Whilst standardisation is obviously important, the article references an anecdote where a building had to lose a storey due to the usage of the ‘wrong type of foot’. This does not seem overly plausible given the error would be <2mm over the height of the Burj Khalifa.

It was likely the measurement of the distance between the airport and the building that was the problem.

edit: thinking about it, it still doesn't make sense. The difference in distance would be about 2 cm over 10 km.

"international foot"

Almost every other nation uses the meter.

India uses foot (that's 15% of the world by population)

Everywhere I read (including https://en.wikipedia.org/wiki/Metrication_in_India) says that India is using the metric system since somewhere around ~1960.

Is US's consistent refusal to adopt something more common like the metric system the ultimate display of "Not invented here" syndrome? (I know imperial was invented by the British, but it's largely just the US left using it) Feels like everyone would be better off if the switch just happened already, as it'll happen one day or another. But they keep on fighting it off, for some reason.

Or does the imperial system have some advantage over metric (not including the fact that everything in the US is already using imperial) that makes it infeasible to change?

In 1793, Thomas Jefferson requested artifacts from France that could be used to adopt the metric system in the United States, and Joseph Dombey was sent from France with a standard kilogram. Before reaching the United States, Dombey's ship was blown off course by a storm and captured by pirates, and he died in captivity on Montserrat.

More seriously, blame the Reagan administration.

https://en.wikipedia.org/wiki/Metrication_in_the_United_Stat...

Thanks for that link! Seems to outline that there has been many attempts, some still ongoing, but not making a lot of progress.

Seems weird to fault all of these failed attempts to the Reagan administration, but I guess that's also an American thing to do, attribute issues to one group of people, not the one you're in, but "the other group".

but not making a lot of progress

That part reminded me of Puerto Rico. Streets are marked with kilometer markers, rural addresses are street and km and hectometers. Also everyone miles for everything else.

I’m actually not sure which conversion failed.

And land is measured in "spanish acres" as well (Cuerda).

And two different scales of magnitudes (US-style "short scale", and "long scale" from Spanish colonial days), meaning two different meanings for millions and billions!

https://metricpioneer.wordpress.com/2014/01/05/long-scale-an...

I know imperial was invented by the British, but it's largely just the US left using it

According to wikipedia, the US do not use the "Imperial System" but the "United States customary units" and they are not exactly equivalent, although they both derive from the "English units ".¹

Also, from the article: "The international foot is exactly 0.3048 of a meter". And it seems the international yard and pound are defined using the SI units as the reference.² (Edit: So by transitivity they also are defined using caesium-133 atom's radiation, light speed in vacuum and Planck constant.)

¹ https://en.wikipedia.org/wiki/Comparison_of_the_imperial_and...

² https://en.wikipedia.org/wiki/International_yard_and_pound

Customary Units and Imperial measurements are bad, we all know that. However, play Devils Advocate for a moment to see the benefits of these allegedly backwards measurements. Take the foot. This is twelve inches. You can divide a foot into thirds or sixths without any recurring numbers. This is of practical application.

If you are working with some DIY task and everything is in Imperial measurements then it all works out as easy as Lego pieces.

Yeah, duodecimal systems (base 12) rock! But is the customary units system consistently duodecimal? Iirc it's not, but I might misremember.

No. E.g. a foot is 12 inches, but a yard is 3 feet.

Thanks, this was what I was looking for. I can totally understand it's easier to cut up a plank if it's twelve inches, in thirds, using customary/imperial, as you get even numbers, compared to with metric, where you'd end up with 0.33... meters for a one meter plan. However, for a 1.2 meter plank, you'd end up with 0.4 pieces. So while I understand how it's beneficial, I don't quite understand how it's beneficial.

It's beneficial in that it lets you score points in theoretical arguments on the internet.

In practice it doesn't matter. For example, the floor of my bathroom is ten feet wide. I recently had to replace it, which in practice meant I had to cut a plank 9 feet 11.5 inches on one side and 10 feet 0.25 inches on the other side. It seems that the original carpenter, when dividing his plank by 3, eyeballed it it more or less so it looked right and just sort of waved their saw in the general direction of correct. It turns out that in reality, the actual arbitrary units are irrelevant.

But you know, bikeshedding on which arbitrary system of units is best is a pretty effective way to procrastinate finishing off that bathroom renovation.

