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Why Does the US Cling To Imperial Measurements? 2288

PhunkySchtuff writes "As one of only three countries on Earth that hasn't converted to a metric system of units and measurements, there is a huge amount of resistance within the US to change the status quo. Whilst the cost of switching would be huge, there is also a massive hidden cost in not switching when dealing with the rest of the world (except for Liberia & Burma, the only other two countries that don't use the metric system) With one of the largest organisations in the US, the military, using metric units extensively, why does the general public in the US still cling to their customary system of units?"
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Why Does the US Cling To Imperial Measurements?

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  • by suso ( 153703 ) * on Wednesday April 20, 2011 @10:32PM (#35887618) Homepage Journal

    I think its alright to have a few different systems in the world. Sure, there is an attractiveness to consolidation. But what are we going to do when we encounter aliens? Demand that they switch to the metric system? I'm actually serious. I'm not saying it will happen tomorrow or even in the next decade or century, but eventually it will. There is a lot to be said for having a tolerance for the differences among cultures and retaining those differences.

    • Re: (Score:3, Funny)

      by log0n ( 18224 )

      I disagree.

      • by mywhitewolf ( 1923488 ) on Wednesday April 20, 2011 @10:46PM (#35887814)
        Its much more intuitive for an advanced civilization to have a base(x) counting system with measurement standards being built of the counting system. so aliens are more likely to understand a metric system better than imperial. Aliens should be able to understand the true nature of mathematics and use that to classify sizes, not the average size of a foot.

        However i disagree with America conforming "just because". we haven't even moved to a base 10 timing metric yet, who are we to judge?
    • by Anonymous Coward on Wednesday April 20, 2011 @10:34PM (#35887648)

      Well since you can ask ridiculous hypothetical questions: what happens if the aliens use metric?

    • by thisnamestoolong ( 1584383 ) on Wednesday April 20, 2011 @10:56PM (#35887948)
      You are missing the point. The main argument for the metric system is NOT because it is standard, regardless of what TFA says. The reason we should switch to the metric system is the same that the rest of the world has already -- it simply makes a whole lot more sense. Everything is base 10, and if you know what the basic unit of measurement is you can very easily figure out how to go between units simply by moving a decimal place. Imperial measures, on the other hand, are totally psychotic. 12 inches to a foot, 3 feet to a yard, 5,280 feet to a mile. It is the type of nonsense that we would expect to see in Dr. Seuss story, not it real life.
    • by formfeed ( 703859 ) on Wednesday April 20, 2011 @11:31PM (#35888502)
      It is really bad.

      But I admit it doesn't matter whether you call it centimeter or inch or measure the distance by the eyebrow length of the great communicator Ronald Reagan.
      Call it the freedom fighting anti-communist inch of the greatest empire on earth, if you wish. And make it twice as long as every other country's unit.
      Doesn't really matter.

      What matters, is the fucked up unit system within the imperial system.
      Let's say you want to convert 1/8 inch rainfall to gallons per square yard? Yes, doable, sure. In the metric system however it's just counting zeros and shifting a decimal point.
      A meter has 100 centimeter, so a square meter has a 100x100 square centimeter, or 10000. Easy, just count zeros. Liters in a cubic meter? Easy. Kilograms per square centimeter to tons per square meter? Easy, just counting zeros.
      But square inch to square feet? Square miles? floz to gallon?
      And if that isn't bad enough, add all the competing units used in the US. Air pressure is a different unit when the air is in the atmosphere or in the tire. For energy, there are different units depending on whether it is an air conditioner, a furnace, a car, what company I get the energy from, and whether the second Friday after Lincoln's birthday falls on a full moon.

      The difference to the metric system is not, that inch and cm are different. The beauty of the metric system is that you have a consistent system. And that's why scientific calculations are usually done in metric and the result is then transfered back to imperial, so the US public won't get worried that the French took over, communists gained control of the class room, or that their politicians betrayed the greatest conceivable nation on earth.

