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cummings66
03-06-2008, 17:17
OK, here goes.

Reading the ADM E-zine Issue 2 article Diving into the Metric System makes me think a few things.

One, I can do the math much easier when it comes to air consumption, tank pressures left, etc. However right now the metric system is Greek to me. I know what the terms are, I know roughly how they convert to our system, etc. But I do not think in metric which appears to be the point of the article. To be effect you've got to think in metric, so that distance is 40 meters deep for example, not what I'd call 120 feet which is how I'd convert it and I know in reality that it's really deeper than 120 feet, but for visualization that's the number I would choose. To be effective I've got to have a feel that 40 meters is so far, I've got to see it in my mind in those terms to mean anything to me.

They suggest you learn to think native metric system, forget about converting things in other words.

That brings up this question and my concern. Living here in the states I don't know if it's possible to learn to think metric, have you learned to do so and what tricks did you use to help? Do you now think of distances metrically when driving a car, or looking across the yard or do you still convert? Is it even practical for me to think metric?

I see the benefits to diving, it's much easier. I can do the math in my head and be pretty accurate compared to the guesses we do on the fly with our system. Take our tank conversion factors to psi as an example to see how much volume we have at a certain psi in a certain tank. Much easier in metric if I can learn to think metric, but not as easy in our system.

I can do ours from memory, but I use paper and pencil, I think I can learn to do metric without paper and pencil and be more accurate. However, is it practical?

Cojrock
03-06-2008, 18:08
Science is metric so thats the one i use, i dont think it really matter which one you use tho as long as you have a good feel of what it means.

Chad
03-06-2008, 18:16
I wish I had been taught metric more growing up. I am finally decent at eyeballing bolt sizes in metric but I am still not very good at guesstimating weight or volume in metric. I think it is a bad decision to teach US. Imperial measurements in schools as the preferred measurement. Like Cojrock said science is metric.

wgt
03-06-2008, 18:19
OK, here goes.

Reading the ADM E-zine Issue 2 article Diving into the Metric System makes me think a few things.

One, I can do the math much easier when it comes to air consumption, tank pressures left, etc. However right now the metric system is Greek to me. I know what the terms are, I know roughly how they convert to our system, etc. But I do not think in metric which appears to be the point of the article. To be effect you've got to think in metric, so that distance is 40 meters deep for example, not what I'd call 120 feet which is how I'd convert it and I know in reality that it's really deeper than 120 feet, but for visualization that's the number I would choose. To be effective I've got to have a feel that 40 meters is so far, I've got to see it in my mind in those terms to mean anything to me.

They suggest you learn to think native metric system, forget about converting things in other words.

That brings up this question and my concern. Living here in the states I don't know if it's possible to learn to think metric, have you learned to do so and what tricks did you use to help? Do you now think of distances metrically when driving a car, or looking across the yard or do you still convert? Is it even practical for me to think metric?

I see the benefits to diving, it's much easier. I can do the math in my head and be pretty accurate compared to the guesses we do on the fly with our system. Take our tank conversion factors to psi as an example to see how much volume we have at a certain psi in a certain tank. Much easier in metric if I can learn to think metric, but not as easy in our system.

I can do ours from memory, but I use paper and pencil, I think I can learn to do metric without paper and pencil and be more accurate. However, is it practical?

Thinking in metric is no different than thinking in any other system of weights and measures (e.g., the Imperial system, where gallons are bigger than US gallons, etc.). All measures must relate to something familiar, whether physical or temporal. For example, 3 meters is three giant steps or the height of the basketball hoop. 100 km is how far you're likely to travel on the highway in one hour. Water freezes at 0 degrees and boils at 100 degrees. The corals looked happy during my night-dive yesterday and it was 24 degrees. It's also useful to guess how big familiar objects are and then measure them without converting to inches first (Unclepooty should resist the temptation to comment on this point). Then see how close your guess was and whether you improve with practice.

Once you try it a few times, you'll probably think of other imaginatve ways of honing your skills (e.g., how long is the pencil that you use to make your mathematical conversions?). It really is worth it, as the US is the eternal hold-out against the metric system, and travel abroad is greatly facilitated with a comfortable understanding of international weights and measures.