Yeah, this kind of thing annoys me to no end when I scroll through these kind of debates in comment threads. I wonder if people who pose these hypotheticals about dividing lengths down would be surprised that tradesmen and carpenters in the rest of the world get on just fine, and don’t need a maths degree to work this kind of thing out!

A lot of the arguments though (and some of the most impassioned) mostly boil down to “I’m more familiar with this system so I assume it’s better” - for example, any time that people say that customary units are “more human scales” or “fractions are easier to understand than decimals” whatever. It actually makes basically no difference in practice, it’s just that growing up with one system or the other makes you a lot more familiar with it!

Yeah, just look at how easily these mechanics calculate a distance: https://m.youtube.com/watch?v=pikrntjcbyw

Yes, twelve is a wonderful number. You can get a half, a third, a fourth, a sixth. Those are very useful.

Ten only lets you get a half or a fifth. It's a much sparser set of subdivisions.

The same is true if you compare a yard with a meter. There's nothing wrong with either measure, but a yard gives you a lot more factors to work with.

True, but nothing prevents you from using dimensions which are a multiple of 12 in the metric system.

For instance, over here the standard size for a sheet of plywood is 1200 x 2400 mm.

Take the foot. This is twelve inches.

I think the foot is the only unit that is useful, otherwise converting between inches/feet/yards/miles get a bit ridiculous.

Also doing mathematical operations gets weird if you have to add/subtract 4' 3/4" and 2' 1/8".

Surveyors, the subject of this article, actually use decimalized feet on their rods (IIRC) given the errors that inches and such can add. So while inches-feet may be useful in the wood shop, in other places it's a problem.

I have tools which are almost all customary units.

Sockets, Allen wrenches, calipers, wrenches, drill bits, taps/dies. All customary. Its just what's available used here.

Can't you convert the measurement from customary to metric, or from metric to customary? Why does it matter what system the tool was designed for?

Obviously anything that can be measured in customary can also be measured in metric.

The US uses different bolt threads than the rest of the world. Just today I had to buy an 1/4 inch long 8-32 threaded screw to fix our stroller. The 8 refers to a standard diameter in the US system, and the 32 means "32 threads per inch".

How does this work now that almost all products are global and most are manufactured outside the US? Does a Ford engine get designed in both customary for in the US and in metric for the rest of the world?

At this point, new cars are 100% metric, with the exception of tire sizes, which are still inches (usually integer inches, sometimes half inches too), and have been for a pretty long time (switching seems to have started in the late 80s / early 90s where cars would have both types of fasteners, and by the end of the 90s, it was just metric). This probably has something to do with the increasingly global supply chains, and increasingly global parts suppliers.

Oh, and the speedometer and the odometer. The digital ones are probably counting meters and converting though.

It’s funny that the super-American icon of the car has switched but that this hasn’t caused everyone else to switch. My image of America is a parent and child working on their car together in their garage. Would have thought that would have gotten everyone into metric over the last few decades.

If you start from scratch, sure.

But if you're e.g. repairing existing equipment, then the customary and SI units are incompatible. Say, a 1/4 inch bolt head is too large for a 6 mm wrench, but too small for a 8 mm (which is typically the next step up from 6mm).

For this reason I had to buy some wrenches in customary units to fix a lawnmower engine.

But if you're e.g. repairing existing equipment, then the customary and SI units are incompatible. Say, a 1/4 inch bolt head is too large for a 6 mm wrench, but too small for a 8 mm (which is typically the next step up from 6mm).

Where is the problem? Buy a 6.35mm wrench for your 6.35mm bolt head.

In any larger workshop over here there is one toolchest usually marked in some bright and ugly color, all the tools marked in the same color, containing "Zollwerkzeug". That is, tools in inch sizes. You rarely need them, but on occasion you come across something from the other side of the pond where your 8mm wrench would just damage the head of your bolt. But often you can also get the job done with a monkey wrench.

However, this means that really changing over to metric, meaning also using international standards for tools, screws, bolts, wires, etc., needs buying new tools and material. I'm not sure how many metric tools there are in a typical US workshop, but I can imagine that they are not too common at the moment.

The majority of US consumer grade ratchet/wrench sets have both US and metric sizes. There are enough metric nuts and bolts in random things that you really do need both.