      • by VendingMenace ( 613279 ) on Thursday April 21, 2011 @07:57AM (#35891800)

        The imperial system units only appear fucked up to our modern perspective.

        Right now, measuring things is a relatively simple procedure. We have tools to divide thing up as we wish. Want to saw a 1 meter board into 1/3rd of a meter? No sweat, just divide it by 3 and measure out 33.333... cm to whatever precision you wish. Doesn't mater that this is a rather difficult number to deal with in the real world. We have gates we can dial in the distance we want with digital readouts and whatnot.

        But now consider being a dude trying to build a house in 16th century. You would like to make sure that your corners are square and you happen to know that a 3-4-5 triangle will give you a right angle. Cool. Not too hard to divide a rope into three equal sections or four equal sections either. Just fold it into thirds for the "3" unit and in half twice for the "4" unit. However, what this means is that your desire for square corners dictates that the natural units that you are working in are 3 and 4. Thus, it makes sense that the "total" unit should be divisible by 3 AND 4. So...12. This is why the foot is twelve inches -- some dude a long time ago wanted to build a house with square corners.

        The metric system would have been totally unnatural for a person in the 16th century -- as it is only divisible by 2 and 5. In our world where machines handle both the math and the measurement, this is OK. If you don't have these fancy instruments, it is not.

  • Because.... (Score:3, Insightful)

    by H0D_G ( 894033 ) on Wednesday April 20, 2011 @10:34PM (#35887642)

    It'd smack too much of you giving in to the French.

    Seriously, it's really frustrating when watching American science documentaries and all of the units aren't SI units. Scientists should always, always use metric.

    • Re:Because.... (Score:4, Insightful)

      by Anonymous Coward on Wednesday April 20, 2011 @10:40PM (#35887718)

      Real science is done non-dimensionally

    • Re:Because.... (Score:5, Insightful)

      by wvmarle ( 1070040 ) on Wednesday April 20, 2011 @10:42PM (#35887736)

      What is even worse, is scientific shows like Mythbusters use BOTH systems. Usually they use metric, usually it's F but sometimes it's C. Weighs usually pounds, but they also have used (kilo)grammes. Distance is usually inches and feet, but when bouncing a baseball they were measuring the bounce in cm - while other parts of the same experiment were using inches and feet.

      There is no consistency, and that alone can give rise to errors. It doesn't really matter whether one uses cm or inches, or C or F as long as it's consistent. Forget to write down the unit once, and it's guesswork that's left. Have a thermometer with both scales - oops which scale were we using again this time?

      • What is even worse, is scientific shows like Mythbusters use BOTH systems.
        There is no consistency, and that alone can give rise to errors

        It's a pre-recorded show. How can there be any errors?

        They're just trying to introduce the metric system to viewers. If they were to use completely Imperial units, viewers wouldn't be learning anything about the metric system. If they were to use completely metric units, U.S. viewers would be discouraged and stop watching. By mixing the units up, they're keepi

    • Re:Because.... (Score:5, Informative)

      by Anonymous Coward on Wednesday April 20, 2011 @10:47PM (#35887836)

      Hi, American scientist here. We do use metric.

      When things are done for the media (documentaries, etc), they are translated into Imperial units, because the majority of the (American) audience would have no idea how big or small of things we were talking about when talking in some strange units they aren't familiar with.

      • It's frustrating for us though when you air your documentaries in Canada, and are quoting ounces, Fahrenheit, yards, etc, since I honestly have no clue what you are talking about. I think it would be a nice gesture for us if you could at least subtitle the imperial measurements in metric or use both, if you must.

  • by cob666 ( 656740 ) on Wednesday April 20, 2011 @10:35PM (#35887660) Homepage
    I found this online somewhere:

    In 1988, Congress passed the Omnibus Trade and Competitiveness Act, which designates "the metric system of measurement as the preferred system of weights and measures for United States trade and commerce." Among many other things, the act requires federal agencies to use metric measurements in nearly all of their activities, although there are still exceptions allowing traditional units to be used in documents intended for consumers. The real purpose of the act was to improve the competitiveness of American industry in international markets by encouraging industries to design, produce, and sell products in metric units.