Congratulations on being broad-minded.

texdiveguy
03-06-2008, 18:25
Metric is a great thing particulary for us divers, but you pretty much have to been raised in a metric mind set to catch on, at least for me. I am from a social science background not an engineering or science...so metric except for the basics still is foreign, I for one am sticking to the imperial method.

cummings66
03-06-2008, 18:54
I will say that the arguements for learning it on trips abroad are valid, but I see the ease with which I can computer the things we need to do in diving. It honestly is so much easier that it makes ours look sick. But, I can not picture a distance and know without thinking how far it is.

When I look at a football field I know it's 100 yards, I know that distance. I know the distances such as 25 yards, and 50 yards as well due to gun ranges. I can tell you how many feet that is because I've grown up knowing and doing that.

I want to now do the same with Metric and I find it's extremely tough, it's like learning German IMO. There has got to be a trick to it that I can't think of. I can tell you a person might be 2 meters high, and maybe that will be how I start off. I base vis reports on people so by extension I could learn I think to convert that to meters.

For example, if the vis is just past my arm by about 2 feet I might say the vis is 5 feet, how on Earth would I say that in metric? I mean how would I picture it. I judge the extra 2 feet, see that's the issue. I have to think about what a foot is in metric.

I will learn this, I will learn to think in metric somehow. It honestly is not easy for those of us who live normal working class lives in the states. I know the terms but we just don't have the chance to use them.

PlatypusMan
03-06-2008, 19:15
Most of us here are of a certain age, and probably recall that at one time Congress passed a bill to officially take the US into the metric system of measurement.

It failed miserably--due to the hue and cry of older generations of US citizens who not only disliked the fact that they were no longer using familiar measures, but actively (and in some cases vocally) refused in many instances to utilize it.*

Kids in school were taught metric for about two years, and then the whole thing pretty much fell by the wayside.

I've got to go with cummings66 here, in that if you can learn to think in a system, you can begin to natively utilize that system effectively; the same is true of a foreign language and fluency and comprehension in it.

PPM

*My car gets 40 furlongs to the hogshead, and that's the way I likes it!--Grandpa Simpson

wgt
03-06-2008, 19:29
I will say that the arguements for learning it on trips abroad are valid, but I see the ease with which I can computer the things we need to do in diving. It honestly is so much easier that it makes ours look sick. But, I can not picture a distance and know without thinking how far it is.

When I look at a football field I know it's 100 yards, I know that distance. I know the distances such as 25 yards, and 50 yards as well due to gun ranges. I can tell you how many feet that is because I've grown up knowing and doing that.

I want to now do the same with Metric and I find it's extremely tough, it's like learning German IMO. There has got to be a trick to it that I can't think of. I can tell you a person might be 2 meters high, and maybe that will be how I start off. I base vis reports on people so by extension I could learn I think to convert that to meters.

For example, if the vis is just past my arm by about 2 feet I might say the vis is 5 feet, how on Earth would I say that in metric? I mean how would I picture it. I judge the extra 2 feet, see that's the issue. I have to think about what a foot is in metric.

I will learn this, I will learn to think in metric somehow. It honestly is not easy for those of us who live normal working class lives in the states. I know the terms but we just don't have the chance to use them.

You're actually off to a great start Cummings. Don't get discouraged. Start with rough measures. If viz is near the end of your reach, calling the viz at a bit less than a meter is good enough. If it's an arm's length past your hand, call it a meter and a half. Again, that's close enough to get the hang of it. As the distances get longer, increase the significant units. If viz is about 100 feet, American divers will make estimates of 90 - 100 feet or 100 - 120 feet. It's the same with metric, except you have to get used to meaningful ranges given the distances that you're dealing with. In warm-water diving, a 3-meter resolution is pretty darn good, so don't be afraid to make some booboos. That's how you learn.

hoobascooba
03-06-2008, 20:31
I want to now do the same with Metric and I find it's extremely tough, it's like learning German IMO. There has got to be a trick to it that I can't think of. I can tell you a person might be 2 meters high, and maybe that will be how I start off. I base vis reports on people so by extension I could learn I think to convert that to meters.

