling they would be labeled as 12L and 15L (IIRC) respectively to find out their effective capacity you would need to find the working pressure and multiple that out.

 

[Lorenzoid]

It is a measurement of volume, just like the liter. It is just under the US scuba labeling scheme we label them by effective capacity.

So you know that a HP100 contains about the same amount of gas as a LP100. Where as under the European labeling they would be labeled as 12L and 15L (IIRC) respectively to find out their effective capacity you would need to find the working pressure and multiple that out.

I understand you were just giving one example (got another?), but as far as that example is concerned, if I significantly overfill my "LP" whatever tank beyond its rated working pressure, which is not uncommon, then I still have to go through the calculation to know how much gas I have. I get the impression that nowadays, with HP tanks being so common and HP fills being more widely available, only people who routinely overfill their LP tanks still prefer them over HP.

 

[Diving Dubai]

Being British I have always been exposed to both in daily use

Inches, feet yards and miles were okay but I much prefer the metric equivalent (I never did memorise how many yards to the mile) Base 10 is much easier

Weight were easy once you learned how to "visualise" a bag of sugar was 2lb now 1kg (2.2lbs)
We have anachronisms. We use miles for distance in cars and mph as a speed, despite using liters for fuel, fuel consumption is miles per (UK) Gallon. Even though I've lived in a fully metric country where we use km's for 10 years I still can't visualize 20l per 100km for fuel consumption - it's meaningless until I convert it to MPG (16) then I realise how thirsty my truck is.

A person's height in feet and inches I can visualise so 5'8 means more to me than 172cm, yet if you told me that a building dimension was X'XX" I'd have to convert it to metre or millimeters visualist it (I rarely use cm)

 

[Diving Dubai]

It is a measurement of volume, just like the liter. It is just under the US scuba labeling scheme we label them by effective capacity.

Yes but calculating consumption is easier

For a 12l tank, 1 bar=12l on a 15l tank, 1 bar=15l, So if you know you're breathing 15l/m at the surface you can easily figure that to be 4bar/m at 30min