  • by matty619 ( 630957 ) on Wednesday April 20, 2011 @10:38PM (#35887694)

    Americans like monosyllabic or abbreviated words wherever possible. Especially in commonly used words, like those involving measurements. We've got pound, inch, foot, yard, pint, quart, and gallon....gallon being one of the few multisyllabic words. Most metric metrics (lol...ya, I just did that) are multi syllable compound words, and most of them don't have any obvious way of being shortened. Americans just don't want to say "Kilometer" when they can say "mile. They don't want to say "centimeter" when they can say "inch".

    The Metric System is elegantly simple and beautiful, in everything but the English pronunciation of said metrics. What a shame.

    • To be fair, in casual speech, people in metric countries say "k" for kilometres. As in "it's about 5 kay down the road". Similarly for millimetres they tend to say 'mil' (this could also be millilitre, depending on context).

      No short-form of cm as far as I'm aware though.

      • Very true. But it's still one of the reasons the public at large has resisted every attempt to convert. Imperial measurements are just more comfortable in everyday speech. This is just my personal theory of course, but I believe it holds water. Perhaps a gallon or so ;)

    • by Randle_Revar ( 229304 ) <> on Wednesday April 20, 2011 @11:51PM (#35888776) Homepage Journal

      A couple of redneck friends of mine started using "klick" as a distance because they found out the US military uses it. Imagine their reaction when they found out (from me) that it was metric (almost as bad as being French, as far as they are concerned).

  • by JeffSh ( 71237 ) <> on Wednesday April 20, 2011 @10:40PM (#35887714)

    The interesting thing about this is that Liberia is comprised of US ex-pats; slaves who populated the country when "Back to Africa" was embraced by ex-slaves. It's really amazing to study this area of history. Even their flag is Red White and Blue. It's weird that they share the same addiction to imperial measurement also.

  • by Stenchwarrior ( 1335051 ) on Wednesday April 20, 2011 @10:42PM (#35887734)

    I've often wondered this very same thing. I grew up having learned both systems but it wasn't until I joined the Army that I realized how much easier the metric system is to actually use, not just on paper. Fractions are quite possibly the dumbest incarnation of math we humans could have ever invented; I could understand if it actually made things easier, but it does not.

    Perhaps there are jobs created or money to be made with continuing to use Imperial and metric at the same time e.g., tools created in both systems.

    On the other hand, how can we Americans continue our ethnocentric ways if we were to join the rest of the world? (ok that was a troll, but come holds some truth).

    • Re:Good Question (Score:5, Informative)

      by Solandri ( 704621 ) on Wednesday April 20, 2011 @11:06PM (#35888126)

      Fractions are quite possibly the dumbest incarnation of math we humans could have ever invented; I could understand if it actually made things easier, but it does not.

      Fractional units come from back in the days when you couldn't buy a calibrated ruler at the corner store. If you don't have a ruler, the best you can do is take an object of known measure (say 1 yard of cloth) and divide it into equal parts (fold it into thirds to get three 1-foot segments). This is probably easiest to see with measures of volume. The English system goes by powers of 2. 1 gallon is 4 quarts (missing unit in between). 1 quart is 2 pints. 1 pint is 2 cups. 1 cup is 2 gills. Why powers of 2? If you don't have calibrated beakers, how do you divide a volume of liquid into even parts? You split it in half (by weight) over and over. So it makes sense for your units of measurement to coincide with dividing in half over and over.

      So back in the day when measuring was the hard part, fractions made sense. Today, measuring is the easy part, and calculating with the measurements afterward is the (relatively) hard part. So metric units (powers of 10) make more sense.