For example, if the vis is just past my arm by about 2 feet I might say the vis is 5 feet, how on Earth would I say that in metric? I mean how would I picture it. I judge the extra 2 feet, see that's the issue. I have to think about what a foot is in metric.

I will learn this, I will learn to think in metric somehow. It honestly is not easy for those of us who live normal working class lives in the states. I know the terms but we just don't have the chance to use them.

hey man, it is ALOT like learning German - I know - I've learned German. Lived there though, so I was immersed in it. I had to learn to think in German, not in english (and for those of you who've never learned a second or third language, you probably don't know what it means to think only in another language - but very similar to cummings dilemma, he's wanting to learn to think in metric). So yes, it can be grueling.

At first, I wasn't sure I understood either what it meant by thinking differently. It clicked with me quickly only because I used my photographic memory to visualize the words. I started off by learning 1 new word everyday until I got to learning upwards of 5 to 10 new words daily.

So the best advice I can give, really, is to find what works for you... then RUN with it! LoL.

p.s. If I were to judge how far "5 feet" is... i'd say it's 1.5 meters. That's easy and close enough and still leaves room for the paint :smiley2:

cmburch
03-06-2008, 21:24
I have Oceanic metric gauges. I see sometimes that there is a problem if someone looks at my pressure gauge (Kg/cm2) underwater rather than my fingers on how much air I have left. OMS has both on some of their gauges.

I have European friends from school also my wife is a German National. I’ll have to ask my daughter about her understanding of the metric system since she goes to school mainly in the U.S., but has spent time in Europe with our friends and relatives. I use to ride motorcycles a lot, so I have a good feeling for distances and speed. I also have a good feeling for metric measurements used in cooking. At work, I almost exclusively use metric for mass, pressure, volume, density, velocity, vacuum, – temperature depends on who I am reporting it to and length is about 50/50. So it does help when using it at work and at home. Swimming pools are 25yds x 50m. Out of about 10 tape measures at my house only one is metric. I tend to get confused sometimes when working on my cars that have a mixture especially on threading, so I make notes in the manuals. Also torque settings I pencil in the conversion in the manuals so I can use my Sears torque wrench.

BuzzGA
03-06-2008, 21:53
Most of us here are of a certain age, and probably recall that at one time Congress passed a bill to officially take the US into the metric system of measurement.

It failed miserably--due to the hue and cry of older generations of US citizens who not only disliked the fact that they were no longer using familiar measures, but actively (and in some cases vocally) refused in many instances to utilize it.*

Kids in school were taught metric for about two years, and then the whole thing pretty much fell by the wayside.

I've got to go with cummings66 here, in that if you can learn to think in a system, you can begin to natively utilize that system effectively; the same is true of a foreign language and fluency and comprehension in it.

PPM

*My car gets 40 furlongs to the hogshead, and that's the way I likes it!--Grandpa Simpson

Here in Tucson we still have some leftovers from that law. On I-19, which runs from Tucson to the Mexican border, all the signs are in kilometers. Apparently the idea was to convert some roads with international travelers to metric and see how it went...we know the answer to that

Aussie
03-06-2008, 22:07
It must be hard to only have one system. Offically Australia has had the metric system since the 1960's when we changed from the Imperial system. But some imperial terms are still often used today.

When you ask for someones height we still say 6 foot 3 inches.
We still have 10oz 15oz 20oz beer glasses which have also their metric amount written on the bottom.
We know that when your doing 100mph thats 160kph and you will get a speeding ticket or 100kph is 80mph (100kph is the common speed limit over here)

One metre is roughly 110% longer than a yard (ie 100m = 110yards roughly). So when it comes to water visabilty if you use yards its about the same as metres (roughly over a small distance). I think that will make it alot easier on you when working things out. Over longer distances take off 10% of your yardage.

Maybe change your dive computer to metric mode with most computers allow you to do. Might be worth a try.