It’s even more confusing than that. They use the British system prior to imperial standardisation, so one has both US customary and imperial units of inch etc measurements. Which is why volumes and amount of sub units are different between the two.

It gets particularly confusing when people start comparing mpg for US and British cars, as the two gallons are not the same, I've seen so many arguments online where people are flat out comparing differenteasures and assuming they were the same.

It gets particularly confusing when people start comparing mpg for US and British cars, as the two gallons are not the same

TBF mpg is a terrible unit to compare car efficiency regardless of which gallon you use. It's only more convenient to evaluate the range you have on a tank.

I'm obviously missing something. Why would distance travelled on a unit of fuel be a bad way to measure the efficiency of a car?

I know that such measures are always imprecise due to different driving styles/conditions etc. So what is a better way to measure the efficiency of a car?

I'm obviously missing something. Why would distance travelled on a unit of fuel be a bad way to measure the efficiency of a car?

Because it has a sublinear relationship to absolute efficiency: an 11mpg car is significantly more efficient than a 10mpg car, while a 41mpg car much less so in relation to a 40mpg car: both provide an extra mile per gallon, which translates into a 10% and 2.5% increase in efficiency respectively.

So what is a better way to measure the efficiency of a car?

gpm (aka L/100km which is what's used in most metric countries).

It's less convenient when you know how much fuel you have and want to know what distance you can expect, but it's way more convenient to compare efficiencies, as well as to calculate how much fuel you'll need for a given trip: the examples above are 21.4L/100, 23.5L/100, 5.7 L/100km and 5.9 L/100km. From this, it's obvious that the absolute gain in efficiency is much greater going from 10 to 11 (2L/100km economy) than from 40 to 41 (0.2L/100km)

Well, even if the better unit is liters per 100km, you’d still face the same problems because the UK/US would be talking about gallons per x miles where they would still face the issue the poster described of differing units of gallons.

I tried to explain this, but it turns out to be kind of hard, so instead I found a reference for you: https://www.bunniestudios.com/blog/?p=257

Basically, it makes it easier to compare fuel economy differences at different points in the scale because they become subtraction problems instead of division problems. This is because usually the amount you are going to drive is fixed, and MPG puts the miles in the numerator, while "gpm" puts the fixed miles in the denominator, I think.

Only if you don't drive for fun. If you do, it's a lot more useful to know how far you can get on a tank.

The best way I've heard it phrased is that europeans 2ant to know much much fuel they need to get to their destination, while americans want to know how far they can go on a tank. Its obviously oversimplified/not relevant/other pedantic nitpicking but it captures the different relationship americans in general have with driving and their cars

They use the British system prior to imperial standardisation, so one has both US customary and imperial units of inch etc measurements.

In modern parlance most of these should be identical under the 1959 international yard and pound whose entire point was to unify measurements which previously diverged slightly (as well as define them in metric/SI terms). US "Survey" units are really the pre-intenational versions.

The units which were not unified are mostly those of volume, so imperial volumes and US customary volumes differ quite a bit (plus the US has "fluid" and "dry" units): imperial units are the largest, then come US dry units (97% of imperial) followed by US fluid units units (83% of imperial).

having a unit of weight and a unit of volume share the same name is unspeakably stupid. why? WHY?

Apparently it's because a fluid ounce of water is about an (avoirdupois) ounce so, you know, super helpful reminder!

Like the pound being a unit of currency, a unit of mass, a unit of force, a unit of energy and a unit of torque (especially the latter two, who doesn't love having foot-pound and foot-pound being completely different things?)

a machinist told me that when he had to start doing metric stuff it was all the same dimensions, but converted to metric. so instead of 1/64" he had to mill 0.396875mm. even if everything new designed was in metric with fairly round numbers, you still have a ton of existing stuff designed with imperial units that needs to be taken into account and designed around. the result in some cases is that you get none of the benefits from metric or imperial. and your machinist needs to buy new equipment.

the main thing metric has going for it is that it's the same radix as our counting system and is consistant (as opposed to base12 and then base5280).

There are a few more advantages, especially when machining. There is a large system of standardized metric parts, e.g. washers, screws, etc. available on the cheap because they are needed everywhere. Whereas the US mess of screw sizes, denominations and threads produces a nonending headache of unavailability, high price and non-fitting but similar-looking parts.