  • by devphaeton ( 695736 ) on Wednesday April 20, 2011 @10:43PM (#35887754)

    Dunno about you guys, but whenever I have to actually design or build something, I use the metric system. I have foreign cookbooks where everything is metric, and my scales and measuring equipment all accommodate. Sure, sometimes i have to use imperial, such as when working on older cars, fixing someone else's handiwork, etc., but I also know a lot of common conversions off the top of my head. I've actually been called a "communist" once because of this. I consider it an accomplishment.

    Besides, all the engineering, manufacturing, scientific and medical sectors in the U.S. have been using the metric system for decades. /dev/phaeton

  • Change the name! (Score:5, Informative)

    by Thagg ( 9904 ) <> on Wednesday April 20, 2011 @10:43PM (#35887772) Journal

    Call them American units!

    I mean, we don't use Imperial gallons here anyway

  • by ugen ( 93902 ) on Wednesday April 20, 2011 @10:55PM (#35887942)

    I was born and raised in a country that is firmly and decidedly "metric". I finished school and college knowing nothing but metric system. So, you could say that metric would be my "natural choice".

    Then I moved to US. At first non-metric units were a PIA. Admittedly, conversions are not nearly as convenient - you can't just shuffle a decimal dot around.

    After a while, though - it really started to "grow on me". The first shift occurred when I started driving a lot - both in US and in Europe. For reasons, that are purely subjective, I began to feel like a mile (statutory or nautical, your pick) is a more "natural" unit of distance. Kilometer always fell short. In a way mile represented what I feel a "decent distance" should feel like.

    Then, as I took up a hobby (or a waste of money, depending on your take on it) that required significant amounts of engineering, machining and manual work - I started to feel the same way about other units. Inch is exactly what a "small but human scale" distance should be (it is unusually pretty close to what you'd get if you were to show a "very short distance" by making a semi-circle with your thumb and index fingers, like a slightly opened O), so did the foot, the ounce for "a small amount of weight" etc. I also began to appreciate division of inches into powers of two (rather than centimeters into powers of ten etc).

    In time, conversions became a non-issue. In fact, it probably helps keep my "doing arithmetic in my head" skills less rusty.

      I still occasionally use metrics as a way to do "thru conversions", in particular between volume and mass (because one deci-meter of water is one liter of water is approx 1 kg). I also use metrics where they are the only units - such as electricity, for example.

    But at this point, I would not voluntarily go back to metric system for anything that's related to weights and dimensions.

    YMMV. That said, perhaps there are other people who feel like me. If so - that's your answer as to why Imperial units are still here (and, hopefully, going to stay for a while)

    • Re: (Score:3, Insightful)

      by Anonymous Coward

      That's complete and utter hogwash. You think imperial is "natural" simply because you are more used to it. Any non-American (except for a few Brits, Aussies and Kanuks) think metric units are more "natural".

      Now, there is no question that computing with metric units is way more natural. Here is an example: you need to put 12 equally-spaced fence posts along a particular length, say 13 feet 5 inches and 3/8. How far apart should the fence post be? You need to divide 12'5''3/8 by 11. Go ahead, I'm waiting.....

  • by meerling ( 1487879 ) on Wednesday April 20, 2011 @10:56PM (#35887956)
    I was taught metrics in 1st grade, that was back in the 70s, and it's so easy a 7 year old can master it.
    This imperial crap almost everyone else in the US uses is rather incomprehensible.
    Your foot is divided by 12 inches, which are divided by 16ths, yet it's 3 foot to the yard, and god only knows how many yards in a mile. Here's a fun trick to do, ask some of your friends or relatives how many yards are in a mile. How many of them will actually give you an answer, much less the right one. Bet more than half can't, at least without someone else how many feet are in the mile. And let's not forget the long delay as they try to divide by 3. Not very impressive is it.
    Now, ask some kid who knows metric how many meters are in a kilometer. How many centimeters are in a kilometer. Bet you that prepubescent child that know metric will give you an answer really fast, and be right every time. It's because metric is a concise system based on 10 that even an imbecile can understand it, and smart people make far fewer mistakes because it's a consistent system.