Aussie

hoobascooba
03-06-2008, 22:12
I have Oceanic metric gauges. I see sometimes that there is a problem if someone looks at my pressure gauge underwater rather than my fingers on how much air I have left.

hah! for 2000psi, do you hold up a thumb and index finger, and for 3000, a thumb and first 2 fingers???

I still do that all the time!

cummings66
03-06-2008, 22:15
I was originally taught that you don't use fractions in the metric system, ie I couldn't say one and a half meters and would have to say 150 cm for example. Based on what I've read thus far it is correct to say one and a half meters, is this actually how it's done? I would use the unit of measure that fits the situation accuracy requirements, meaning if it was 140 cm's vis by direct measurement I could say about one and a half meters vis but if I wanted accuracy I would say it in terms of the unit that gets me the most accuracy, even so far as mm's of vis if I was anal?

Do you use deca and hecto or is it mostly meters and kilometers that get used? For example, say the vis I've seen is 30 feet, I could say 3 decameters or would 10 meters be better? I guess the question is, what would a native do?

I know the small sizes, mm is something I can easily relate to, cm on the other hand isn't even though I think two and a half of them is our inch, it doesn't visualize, yet. I think what I'm going to do is make a point to start seeing things in metric and hope that it sticks. I'm going to give this an honest shot the only way I know to learn, and that's to start using it without translation.

IMO, I think those of you who use the system natively can help me because it's like learning German in my case. I know very little, but I did discover that what I was taught in school is not how it was used in real life. You have the proper way, and you have the way it's really done. How it's done is what I'm after.

hoobascooba
03-06-2008, 22:17
Maybe change your dive computer to metric mode with most computers allow you to do. Might be worth a try.




might be worth something to have also would be a secondary UW depth gauge that measured in feet. that way, while reading/getting used to your computer, you could try to 'remember' or learn roughly that 18m is about 130 or 140 ft. take your pick.

cummings66
03-06-2008, 22:18
hah! for 2000psi, do you hold up a thumb and index finger, and for 3000, a thumb and first 2 fingers???


That's going to be fun, instead of psi I'll have BAR to deal with, but from what I gather it's easier to sign what you have in a meaningful way. So they claim...

cummings66
03-06-2008, 22:25
Maybe change your dive computer to metric mode with most computers allow you to do. Might be worth a try.


I am going to do so as soon as I can visualize it. I did a dive once with one of our divers who had his dive computer in metric and didn't know it. So when we briefed our plan and I told him my mod was 100 feet, he tried to violate it big time. He was headed for 100 meters, not that he could have got there but he was going to try.

When I switch it will be when I can see with my mind the system, I don't want to make that mistake. I could always do the math and say I won't dive deeper than say 40 meters, but I'd like to understand it in metric without conversion first if you know what I mean.

hoobascooba
03-06-2008, 22:26
I was originally taught that you don't use fractions in the metric system, ie I couldn't say one and a half meters and would have to say 150 cm for example. Based on what I've read thus far it is correct to say one and a half meters, is this actually how it's done? I would use the unit of measure that fits the situation accuracy requirements, meaning if it was 140 cm's vis by direct measurement I could say about one and a half meters vis but if I wanted accuracy I would say it in terms of the unit that gets me the most accuracy, even so far as mm's of vis if I was anal?

I didn't type one and a half meters. Rather, one point five. So that's how a native english speaking German would say it. Otherwise in german, it would actually be said "einundhalb Meter" (one and a half meters).

Do you use deca and hecto or is it mostly meters and kilometers that get used? For example, say the vis I've seen is 30 feet, I could say 3 decameters or would 10 meters be better? I guess the question is, what would a native do?

I always heard meters and kilometers. Just not pronounced the same way :smiley36:

At what point do YOU say "144 inches" as opposed to 12 feet?

I know the small sizes, mm is something I can easily relate to, cm on the other hand isn't even though I think two and a half of them is our inch, it doesn't visualize, yet. I think what I'm going to do is make a point to start seeing things in metric and hope that it sticks. I'm going to give this an honest shot the only way I know to learn, and that's to start using it without translation.