Yes, the changeover will be ugly and involve redoing all your plans at some point. But after that you will see how much you are missing out...

there's a bicycle suspension company that's all-metric except for a single screw to adjust tension. apparently the metric screws had too steep of threads and didnt allow for the level of fine adjustment they wanted.

clearly we should create another standard to encompass all these cases and alleviate confusion.

It's political, just like wearing masks to prevent covid infection has become politicized. Both masks and meters have become associated with left-wing intellectual elites, and so the right reflexively rebels against them.

EDIT: to all the people downvoting this comment without explaining why: you are actually proving my point.

You forgot the step where left-wing intellectual elites ridiculed people for wearing masks as it "doesn't protect anyway and creates a false sense of security". If anything, I would imagine masks to be a prepper thing, so I would have thought more popular on the right, but I guess there is no logic anymore.

Masks don't protect the person who wears them, they protect the people around the people who wear them, so they only work if everyone wears them. In the early days of the pandemic there weren't enough masks for the general public (because the Trump administration had sent a significant portion of the U.S. supply to China [1]) so there was a desire to reserve the limited remaining supply for health care workers.

Comments like yours which obfuscate basic facts like this are a perfect example of the kind of politicization I'm talking about.

[1] https://www.snopes.com/fact-check/us-tons-ppe-china/

Of course masks protect people who wear them. Perhaps the protection is "minimal", but that's not zero.

Oh, good grief. So I left out the word "mainly". That in no way refutes my point, which is that this entire discussion has been politicized. And the fact that you are picking at such a tiny nit just further proves my point.

I agree it's been politicized, which is why being precise is important. The fact that medical authorities made claims that blatantly contradict all common sense and basic scientific facts erodes the public confidence. This has happened numerous times since the pandemic began.

I'm Canadian, so I frankly have no direct stake in US politics, but if people on both sides can't agree on basic facts, then there's no hope.

Finally, I don't think the protection afforded is really all that "minimal" for numerous reasons, but the degree of protection wasn't the main thrust point of my post so I didn't (and still don't) want to go into it.

I didn't (and still don't) want to go into it.

And yet you just did.

in the US, at this point, advocating for metrification is associated with a sort of odd, fringe type of political figure.

See the recent presidental campaign of Lincoln Chafee. Or the very humorous "Stonecutters' Song" from the Simpsons (https://www.youtube.com/watch?v=QoSLiHKrzRU), in which a parody of the Freemasons confesses to covering up UFOs, sabotaging electric cars, and suppressing the metric system.

Everything is already made to imperial, people are already comfortable using imperial. And the US is in an international position of strength in that we arent manufacturing amd selling things to other countries, we are buying goods made elsewhere, so we're the ones generating the demand. We dont need to standardize with the rest of the world in the same way, and so we dont bother with the effort. In the areas where standardization is required, such as research and development, you'll see that scientists already use metric.

The US actually originally planned to use metric, but if I recall correctly, the guy thomas Jefferson had invited to bring metric standards to the US ended up getting captured by pirates, so we never had the standards needed to switch and just didnt bother. But he time metrification was sweeping the globe, we'd already industrialized.

And one advantage that imperial has over metric - there are more multiples of 12. 12 is more divisible. A third of a foot is 4 inches, while a third of a meter is 33.333333333333333 etc centimeters

I never get this point. Why does it matter that 100 is not divisible by 3? What makes a third of a metre so special compared to 3 tenths? Most things do not want to fit neatly on integers on one scale, you need decimal points anyway.

In general contexts, either 30, 33, or 35 cm are perfectly acceptable. When accuracy is required, we use millimetres anyway (or micrometres, or nanometres, or angstroms...).

I really don’t see how more integers factors is an advantage that outweighs the clusterfuck that are conversion factors between points, inches, feet, miles, and the other stupid units, or the fact that a nautical mile is not a mile.

Besides, there’s absolutely nothing stopping anyone from using “a third of a metre” as a unit. For example, it’s common to have a line for 1/3 l in measuring cups.

Divisibility.

Using base-ten units, you can divide precisely by only 2 and 5. Not only are 1/3 and 2/3 not integer subdivisions of ten, they're not even precise decimals, but asre repeating.

