why is the US not Metric

[soldar]

~40,000 km is the entire circumference.

Correct. That's the type of mistake that happens when you use American units. 

[KL27x]

From the point of view of someone outside the US, what it seems is that the government tried to convince the people of the benefits of a modern system of units several times. But the people wouldn't listen, choosing to give ears to localism and other emotional arguments.

Ears or tax money?

The units I have mentioned are exactly that, "many types of Imperial".

Ok, let's say you are right. So when there's only one type of Imperial left standing, this problem no longer exists. Last I checked there's a single imperial that matters. Since the UK went metric, we can forget about british pints.

All of the significant problem have been a dead horse for at least 60 years, since global recognition of a single imperial system that is defined by a metric standard, in 1959. The other stuff is just a curiosity, unless you work in the gold industry. The last imperial standing is completely plug and play with metric. US is compliant with international standards regarding imperial, agreed upon in 1959, if and when it uses imperial.

[Tepe]

Since the UK went metric, we can forget about british pints.

The publicans and regulars might disagree with that

[tooki]

From the point of view of someone outside the US, what it seems is that the government tried to convince the people of the benefits of a modern system of units several times. But the people wouldn't listen, choosing to give ears to localism and other emotional arguments.

The only place where citizens gave a crap was miles. But it’s absurd to think that people care about anything else. Consumers don’t care what fasteners their car uses. They don’t care whether a large beer is 16oz or 500ml. They don’t care whether the IV line they get in the hospital is 1m or 3 feet long. They don’t care whether their phone is 5” tall or 12cm.

Now, mechanics and others in the industry care. But nobody else does.

As long as products are fit for purpose and work with the items they need to, people don’t care. Almost nobody has some kind of emotional connection to the units used.

[bsfeechannel]

The only place where citizens gave a crap was miles. But it’s absurd to think that people care about anything else. Consumers don’t care what fasteners their car uses. They don’t care whether a large beer is 16oz or 500ml. They don’t care whether the IV line they get in the hospital is 1m or 3 feet long. They don’t care whether their phone is 5” tall or 12cm.

Now, mechanics and others in the industry care. But nobody else does.

As long as products are fit for purpose and work with the items they need to, people don’t care. Almost nobody has some kind of emotional connection to the units used.

Cool! Since no one cares, change to metric and bury this imperial rubbish deep down in the ground.

[soldar]

All of the significant problem have been a dead horse for at least 60 years, since global recognition of a single imperial system that is defined by a metric standard, in 1959. The other stuff is just a curiosity, unless you work in the gold industry. The last imperial standing is completely plug and play with metric. US is compliant with international standards regarding imperial, agreed upon in 1959, if and when it uses imperial.

The American system of measures is not the Imperial system. They are different. Gallons, threads, etc. Different.

[bsfeechannel]

All of the significant problem have been a dead horse for at least 60 years, since global recognition of a single imperial system that is defined by a metric standard, in 1959. The other stuff is just a curiosity, unless you work in the gold industry. The last imperial standing is completely plug and play with metric. US is compliant with international standards regarding imperial, agreed upon in 1959, if and when it uses imperial.

Man, don't you know how to use the Quote button?

Anyway, the inch, the foot, the pound, the ounce, etc. are not metric units. They are not defined in that system. There are international agreements about their conversion rates, but it stops there. So, no, the imperial system is not plug and play with the metric system. Imperial is just a free-loader to the metric standards, because if imperial additionally had to define its own standards, it would be a second level of stupidity in a globalized economy.

Although the American imperial is the only major customary system in use today, since all the other nations converted to metric, the American imperial is the new English pint.

[tooki]

The only place where citizens gave a crap was miles. But it’s absurd to think that people care about anything else. Consumers don’t care what fasteners their car uses. They don’t care whether a large beer is 16oz or 500ml. They don’t care whether the IV line they get in the hospital is 1m or 3 feet long. They don’t care whether their phone is 5” tall or 12cm.

Now, mechanics and others in the industry care. But nobody else does.

As long as products are fit for purpose and work with the items they need to, people don’t care. Almost nobody has some kind of emotional connection to the units used.

Cool! Since no one cares, change to metric and bury this imperial rubbish deep down in the ground.

Tons of stuff has switched, and tons more will. Some things likely never will, and I’ve explained the reasons for NOT switching multiple times, just scroll up and read.

[bsfeechannel]

Tons of stuff has switched, and tons more will. Some things likely never will, and I’ve explained the reasons for NOT switching multiple times, just scroll up and read.

Oh, well. The US are hopeless. What comforts me is that in a parallel universe the world adopted imperial and the US metric. And now the parallel US are pissed because the imperial volt, ohm, watt, joule, farad, henry, and all other units used in electronics are defined by imperial, and they have odd conversion rates, so when people travel abroad they don't have the slightest idea how 3000, 4000 or 5000 imperial volts translate to the metric volt and have to resort to calculators or rules of thumb to know it.