I went to a private one on one German/English counselor that taught German grammar specifically for foreigners. The 'State' usually would help refugees with cost, but I had to pay bookoos of money for my instruction. She absolutely refused to speak english with me. I see now why she did that. Good for her, and good for me!

IMO, I think those of you who use the system natively can help me because it's like learning German in my case. I know very little, but I did discover that what I was taught in school is not how it was used in real life. You have the proper way, and you have the way it's really done. How it's done is what I'm after.

I can't tell you how I did it. I just did. I was immersed. Kinda like scuba diving too, ain't it?:smiley32::smiley20:

hoobascooba
03-06-2008, 22:37
oh wait a minute!

I know now how I did it!!






I was just turning 25 when I moved to Germany... yeah, that's it. 5 years later now I don't think I could do that all over again!

:smilie39::smilie39:

namabiru
03-06-2008, 23:14
Sure you can. When you read packages, look for the metrics and begin referring to them. When you drive, measure out a kilometer and get a feel for it, then start referring to things in kilometers and thinking in kilometers. If you get people who look at you and go "What's that?", say 'I don't know' and refuse to convert for them. Change the setting on your computer so you're looking at metrics. Replace your SPG with metrics--ST sells them, as I recently learned. Start reading temperatures in celsius. You *can* surround yourself with metrics, even in the United States. I did all this stuff to keep myself international when I had to live in the States for a year, and it worked pretty well.

Metrics are ridiculously easy, truth be told. It will be rough at first, but you'll get there.

cmburch
03-06-2008, 23:22
I only use Bar for higher pressures such as presses or chambers. The instruments are normally in Pascal or KPa, but the cylinder gauges are in PSI. So I have to adjust the cylinder pressure for the instrument.

I have the same problem with vacuum since the instruments are metric Torr, but my measuring devices are standard. So I have to calculate by hand and pencil the conversion in the manual and/or put a sign on the part.

Gas flows for instruments are normally in L/min or mL/min – I have to convert these also.

I don’t say one and a half meters – I say one point five meters or convert to cm. So I use decimal system which is a fraction based upon tenths 1/10 instead of 1/2, 1/4, 1/8, 1/16, etc.

I use Centigrade for most temperatures except, I use Kelvin for lower temperatures like liquid helium or liquid nitrogen. For higher temperatures, like an argon plasma it doesn’t really matter C or K. I use Fahrenheit for some air temperatures. Ovens, chillers, incubators, water baths, freezers, refrigerators are normally C. Some furnaces are C while blast furnaces are normally F.

For mass, I mainly use g and mg, sometimes Kg. large masses are normally in tons.

For volume, I mainly use mL and L, sometimes Deca-L, for large volumes I use million gallons MG.

Normal sub-units I use are tenths, hundredths (Percent), thousandths, millionths (mg/L, mg/Kg), billionths (ug/L), and trillionths (ng/L).

navyhmc
03-07-2008, 00:54
I borrowed gear a few times that was metric vs imperial. Dpeth was no biggie, just multiply by the and a "fudge" and you're in the right area of feet. The biggest problem I had at first was the pressure guage was in KPa. When I first looked at it, I was thinking "What the hades is KPa and how do I convert to PSI?"

No problem, put on a full tank and think "it's showing 2100 KPa, Turn at 1400 and have 700 on surface."

It's only as hard as you make it.

PlatypusMan
03-07-2008, 06:43
I was just turning 25 when I moved to Germany... yeah, that's it. 5 years later now I don't think I could do that all over again!

:smilie39::smilie39:


Unsinn. Ich war vor geborenen 51 Jahren in Wiesbaden, und kann innerhalb Grund kommunizieren.

PPM

hoobascooba
03-07-2008, 13:57
I was just turning 25 when I moved to Germany... yeah, that's it. 5 years later now I don't think I could do that all over again!

:smilie39::smilie39:


Unsinn. Ich war vor geborenen 51 Jahren in Wiesbaden, und kann innerhalb Grund kommunizieren.

PPM

na klar. aber wie gut kannst du es sprechen und schreiben? Und wie geht's deine Rechtsschreibung? Grammatik? Aussprache?