Under base 12, there are precise subdivisions of 2, 3, 4, and 6 units. Under base 30 you can evenly divide by these as well as 10 and 15.

Under base 60 (a commonly used measurement base, a usage example will come to you in time), subdivisions are the above, plus 12, 20, and 30.

For practical use and arrangement, these can be highly useful capabilities.

In angular measure (base 360, 60*4), there are divisions which relate to trigonometric functions but not decimal scales. And to truly transcent the rational there are radian measures based on pi.

Under metric, you can still come up with precise divisibility, but only by disposing of the base-ten rationality. E.g., using 60cm or 60kg as a division basis.

Ultimately, base ten is an arbitrary anatomical accident.

Base 100! should make you happy. It's divisible by pretty much any integer you'd ever need. A bit unwieldy, but it really cuts down on fractions.

That's factorial, not emphatic notation.

Care to write the proposal?

After some reflection, I was actually thinking we should maybe use base 100!π³ just in case people end up working with spherical volumes. Open to suggestions.

the advantage you sight is exactly problem why the international foot and U.S. survey foot exist and the issue mentioned in article happens.

it may be easy for us to think in fractions with repeating decimals, or irrational numbers ,it is super hard for computers which do Floating Point arithmetic, fractional arithmetic is not common from assembly, higher languages, or libraries we typically use to develop apps.

This is why engineering is always in SI, and errors happen in the interface between people refusing to change,

Given that most computing well happens in computers, It is lot more convenient for us change to a system computers understand, rather than keep a system we understand

engineering is always in SI

Sadly several significant NASA failures would disagree.

a system computers understand

Um, what? Computers understand base 2 (or 16 for compactness), not base 10. A centimeter is not 0.00999999977648258209228515625 meters.

Computers can be made to understand base 10 though, if needed. We do so routinely when amounts of money are involved so a cent is a cent, even though 1/100 is nonterminating as a binary fraction.

Brings up someone I read from an old crusty programmer, binary floating point is the wrong tool for most things. It's fine for scientific simulation work. But for everything else it causes no end of problems.

In the US, only building components are still Imperial measurements. US-made cars and aircraft have been hard metric for decades. Everything imported, other than building components, is hard metric.

Outside the US, almost nobody has non-metric tools. So Imperial stuff is unacceptable for export.

Home Depot creates the illusion that the US is mostly Imperial. They don't stock metric fasteners. One day I was in a Home Depot on a Sunday, and a Chinese woman was desperately looking for some screw she needed to repair some crucial appliance in her restaurant. It was metric, of course, and Home Depot didn't have an ordinary metric screw.

It has ceased to matter. Most new products sold in the US use metric fasteners. A typical family has little or no use for imperial tools. There are some weird hold-out standards such as spark plug wrenches, but those have only one use anyway.

The imperial units are all defined in terms of metric units. There's no standard inch sitting in a vault somewhere.

Machine tools can switch from one to the other in a jiffy. Most design drawings give both units.

There are some odd things that still come in imperial units such as building materials, but a "2x4" is anything but 2 x 4 inches. Plywood is imperial length, but metric thickness, rounded to the nearest convenient inch fraction.

Food still uses imperial units of measure, most of the time, but people just eyeball the quantities and probably don't even know the actual amount. Most people can't look at a container and tell you if it's a pint or a quart.

I believe what happened is that the metric system was taught as a bunch of math, and people hate math. The big push came while I was in grade school, and I remember being taught: "The metric system is easy, all you have to do is some math." Metric was math and conversion factors. I remember a machinist telling me: "I hate metric because of the math." Yet he could add fractional inches in his head.

Is it just older people in the US who want to keep using customary units? Does the younger generation use metric and they'll switch over time?

I don't think I'd have the mental arithmetic required to calculate things in terms of sixteenths!

It’s just a hassle to switch things when you have a large number of people who have adopted it. Even the UK which is nominally metric hasn’t had the will to switch from miles to kilometres for road speeds and distances. The slow spread of globally used volumes is probably the only way it’s ever going to happen and even there it won’t affect most areas.

There does also seem to be a more extreme reluctance in the US to change to more widely adopted units and conventions (e.g. day/month/year) and if anything being one of the only countries left using non metric units seems to be a point of pride. About the only SI units the us seem to use relate to fields invented after science as a whole adopted it as standard (e.g. electrical units).

