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1970-01-01

London will switch sides when America goes metric - i.e. never.

The US is on the metric system: The official definitions of US customary units are in metric.

For example: https://www.regulations.gov/document/NIST-2019-0003-0001

> After December 31, 2022, any data derived from or published as a result of surveying, mapping, or any other activity within the U.S. that is expressed in terms of feet shall only be based on the “foot” equal to 0.3048 meter (exactly), formerly known as the “international foot” in the 1959 Federal Register notice.

The US uses the metric system in some places, but that is not to say it is "on the metric system"- after all, all road speed limit signs are still in miles per hour, as an example. Fuel is priced in dollars per gallon. Consumer goods are almost always sold in measurements of pounds, ounces or gallons. People are measured in feet, inches and pounds on their ID cards and at doctor's offices.

Metric has made almost no inroads at all in anyone's daily life here.

I believe their point is that a mile is defined to be exactly 1609.344 meters, a gallon is defined to be exactly 3.785411784 litres, a pound (mass) is defined to be exactly 453.59237 grams and so on. These are all just weird multiples of metric units at this point.

Eh, I seriously doubt that we will be changing the distance a mile represents if, for some bizarre reason, a meter gets redefined. Likewise, pounds and gallons and so forth. These measurements "defined in metric" is really more of a "formal conversion rate" ala converting between degrees F and C.

> if, for some bizarre reason, a meter gets redefined

Miles, feet and yards were tied to the meter in 1893 (https://en.wikipedia.org/wiki/Mendenhall_Order).

The meter got redefined 3 times since then (https://en.wikipedia.org/wiki/History_of_the_metre#Summary_o...)

It would be way more annoying for LHT countries to change to RHT than to switch from US units to metric, have to change literally every road sign, street light, road markings etc in the entire country.

Plus everyone would then be driving cars with the steering wheel on the wrong side for decades until the whole fleet got eventually replaced.

Countries have done it before, but I think there's a reason not many countries have done it since the mid 20th century when roads and cars were a lot simpler and there were fewer of them.

Switching to metric could be done gradually - replacing existing signs with metric ones only when they wear out, building new systems in metric while still using US units for the old ones.

There's no way to gradually switch from LHT to RHT, you have to somehow do a switchover in a day

> It would be way more annoying for LHD countries to change to RHD

As a complete aside, 1 country has done this: Sweden on 3 September 1967 and "It was by far the largest logistical event in Sweden's history"

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

Iceland did it a year later, https://en.wikipedia.org/wiki/H-dagurinn, but since there was less then 200k people living there it was a much less dramatic change

Falkland Islands did it for a brief second, though not by choice.

IIRC a lot more countries did it but mostly a lot earlier (pre ww2).

Back then it would have been comparatively easy, cars were slow and there were barely any street signs etc anyway

And the US and various other countries (like the UK) effectively use hybrid systems for units for many purposes. Science and engineering in the US are heavily metric.

> There's no way to gradually switch from LHT to RHT, you have to somehow do a switchover in a day

You could do it in phases. Have the trucks switch over on Monday, buses on Tuesday ...

And we would want to do that because......

We can take jokes…

Jim Davidson has displayed greater wit and comedy.

Who is Jim Davidson when he's at home?

Because it would be the cause of much mirth?

I used to think about whether we can get more countries switching back to LHT, but with Autonomous Vehicles that will no longer be much of an issue in 10 - 20 years time.

I am told that Left Hand Drive is marginally safer (all other things being equal) because of the preponderance of right-handed people. Driving on the left of the road places the right-handed driver's dominant hand on the wheel and dominant eye towards the centre of the road and oncoming traffic.

However this is not an argument in favour of 20th century style, non-autonomous individual vehicles as the main transit solution. There are safer and better ways. Autonomous Vehicles will hopefully play a role in that.

You'd also have things like bus doors now being on the wrong side (traffic-side), road curvature being wrong (e.g. motorway junctions and entry/exit ramps), let alone car mirrors and driver positioning.