V = kg m²/A s³ = 2.2lb · (3.28)²ft² / A s³
Ω = kg m²/s³A² = 2.2lb · (3.28)²ft² / s³A²
W = kg m²/s³ = 2.2lb · (3.28)²ft² / s³
J = kg m²/s² = 2.2lb · (3.28)²ft² / s²
F = s⁴A²/ kg m² = s⁴A² / 2.2lb · (3.28)²ft²
H = kg m² /s²A² = 2.2lb · (3.28)²ft² / s²A²

2.2lb · (3.28)²ft² approx. 23.7 lb · ft²

1 V = 23.7 iV
1 Ω = 23.7 iΩ
1 W = 23.7 iW
1 J = 23.7 iJ
1 F = 0.0422 iF
1 H = 23.7 iH

Let's admit it: imperial is RE-TAR-DED (and probably contagious).

[soldar]

Although the American imperial is the only major customary system in use today, since all the other nations converted to metric, the American imperial is the new English pint.

I believe it is not called American Imperial but American Customary.

[MagicSmoker]

I believe it is not called American Imperial but American Customary.

Technically true, but I doubt you'll find many Americans that say they use the Customary system, and I always refer to it as Imperial - especially here - because that seems to be universally recognized, especially by non-US people.

[tooki]

Let's admit it: imperial is RE-TAR-DED (and probably contagious).

Arrogant much?

[forrestc]

There is one point some are missing about why specific non-SI units stick around...

Inertia.

Let me give you an example:

In the US all of the freeway systems are labeled in miles, the exits are numbered based on miles, the highway signs are in miles.     

Well, except one.   Interstate 19 is labeled in Metric.  All the distance signs are in meters or km, the exits are numbered by km, and so on.    Why?   Because it was re-labeled during the push for metrification back in 1980, and no one has seen any reason to change it back to miles.  There apparently were some plans to switch it back to miles, but the locals revolted because of the trauma caused by changing from km back to miles due to the exit numbers changing, etc.

There are so many things that are hard to change because of the trauma which is related to the changeover.   Things as simple as switching the screws which hold on a switch cover plate means that all of a sudden, you have to stock and deal with both the new and old styles.   And for things like this, it doesn't really matter.  It could even be something totally oddball just for that application, and it still would be ok.

Take, for instance, the example of Interstate 19.   One main reason why they haven't switched back is the cost of replacing all of the signs at once.   If replacing the signs on 100k of Interstate is cost-prohibitive, imagine the cost of doing so along the 6.5 million kilometers of roads we have in the US.   And, there really isn't any downside to staying metric as most people rarely ever cross into a metric country.  The only difference in a modern automobile is the display units on the speedometer/odometer. Even that is moving toward being universal due to the trend to move away from a mechanical speedometer and odometer to a digital display.

So, if you look at the stuff that the US hasn't converted, almost all of it fits into this category:  Stuff so deeply entrenched into the daily lives that it would be painful to change over.   Or stuff that the units don't really matter for.

[Altair8800]

There is one point some are missing about why specific non-SI units stick around...

Inertia.

Let me give you an example:

In the US all of the freeway systems are labeled in miles, the exits are numbered based on miles, the highway signs are in miles.     

Well, except one.   Interstate 19 is labeled in Metric.  All the distance signs are in meters or km, the exits are numbered by km, and so on.    Why?   Because it was re-labeled during the push for metrification back in 1980, and no one has seen any reason to change it back to miles.  There apparently were some plans to switch it back to miles, but the locals revolted because of the trauma caused by changing from km back to miles due to the exit numbers changing, etc.

There are so many things that are hard to change because of the trauma which is related to the changeover.   Things as simple as switching the screws which hold on a switch cover plate means that all of a sudden, you have to stock and deal with both the new and old styles.   And for things like this, it doesn't really matter.  It could even be something totally oddball just for that application, and it still would be ok.

Take, for instance, the example of Interstate 19.   One main reason why they haven't switched back is the cost of replacing all of the signs at once.   If replacing the signs on 100k of Interstate is cost-prohibitive, imagine the cost of doing so along the 6.5 million kilometers of roads we have in the US.   And, there really isn't any downside to staying metric as most people rarely ever cross into a metric country.  The only difference in a modern automobile is the display units on the speedometer/odometer. Even that is moving toward being universal due to the trend to move away from a mechanical speedometer and odometer to a digital display.

So, if you look at the stuff that the US hasn't converted, almost all of it fits into this category:  Stuff so deeply entrenched into the daily lives that it would be painful to change over.   Or stuff that the units don't really matter for.

Not all USA states have their highway exit signs in sync with mile markers.  So in one state I lived in, they did a switch.  So for a few years (maybe 2-3) they had signs that said in big print [ EXIT 128 (old exit 27) ].  Then after about 3 years they just got rid of the (old exit 17).  It was a pretty good phase in.

Another example of a phase in...  Is sidewalks and street curbs...  In the old days the corners street curb height was about 15 cm (6").  These are not friendly to people in wheel chairs (or handicap scooters) or kiddy bicyclists.  So they wanted to change but not have to change hundred/thouthands at a time.  So the compromise they would stretch the budget over several years.  If a road had major roadwork those roads would get new sloped handicap friendly curbs.  In addition to that, they also changed a certain amount of curbs per year (so it would not take forever to get the curbs done).  So after 15-20 years all the curbs would be changed.  So you can also phase things in slowly.

