4 ms·

There's a couple of things you'd want to consider converting to metric: long distances, short distances/dimensions, volumes, weights, and temperature come to mi

There's a couple of things you'd want to consider converting to metric: long distances, short distances/dimensions, volumes, weights, and temperature come to mind. Long distances: swap out a bunch of highway signs, consider that 60mph (a mile a minute) ~= 100km/h, not too hard on people but a lot of signage needs to change. Feasible. Volumes: people are used enough to 2-liter bottles of soda, expect the 3.78 liter milk to stay around for a while because of supply chains. Gas prices will be modestly interesting for people, but really easy on the industry. Short distances/dimensions: now things get tricky and potentially expensive. There are a lot of fractional-dimensioned parts out there in industry in different supply chains. Weights: 2.2lb = 1kg and you're pretty good. Nobody really uses ounces anyway! Temperature: Here's the thing about temperature: converting would be relatively useless because Real People don't do math with the temperature outside. Even scientists don't do math with the temperature outside all that much. For most people, a scale that starts at 0="civilization shuts down because you can't ice the roads" and goes up to 100="heatstroke territory" is a fine representation of humanity's day to day temperature. Why would we bother changing it?

bruceboughton 14y ago
> For most people, a scale that starts at 0="civilization shuts down because you can't ice the roads" and goes up to 100="heatstroke territory" is a fine representation of humanity's day to day temperature. Why would we bother changing it? I thought you were talking about Celsius at first...
sterna 14y ago
Mecanical parts are the most difficult thing to switch because there are many things defined in relation to one another. For example the american UNC threads have different angles than the metric ones do and therefore it is impossible to replace one with another. For this reason alone it will take very long time to do a full switch from one unit system to another. However, many "metric" units are actually slightly adapted imperial ones. For instance you can get a lot of 25 mm stuff in Europe that is almost equivalent to the 1 inch stuff you get in the US (1 inch = 25.4 mm) and similarly there is a lot of 30 cm and 60 cm stuff in stead of 1 foot and 2 feet stuff.
smackfu 14y ago
>not too hard on people but a lot of signage needs to change. Feasible. Very expensive though. Signs normally have a 20 years expected lifetime. Now you need to replace them all at once. Plus a lot of the sign locations need to be changed, unless you want all those "Exit 29 1 mile" signs to now say "Exit 29 1.6 km".
- jzwinck 14y ago
  You do not need to replace them all at once. For example the new signs could be European style, red ringed white circles with the number inside. Virtually every car has both readings already. This would make new speed limit signs immediately recognizable to more visitors in the future while avoiding ambiguity of units during the transition. They could even say km/h during the first generation.
  - DanBC 14y ago
    Road signs need to be very clear and instantly understandable. Adding a tiny delay to comprehension; a tiny bit of lack of attention to the road; could, when multiplied over the number of kilometres driven and number of drivers and time mean many deaths. Whether that's acceptable or not is another matter, but it'd suck if "km/h KILLED MY FATHER" became a meme. It is odd how some countries make massive national changes overnight. eg, Sweden: (http://users.telenet.be/worldstandards/driving%20on%20the%20left.htm http://users.telenet.be/worldstandards/driving%20on%20the%20...) > In 1955, the Swedish government held a referendum on the introduction of right-hand driving. Although no less than 82.9% voted “no” to the plebiscite, the Swedish parliament passed a law on the conversion to right-hand driving in 1963. Finally, the change took place on Sunday, the 3rd of September 1967, at 5 o’clock in the morning. Leaving it until now has meant the UK would find it very hard to change.
- e1ven 14y ago
  Why not phase things in, by having both measurements put on, for all new signs? Exit 14 - 1 Kilometer (.6Miles) Then, as the old signs wear out, eventually all signs are replaced.
TylerE 14y ago
The devil is in the details. In the US, all speed limits are in 5 mph increments. So, let's say you convert your 60mph limit to 100kph (Really 96.5). 70mph is 112.65kph. Do you round down to 110, or up to 115 or 120? If you round down, congratulations, you just cut the speed difference between a rural highway and interstate essentially in half, as a "true" 17kph difference is only 10.
stephen_g 14y ago
Anyone in a country that uses the celsius scale knows that the temperature argument is rubbish... It's totally and completely what you're used to. I doubt people really think of temperature in more than about eight or ten increments anyway (bloody freezing, cold, pleasant, etc.) so having a range of forty or fifty integers really gives you more than enough precision. I suppose it doesn't really matter what people use to express the temperature in common use, but having a unified scale across ambient temperature, cooking, science (1K = 1°C), manufacturing, etc. that people in almost every other country uses really does make sense, especially when the conversion is so annoying.
- fennecfoxen 14y ago
  My point is more "why should people have to change what they're used to for a small subset of the scientific class?" - of all the things that people do math with, and would benefit from decimalization and metrifying, temperature is pretty much the last.