What I meant was to just be funny. I was messin with cummins, I was only pointing out that I was younger than I am now. Since I've been back in the states I've already forgotten so much that I learned.

John Yaskowich
03-07-2008, 14:37
[quote=Aussie;142444]

you could try to 'remember' or learn roughly that 18m is about 130 or 140 ft. take your pick.

18m is about 60ft. 40m is ~130ft.

a quick converter is found at >:: World Wide Metric ::< (http://www.worldwidemetric.com/metcal.htm)

coyote
03-07-2008, 16:19
And just top make things a bit more confusing, we don't really use the imperial system in the U.S. We use what is called the "USA system of measurement". The imperial system was adopted by the English in 1824, and the US never bothered to keep things standarized with the folks on the other side of the pond. Little things are different - for example, the USA pint has 16 ounces whereas the Imperial pint has 20 ounces. Also, there are a number of "units' that exist in one system and not another.

And that's today's completely pointless triva fact. :smiley1:

Aussie
03-07-2008, 17:51
[quote=Aussie;142444]

you could try to 'remember' or learn roughly that 18m is about 130 or 140 ft. take your pick.

18m is about 60ft. 40m is ~130ft.

a quick converter is found at >:: World Wide Metric ::< (http://www.worldwidemetric.com/metcal.htm)

Sorry hoobascooba made that quote not this little black duck.

Aussie

cummings66
03-07-2008, 17:56
What I meant was to just be funny. I was messin with cummins, I was only pointing out that I was younger than I am now.

It's true that the younger you are the easier it seems to learn new stuff, plus it's true that if you don't use it you lose it. I know I've forgotten much of the German I did know. I knew enough to get by, but now I know very little of it.

I can get the gist of the written word, but not the total meaning. It depends on how complex it is. I got your post, but had to look up the prior post. I had the 51 years part and could only slight guess the rest, it fades so fast when you can't use it.

I know one guy that is German, he was born there and actually had to man the anti aircraft guns back in WWII. He was in a location that he was shooting at the bombers coming in, and in those planes was my Boss. It's odd, but my boss and him became good friends and through both of them I learned a bit more to history. Turns out that Klaus had no choice, he was 16 I think he said and if he didn't fight his family would have been killed. Klaus and I used to talk a bit in German when I seen him, but since my boss passed away a couple years ago I've not said a single word.

That's why I'm trying to do here, learn it and use it native without having to convert things. If I can use it everyday then it will become a part of me and I will think in it.

For today, lets just say that miles and KM's don't compute for me. Got to put more effort into it. I can't predict a single distance in it, yet.

cummings66
03-07-2008, 18:01
Sorry hoobascooba made that quote not this little black duck.

Even I knew he was off, but I knew what he was trying to say. But that does point out the difficulty of using it from a person here in the states, and he was over there long enough to learn a language. He should have it down better than me, and yet he made a simple error.

That's why I find it hard to do, it's because converting is not the way to go just as translating foreign words to english isn't how you do it. You've got to know it like it's native. Language courses have pictures relating to words, it'd be nice if there was something like that for numbers.

Here's how I do a few of the US measurements. For the foot I picture a ruler, a yard would picture a yardstick. For longer distances I use gun range distances of 25 yards, 50 yards and 100 yards. I know those distances by virtue of having shot guns on those ranges. For miles I know about how far it is and can visually look towards a tree line and tell about how far it is, I sort of base it on distance and how long I feel it will take to get there. For closer distances like 1/4 mile I know how long my gravel road is and use that as a means to measure shorter distances. I know when I walk each stride I take is 2.5 feet because I've measured it over miles, it comes in useful if you hike a lot. That's how I mapped distances, I would count my steps in terms of 5 foot distances, I'd say 1000 of them would be a mile and relocate myself on the topo.

I suppose, I need to convert those visual cues into the metric system so I can see those items that way. It's not as easy for me as some of you think it is. I know in my head how to convert and that's what kills me.

John Yaskowich
03-07-2008, 21:23
And just top make things a bit more confusing, we don't really use the imperial system in the U.S. We use what is called the "USA system of measurement". The imperial system was adopted by the English in 1824, and the US never bothered to keep things standarized with the folks on the other side of the pond. Little things are different - for example, the USA pint has 16 ounces whereas the Imperial pint has 20 ounces. Also, there are a number of "units' that exist in one system and not another.

