Should I go Full Metric from the Start ?

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the only metric unit I can't "think" in is temperature, it's a complete mind **** for me. I'm bilingual in length, pressure, etc. being an engineer, but I just can't wrap my head around celcius because it's not something I use all the time

Temperatures (at least between 0-100F) work for me in either scale. I do have trouble, however, visualizing bars, and larger quantities of kilometers and kilograms. No doubt that metric is superior in every aspect, but I'll always prefer imperial for diving simply because it is intuitive for me to visualize.
 
If you dive in the Caribbean you will be talking imperial.

The dive op I dove with in Playa Del Carmen and Cozumel used metric.

Mostly - the 2Kg weights i was handed were labelled 4lbs by the manufacturer.

More interesting was the DM showing us the sign for the local fish. "For this fish the sign is <demo> but I might do this <Completely different demo> because that's the sign in French"

For me in Canada my computer is set to Metres and Celcius, my SPG is in PSI, my tank is cubic feet and I measure my lead in pounds, but record visibility in my logbook in feet.
 
The dive op I dove with in Playa Del Carmen and Cozumel used metric.

Mostly - the 2Kg weights i was handed were labelled 4lbs by the manufacturer.

More interesting was the DM showing us the sign for the local fish. "For this fish the sign is <demo> but I might do this <Completely different demo> because that's the sign in French"

For me in Canada my computer is set to Metres and Celcius, my SPG is in PSI, my tank is cubic feet and I measure my lead in pounds, but record visibility in my logbook in feet.

I must say, as a Canadian who dives, my measurements are all messed up. I know how air temperature feels in Celsius only, but I "understand" how water temperature feels in Fahrenheit. I've mainly used PSI in SPGs except once diving the cenotes. For my weight and height, I only know them in imperial. For weights in general, I personally use imperial and metric is unfamiliar to me. But for length and distance, metric is more familiar to me. I suppose it's a matter of being taught one thing in school, and coupled with being so close to the US.
 
the only metric unit I can't "think" in is temperature, it's a complete mind **** for me. I'm bilingual in length, pressure, etc. being an engineer, but I just can't wrap my head around celcius because it's not something I use all the time
How I did it at first was to relate round numbers--ie. 60F=16C, 50F=10C. Gets a little trickier when you get into the "minus". -17F=0C. -40F equals-40C ALMOST exactly. Then it goes the other way. Same idea when going miles to kilometres. After a (long) while you don't have the need to "transpose".
 
You can get SPG's that read in both

I've heard of these elusive dual SPGs, but cannot find any for sale today. Does anyone know a source?
 
I was certified OW and Advanced twenty years and did about 30 dives but then stopped diving. I am starting back again and have projects to do a GUE Fundamental Skills course very soon.

I downloaded the course materiel and started doing the gas management exercices. I have been doing a lot of supplementary reading also. Comparing the Metric and Imperial systems, it appears the Metric is much more simple and intuitive for all aspects of dive planning.

I am thinking of going Full Metric and for instance buying a SPG that reads in Bars instead of PSI.

I live in Montreal, Quebec, Canada, and I realize that probably most potential buddies around me will still be using the Imperial system.

Any thoughts and comments about me taking this route ?
If you understand the GUE gas management material better, then stay with Metric from the the start. . . especially if you plan to travel & dive overseas internationally where you find mostly European & Asian Dive Buddies.

Here are some practical Imperial US/Metric Conversions which you will use a lot:

1 cubic foot is 28.3 liters.

1 lb is approx half a kilogram; (1 kilogram is actually 2.2 lbs).

2 inches is approx 5 centimeters (1 inch is actually 2.54 centimeters);
4 inches is approx 10 centimeters;
so 12 inches (1 foot) is approx 30 centimeters.

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Your common counting numbers, or Reference Cardinal Numbers, for depth seen on most Dive Tables are:

Imperial US (feet) by 10's:
Ex): 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 etc

Metric System goes by 3's:
Ex): 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33 etc

Now note the depth conversion factors above ("3/10" and "10/3") between the two number sequences. . .

So Depth in Meters multiplied by 10/3 gives Depth in Feet;
Feet multiplied by 3/10 gives Meters.
Example: 18m x (10/3) = 60ft; 60ft x (3/10) = 18m.

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Pressure Bar multiplied by 3/2, and multiplied again by 10 gives Pressure PSI;
Pressure PSI multiplied by 2/3, and divided by 10 gives Pressure Bar.
Ex): 200bar x (3/2) x 10 = 3000psi ; (3000psi x 2/3) ÷ 10 = 200bar.

-------
Ambient Air Temperature Range in degrees Celsius that most of us are comfortable in is from 20 to 25 deg C. To convert to degrees Fahrenheit, just double the Celsius value and add 30 (a rough but fair approximation for this temperature range as well as for tolerable water temperatures in the appropriate exposure suit within, above and below this range). So for example 20 deg C is roughly 70 deg F.
 
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the only metric unit I can't "think" in is temperature, it's a complete mind **** for me. I'm bilingual in length, pressure, etc. being an engineer, but I just can't wrap my head around celcius because it's not something I use all the time
For relating to a simple temperature conversion, again think about the habitable or "comfortable/preferable" ambient air temp range of 70 to 80 deg F (just like the average temperature year round here in Southern California) --subtract 30 and take half to convert this to an approximate range of 20 to 25 deg C. (Where this simple relation fails in accuracy is way outside this range of habitability).

Temperatures (at least between 0-100F) work for me in either scale. I do have trouble, however, visualizing bars, and larger quantities of kilometers and kilograms. No doubt that metric is superior in every aspect, but I'll always prefer imperial for diving simply because it is intuitive for me to visualize.
1 atmosphere = 1.01 bar, so for all practical purposes, a surface pressure of 1 atm is 1 bar.

The common AL80 tank has a metric cylinder rating factor of 11 liters/bar, or in other words, at the surface of 1 bar, if you pour water into the cylinder, the measured volume it can contain is 11 liters.

However when pressurized to any value up to its recommended Service Rating (207 bar for the AL80 tank/11L per bar cylinder in this example ), a cylinder carries an equivalent volume of free gas much greater than its water capacity, because the gas is compressed to several hundred times atmospheric pressure (while water is incompressible). So if you have a gas pressure reading of 200 bar in your AL80 tank, you have a total free gas volume of 200 bar times 11 liters/bar or 2200 liters.

15 kilograms -->about the weight of an empty AL80 tank without the valve.

1 kilometer is roughly 6/10 of a mile; in clear weather and calm sea conditions, the horizon is approx at 5 kilometers or 3 miles.
 
@Kevrumbo, I have no trouble doing the conversions in my head. Regardless, I always have to do the conversions from metric to imperial to "visualize" the actual units. Curse the U.S. for raising me in an imperial world! :mad:
 

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