    You want to screw over the country when dealing with the rest of the world, keep using imperial.
    We've lost people and multi-million dollar machines because of imperial, is it really worth it?
  • Building Industry (Score:5, Informative)

    by digitect ( 217483 ) <digitect.dancingpaper@com> on Wednesday April 20, 2011 @11:13PM (#35888224)

    I'm an architect, and I'll tell you that the building industry is so entrenched in imperial measurements I haven't used my metric scale in five years. Every single product is based on imperial dimensions, meaning design, coordination, and calculation require the same.

    Some examples: joist spacing tables display span lengths for 16" and 24" on center spacings. These tables are everywhere and they've been around unchanged forever. All the plywood sub-flooring is in 48" x 96" sheets. Works great for either joist spacing and in either horizontal or vertical orientation. If you buy a house in the US, standard is an 8' ceiling, "up scale" is 9', exclusive is 10'. (Who would know the status of a 2600mm ceiling?!) Studs are already available and pre-cut to accomplish these heights. Drywall is sold in these lengths. Concrete and soil are measured in cubic yards, roofing by square, carpeting by yard, ceiling tiles in 24" squares, etc. The International Building Code (what most of us use) gives dimensions in Imperial dimensions, including sprinkler head spacing, floor loading requirements, floor-to-floor, allowable areas, etc. Think about it, every plumbing, gas, and sanitary drain system connecting your building to infrastructure is calculated in imperial from engineering tables more than fifty years old. Tape measures are all imperial as is surveying equipment. The entire commercial real estate market is in imperial, changing to metric would crush every agent and developer trying to calculate pro-forma for all real estate in the country. Lumber mills and woodworking equipment that has been around for years and that produce moldings, doors, boards, handrails, furniture, etc., are all imperial. Existing surveys, architectural drawings, engineering calculations, and every other kind of specification, calibration, documentation, regulation, etc. in the building industry is imperial, doing a simple renovation or addition (actually >50% of the building industry) would require the overhead of converting all existing information prior to proceeding.

    I've worked on several metric buildings. It takes about two days to get into the swing of it. From an architect's view, scaling and plotting drawings is much simpler than imperial. Not having to deal with foot-inches is easier, too. (Although everybody seems to disagree about whether to use m, cm, or mm. We have native metric users that can't even agree on that.) But it doesn't take long before somebody starts discussing "hard" vs. "soft" metric and wondering if buying 900 mm doors will cost 50% more than 36" doors, if a wheelchair can still fit through it, and where they might come from in the local market if they can even be found. About a day later the whole endeavor goes down the tube when one party in the process gets nervous. We usually switch to "soft" metric for a few weeks (designing in imperial but also stating metric on the drawings) and then abandon the entire metric effort in favor of imperial. The only way a project will stay in true hard metric is if it is being built overseas.

    We're going to have to go metric one system at a time. First was soda bottles. Then automobiles. Science is there, and a lot of SI units are becoming comfortable on food packaging. The building industry is going to have to do the same, I predict in places where highly manufactured components interface with imperial ones in a relatively unimportant way. (Think windows cut into a wall.) Commercially, roof membranes are specified in mm and many other components are manufactured in hard metric dimensions with proximal imperial values (like thicknesses of drywall and plywood). But things like bricks, lumber, and plumbing pipe may take a while.

    • Re:Building Industry (Score:5, Interesting)

      by tm2b ( 42473 ) on Thursday April 21, 2011 @04:46AM (#35890826) Journal
      Bucky Fuller wrote about this, in the context of how quickly humans adopt new technologies. The sequence you describe is exactly what he believed: in essence, the more frivolous a technology is to our live and safety, and the shorter the product cycle, the faster humans can adopt that technology. Thus, food - fast product cycle, beverages - fast cycle and purely luxury, we can change quickly over a matter of years. Automobiles have a medium life cycle and are of varying criticality to our lives (compare rural Texas with Manhattan or urban Chicqgo), so they will be a medium length of time tomadopt - decades, plus or minus. But housing? That's a very long product cycle and we have a very strong emotional connection to our shelter, so we are very conservative about how we build them. It'll take a century (let's say, from 1960-1980ish) to change.