And that's today's completely pointless triva fact. :smiley1:

And to add even more fun to the mix, some items with the same names have different values. A US liquid ounce is different from a true Imperial ounce. And your gallons are also different.

Check out Units of Measurement (http://www.unc.edu/~rowlett/units/index.html) for more information than your could ever need about units of measure,

Mtrewyn
03-07-2008, 23:52
It is hard to convert from one to the other, I have to think in one or the other, I don't convert from one to the other, pressure is the hardest for me to work with the rest you just have to use and use more, a little at a time you will start to get it.

I think trying to convert back and forth made it harder for me to learn so I stopped ,than it started to gel a little faster.

cummings66
03-08-2008, 07:08
OK, here's what I've come up with.

My HP120 tanks are about 14L tanks at 241 bar. Right now I'm going to round up and say my high breathing rate is currently 23L in doubles, it's about 9L to 28L in singles, depending on the type of dive I do the average I would use is 17L.

My HP100 tanks are about 11.7L at 241 Bar.

Now that I know that some diving things will be easier, but I am curious. Take a common tank size that you have there and tell me how many liters of gas it contains and the Bar it is at. I'm wondering if your tanks are made to the metric system? Not sure how to say that, but is the pressure an even number instead of mine being 241 bar are yours 200 bar for example?

The recreational depth here is 39.6 meters, the O2 MOD is 6 meters. Still working on the Nitrox stuff. For some reason it's not coming out right. I thought I could take the 1.4 PPO2 limit and divide that by the percentage but it is not right. I'll puzzle it out over the course of the day when I have a few idle moments in between work. I'm doing something obvious I suspect. I think that PPO2/ATA gives best mix. Is that right, when you take out the wierd american math it changes enough to make me think and the theory has been taught long enough ago that I may need to dig out my book again. PPO2/Mix gives MOD in ATA. Assuming you remember to sub 1 to get depth in meters as appropriate.

John Yaskowich
03-08-2008, 16:46
(I posted this in another thread which talked about the metric system)

We Canadians have to have the most screwed up implementation of the metric system on earth. For example food is usually advertized in $/pound but the package wiil be marked in $/kilogram (the sign will *usually* also show the $/kg price in much smaller case, or it will show $/100grams (1/10th kilogram) just to make things confusing.) Gas "milage" is shown in litres needed to drive 100 kilometres.

Having the US next door and as our largest trading partner has probably had something to do with it.

Canada has used the metric system since about 1978 and I still don't think totally those units. To me, temperature only means something to me in Fahrenheit. And the biggest gap in the (commonly used) length measurements is between the centimetre and the metre. A centimetre is about the width of a little finger, a metre is about the length of an arm. There is no convienient middle measurement of about a handspan (inch or foot).

And most of the time if you ask a Canadian how far the next gas station is you will probably be told something like "about 10 minutes down the road".

Just the perspective of someone who has lived metric for 30 years but can't shake 20 years of Imperial growing up.

cummings66
03-08-2008, 18:05
And the biggest gap in the (commonly used) length measurements is between the centimetre and the metre. A centimetre is about the width of a little finger, a metre is about the length of an arm. There is no convienient middle measurement of about a handspan (inch or foot).

The decimeter is 1/10 of a meter. Might be closer but still not the same.

doczerothree
03-08-2008, 18:12
But I'm too old to learn metric:smiley11:. It's gotta be a plot.

John Yaskowich
03-09-2008, 11:57
And the biggest gap in the (commonly used) length measurements is between the centimetre and the metre. A centimetre is about the width of a little finger, a metre is about the length of an arm. There is no convienient middle measurement of about a handspan (inch or foot).

The decimeter is 1/10 of a meter. Might be closer but still not the same.
The decimeter is not in common use. The lengths used most often are milimetre, centimetre, metre, kilometre. I have never heard anyone use a decimetre (1/10th a metre) or a decametre (10 metres).