Once all manufacturing is controlled by China, they could refuse to make cars with steering on the right or use Standard measurements, increasing pressure and eventually forcing the UK and US to switch.

Thank you for informing me that China is likely to take over all manufacturing when it comes to cars. I am appalled that there are no US, Japanese, South Korean, Indian, Vietnamese, Russian, or any other nations that manufacture cars.

It also sounds completely plausible that a binary choice like left hand or right hand driving can be switched in a way that drives a pressure campaign that nations will give into China on because it’s an easier short term choice and wouldn’t gain an immediate reaction to due to the enormous cost that would be rapidly felt.

In the eastern parts of Russia (well even in "central" Russia like Novosibirsk), there's a lot of imported Japanese cars from their second-hand market. These have the wheels "on the wrong side", but nobody cares, they still drive on the right.

It's really annoying have the wheel on the wrong side. Makes it really hard to pull out of parking spaces, or overtake.

Mail carriers in the USA also have their wheel on the other side so they can reach people's mailboxes easily.

The US drives on the right (which is the right) side. So why would the US switch? Its really just Australia, Japan, India and the UK that drive on the left. The other 190ish countries all drive on the right.

PS Your 240V electric grid works that way because when the US switched to 120V (in like 1900 or so), we sold all our old gear to you and you never switched. So now all your electric things cost more as a result and your electrical outlets will kill you. So your decision making on such things is suspect.

Would you care to cite the statistics you have showing higher per-capita accidental electric shock deaths? I'm struggling to find any.

The US has a 240 volt electric system nearly everywhere. The exceptions are some industrial factories that get higher voltage. There might be a handful of houses that haven't upgraded their electric system since the 1950s that are still 120volt only, but that is very rare (I've heard of it, but never seen it). We use 120 volts to outlets (120 is half of 240), but the system itself is 240 volts.

Electric distributon costs less because less copper/aluminum. 120V exists because the US is plagued by lawyers.

Hong Kong drives on the left, mainland China on the right.

And there's a fun little dance where the roads meet.

There are enough standards that don’t have non-metric alternatives like the square drive of socket wrenches or a lot of bicycle standards. It’s very unlikely that they will get replaced

Bicycles are hilarious because the same sizes will be designated in inches or millimeters depending on where or why they are taken. E.g. handlebars are 31.8 mm or 25.4 mm (1¼" and 1") but steerers are 1" or 1⅛". Wheels of the same diameter will be called 28", 29" or 700 (and the diameter is actually 25½" but it's only called "622 mm"). And even when they use metric from the start for something that is not a standard fastener already they end up with things like 28.99 mm spindles (not to be confused with 30 mm spindles, which also exist).

The imperial system America uses is better optimized for quantities people expect to use in real life frequently without requiring awkward decimals or larger numbers etc. better ergonomics.

metric is only for science.

With imperial you have weird fractions instead of decimals. To know that 3/4“ is larger than 1/2“ I have to actively think, decimals come pretty naturally (which was probably different in times before people went to school and learned to do math on paper)

To know that 0.32 m is smaller than 43 cm I have to actively think, but I'm guessing you don't. I've never had to think about 3/4 vs 1/2. Even 5/16ths vs 1/4 is intuitive for me.

https://en.wikipedia.org/wiki/Third-pound_burger

When we use fractions for measurements, the denominator is virtually always a power of two. The only one I can think of that isn't is a fifth of alcohol, which is really just its own unit at this point.

An inch is 1/36 yd or 1/12 ft or 6 pica or 72 pt. There is no power of two whatsoever in this.

Neither 1/36th or 1/12th are used, and the other two aren't fractions. We don't say six and a twelfth feet, we say six feet one inch. With distance, fractions are only used for fractions of an inch (apart from trivial uses like "one and a half miles").

American money is fully metric.

I feel like neither system is inherently better outside of familiarity and I don't care which is used I'm just tired of having to own two sets of tools.

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