In one sense inches have a pleasant form of being subdivided into more easily divisible Power of two units but even that falls apart over small distances where they turn to ‘thousandths of an inch’ rather 1024ths. Useful in a world of pre-computer drawing because you could easily scale up plans but not particularly useful now.

Exactly. Drill sizes and, even worse, screw sizes drive me crazy. It's not even obvious which one is larger without doing math.

This reminds me of the great Mythbusters who, to me, came across a bit stubborn to insist on US units -- it felt unsciency. I do understand that they wanted to use the 'normal' system that 'normal' people use -- I always recalculated all their psi and inches of mercury and fathoms per fortnight to SI.

So weird!

I'm a big fan of converting to Celsius. It would probably be the cheapest thing to switch to.

Kilometers? We have more than four million miles of road in the US, and lets rough-guess at the VERY least two speed signs each mile, one each direction. The real number on average is probably double that.

Then there are "mile markers" and every freeway sign that lists distance by miles.

Then there are cars that don't have highly visible kM speedometer markings.

Specific industries may shift to metric, and surely things like surveys probably could. But the total conversion? I would bet on many structural changes in the United States before that ever happens.

Voting reform, Constitutional amendments, DC and PR statehood, banning reality TV, all seem more likely than moving to metric.

Honestly, there's probably less justification in switching to Celsius than other units. Pretty much the only place Fahrenheit really falls down is that it's different from the rest of the world--and the vast majority of Americans are not exposed to that difference on a day to day basis.

Yes, you need to remember what the rather arbitrary seeming freezing and boiling temperature of water are, but that's not a big deal. And you actually get a finer grained measurement system without resorting to decimals. And you're less likely to need negative numbers for ordinary temperatures. (And, if you do, you know it's really really cold.)

Finally, while the Celsius degree size is used in a lot of technical calculations, the absolute scale isn't usually. Kelvin is used instead. So if anything were the "right" unit to use it would be Kelvin, but that would be fairly obviously silly for day to day use.

In my field of research (condensed matter Physics and Thermodynamics), the split between Kelvin and degrees centigrades is about 50%. Anything that gets in contact with industry tends to use °C for some reason.

We were switching to metric in the 70s but Reagan reversed the process, "to own the libs" before that phrase had been created.

https://en.wikipedia.org/wiki/United_States_Metric_Board

How about the inch. I know when you say your height, in US, you use feet + inches. And inch is defined also in regards to meter (2.54 cm) but also in regards to foot (12 inches == one foot). The what kind of foot is used, and does the inch then varies in length as well?

Should switch the foot to a light-nanosecond so all those quick engineering estimates could be the actual length.

Why not use the meter?

Lot of "why not metric" comments. Heres what I think is the main reason: it's just not worth the effort. The US isn't missing out on tangible benefits from not standardizing with the rest of the world. Where it matters in science, we already use metric. Day to day, who cares? Why go through all the trouble to switch? You need people to retrain with a new system, retool signs and equiptment, and so on. It's just not worth it to be able to divide units by 10 more easily, especially when the system we already have is full of powers of 2 or 12 which are frankly a bit easier to divide with day to day (1/3 of a foot is 4 inches, while 1/3 of a meter is 33.33333333.... centimeters). It's just not worth the hassle.

My physics teacher at school told us many times how lucky we were not to have to work in imperial. I'll take his word over yours.

There's a midpoint between science and day-to-day (engineering). Anyway, if you want the US to continue its decline, such a can't-be-bothered attitude will help.

Edit: https://en.wikipedia.org/wiki/Mars_Climate_Orbiter

"However, on September 23, 1999, communication with the spacecraft was lost as the spacecraft went into orbital insertion, due to ground-based computer software which produced output in non-SI units of pound-force seconds (lbf·s) instead of the SI units of newton-seconds (N·s) specified in the contract between NASA and Lockheed."

Some people don't learn.

Who in physics works in imperial? Research is solidly metric in the US.

The mars orbiter loss was due to a failure to perform the necessary checks etc to make sure the mission was on track. Continue reading the section about the failure report. The discrepancy had been noted by humans and had been brought up, but the concerns were ignored because they failed to fill out the correct paperwork, and NASA takes responsibility for the loss, and does not blame lockheed.