bruceboughton 14y ago

> For most people, a scale that starts at 0="civilization shuts down because you can't ice the roads" and goes up to 100="heatstroke territory" is a fine representation of humanity's day to day temperature. Why would we bother changing it? I thought you were talking about Celsius at first...

sterna 14y ago

Mecanical parts are the most difficult thing to switch because there are many things defined in relation to one another. For example the american UNC threads have different angles than the metric ones do and therefore it is impossible to replace one with another. For this reason alone it will take very long time to do a full switch from one unit system to another. However, many "metric" units are actually slightly adapted imperial ones. For instance you can get a lot of 25 mm stuff in Europe that is almost equivalent to the 1 inch stuff you get in the US (1 inch = 25.4 mm) and similarly there is a lot of 30 cm and 60 cm stuff in stead of 1 foot and 2 feet stuff.

smackfu 14y ago

>not too hard on people but a lot of signage needs to change. Feasible. Very expensive though. Signs normally have a 20 years expected lifetime. Now you need to replace them all at once. Plus a lot of the sign locations need to be changed, unless you want all those "Exit 29 1 mile" signs to now say "Exit 29 1.6 km".

jzwinck 14y ago
You do not need to replace them all at once. For example the new signs could be European style, red ringed white circles with the number inside. Virtually every car has both readings already. This would make new speed limit signs immediately recognizable to more visitors in the future while avoiding ambiguity of units during the transition. They could even say km/h during the first generation.
- DanBC 14y ago
  Road signs need to be very clear and instantly understandable. Adding a tiny delay to comprehension; a tiny bit of lack of attention to the road; could, when multiplied over the number of kilometres driven and number of drivers and time mean many deaths. Whether that's acceptable or not is another matter, but it'd suck if "km/h KILLED MY FATHER" became a meme. It is odd how some countries make massive national changes overnight. eg, Sweden: (http://users.telenet.be/worldstandards/driving%20on%20the%20left.htm http://users.telenet.be/worldstandards/driving%20on%20the%20...) > In 1955, the Swedish government held a referendum on the introduction of right-hand driving. Although no less than 82.9% voted “no” to the plebiscite, the Swedish parliament passed a law on the conversion to right-hand driving in 1963. Finally, the change took place on Sunday, the 3rd of September 1967, at 5 o’clock in the morning. Leaving it until now has meant the UK would find it very hard to change.
e1ven 14y ago
Why not phase things in, by having both measurements put on, for all new signs? Exit 14 - 1 Kilometer (.6Miles) Then, as the old signs wear out, eventually all signs are replaced.

TylerE 14y ago

The devil is in the details. In the US, all speed limits are in 5 mph increments. So, let's say you convert your 60mph limit to 100kph (Really 96.5). 70mph is 112.65kph. Do you round down to 110, or up to 115 or 120? If you round down, congratulations, you just cut the speed difference between a rural highway and interstate essentially in half, as a "true" 17kph difference is only 10.

stephen_g 14y ago

Anyone in a country that uses the celsius scale knows that the temperature argument is rubbish... It's totally and completely what you're used to. I doubt people really think of temperature in more than about eight or ten increments anyway (bloody freezing, cold, pleasant, etc.) so having a range of forty or fifty integers really gives you more than enough precision. I suppose it doesn't really matter what people use to express the temperature in common use, but having a unified scale across ambient temperature, cooking, science (1K = 1°C), manufacturing, etc. that people in almost every other country uses really does make sense, especially when the conversion is so annoying.

fennecfoxen 14y ago
My point is more "why should people have to change what they're used to for a small subset of the scientific class?" - of all the things that people do math with, and would benefit from decimalization and metrifying, temperature is pretty much the last.