      It was a very interesting discussion in his book, _Critical Path_, where he concluded that for certain kinds of inventions, the inventor wishing to help humanity should publish his housing inventions (the geodesic dome and the dymaxion house, in this case), perhaps work to promote them for some special purposes to get them into intellectual circulation (he worked to get them used by scientific and military organizations), and then move on to other topics - because without a specific adaptive pressure (eg, (my example) PEX to replace now-expensive copper plumbing) housing inventions would take more than a lifetime to go into general use.

      Bucky Fuller was a dozen kinds of awesome.
  • by obarthelemy ( 160321 ) on Wednesday April 20, 2011 @11:21PM (#35888340)

    The real reason is that, subconsciously, US citizens woe the day they left the British empire. They have a deep, age-old yearning to go back into the fold, and thus cherish this last remnant of britishness.

    Last I heard, they are also starting to have those quaint tea parties, too. I'm holding out for the day they trade pancackes for scones!.

  • by Lord Kano ( 13027 ) on Wednesday April 20, 2011 @11:30PM (#35888482) Homepage Journal

    In the US, the spirit of rugged individualism is held up an an ideal to aspire to. In the US, the government imposing mandates saying "You WILL use THIS system." is likely to result in a backlash. More so than in many other places.

    Look at the recent health care legislation. There are arguments pro and counter, but Americans hear that they won't have a choice and they freak the fuck out. So much so that they gave one house of Congress to the opposition party just to slow that kind of thing down.

    Personally, I still don't *think* in metric. I am 6'1". I would have to do math to figure out exactly how many meters that is.

    I have to mentally convert km to miles to get a mental picture of distances.

    I don't expect the US to convert in my or my childrens' lifetimes.


  • by Michael Woodhams ( 112247 ) on Thursday April 21, 2011 @02:52AM (#35890154) Journal

    This post is an example of autoplagurism [].

    A good system of units needs:
    1) Base units which are well defined and independently reconstructible (i.e. a suitably equipped lab can calibrate their equipment purely from the definition of the units.)
    2) Logically constructed compound units (e.g. units of force are derived from the units of mass, time and distance.)
    3) Logically constructed convenience units (e.g. kilometres for use for distances which would be an inconveniently large number of metres.)
    4) To be widely used.

    The initial choice of your base units is largely arbitrary - whether it was a from a not-very-accurate measure of a king's foot size or from a not-very-accurate measure of the Earth's circumference. Item (1) can be satisfied equally well (or, in the case of mass, badly) by the metric or imperial systems. The definition of the metre has long since changed from the size of the Earth to quantities measurable in a lab (as has the definition of the foot.)

    The SI system (based on metric measures) beats the imperial system hands down on items 2 and 3, and because of this now has a large advantage also on item 4.

    Item 2: In Imperial you might measure (heat) energy in BTU and mechanical energy in some mixture of foot-pounds-seconds, but then you need a conversion factor to compare the two. Such conversion factors are never needed in SI.

    Item 3: Imperial also messes up the convenience units by having lots of weird conversion factors (e.g. an acre is (I think) a furlong by a chain. How many square feet is that? How many ounces in a ton?*) Metric uses convenience units constructed from base units via consistently named factors of 10 or 1000.

    One could go a step further, and define your fundamental units in terms of fundamental physical constants (i.e. the Plank mass, Plank time and Plank distance, charge on an electron, etc.) In such a system of units, the speed of light is 1, the formula for the energy of a photon doesn't need a constant in it etc. In practice, we can't use such a system, because we can't measure (in particular) the universal gravitational constant G with sufficient accuracy. Every time we got a better measure of G, our entire system of units would need to be updated. (I.e. with current technology, this system can't satisfy requirement (1) above.)

    * And how many different sorts of ounces and tons are there? It is quite a few.