[bsfeechannel]

Let's admit it: imperial is RE-TAR-DED (and probably contagious).

Arrogant much?

Maybe you're right. I don't want to be a metric rstofer. The thing is that... it is so nice to work with metric for everything that I go a little overboard.

[Altair8800]

To our non-American friends...   

This is an example of what a typical American would and not know about our American Customary/Imperial measurement system.

Most Americans would know the following:

• there are 12 inches [in] in 1 foot [ft]
• there are 3 feet [ft] in 1 yard [yd
• there are 36 inches [in] 1 yard [yd
• there are 2 half gallons in 1 gallon [gal
• there are 4 quarts [qt] in 1 gallon [gal
• there are 16 ounces [oz] in 1 pound [lbs]

Some Americans might or might not know:

• there are 3 teaspoons [tsp] in 1 tablespoon [tbsp]
• there are 8 pints [pt] in 1 gallon [gal]
• there is a Fluid Ounce [fl oz] and a Pound Force Ounce [oz]
• there is 8 fluid ounces [fl oz] in 1 cup [cup]

Most Americans would not know (without looking up):

• there are 16 cups [cup] in 1 gallon [gal]
• there are 128 fluid ounce [fl oz] in 1 gallon [gal]
• there are 8.345 pounds [lb] in 1 gallon [gal] of water {or ~milk]
• there are 1.04 ounce [oz] in 1 fluid ounce [fl oz] of water
• there are 256 tablespoons [tbs] in 1 gallon [gal]
• there are 16 tablespoons [tbs] in 1 cup
• there are 231 cubic inches [in^3] in 1 gallon [gal]
• there are 7.481 gallons in 1 cubic foot [ft^3]
• there are 27880000 square feet [ft^2] in 1 square mile [mi^2]
• there are 43560 square feet [ft^2] in 1 acre
• there are 1760 yards [yd] in 1 mile [mi]
• there are two types of pounds, a pound mass (lbm) and a pound force(lbf)
• there are 32.1740 pounds [lb] in 1 slug {used to define Pound Force}
• there are 14 pounds [lb] in 1 stone [st] {used a lot in UK but almost all Americans do not know}
• there are 42 gallons [gal] in 1 barrel {think oil or whiskey }
• 1 horsepower is amount of work to lift 550 pounds 1 foot up in 1 second {commonly used to describe power}
• that a USA cup can be either 8 fluid ounces OR 8.115 fluid ounces {think USA Legal cup is 240ml = 8.115 fl oz}

Edits:  Mostly just corrected incorrect units that I found myself and two that vk6zgo found.  Also corrected typos and spelling mistakes.  Also note, the above are in US Customary Units which are Imperial-ish units that have been slightly changed to closer match metric equivalent units over the years.  In the USA, we significantly (and lazily) call our units Imperial when they really are not.

[soldar]

I believe it is not called American Imperial but American Customary.

Technically true, but I doubt you'll find many Americans that say they use the Customary system, and I always refer to it as Imperial - especially here - because that seems to be universally recognized, especially by non-US people.

American and Imperial are different systems of units and saying Imperial when you mean American is wrong and can lead to confusion.

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

An Imperial gallon is different from an American gallon.

[Altair8800]

I believe it is not called American Imperial but American Customary.

Technically true, but I doubt you'll find many Americans that say they use the Customary system, and I always refer to it as Imperial - especially here - because that seems to be universally recognized, especially by non-US people.

@bsfeechannel
I understand and know they are not the same...  But in USofA we rarely say US Customary Units.  We actually would more often say Imperial units (even though we mean US Customary Units).  I was trying to bridge the gap by saying both... 

[MagicSmoker]

Technically true, but I doubt you'll find many Americans that say they use the Customary system, and I always refer to it as Imperial - especially here - because that seems to be universally recognized, especially by non-US people.

American and Imperial are different systems of units and saying Imperial when you mean American is wrong and can lead to confusion.

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

An Imperial gallon is different from an American gallon.

I didn't say Imperial was correct, I said it was what most Americans are likely to answer if you asked them what kind of measuring system they use. If they even know of a name in the first place, that is. Don't let the perfect be the enemy of the good and all that.

[tooki]

Let's admit it: imperial is RE-TAR-DED (and probably contagious).

Arrogant much?

Maybe you're right. I don't want to be a metric rstofer. The thing is that... it is so nice to work with metric for everything that I go a little overboard.

Fair enough.

For what it’s worth, I’m American, and like many Americans (especially younger and/or nerdier ones), I’m quite conversant in both systems, and basically cherry-pick them situationally. I find metric easier to work with for many (probably most) things, but others I prefer customary. (For example, I use Celsius for cooking, but Fahrenheit for ambient temperature. If I’m laying out a document for US Letter paper, I’ll set the program to use inches, if I’m laying out for A4, I set it to metric. And many more things I really don’t have any meaningful personal preference, so absent some other reason to choose one or the other, I’ll use the system of whatever location I’m in, since it’s more likely to be what products are marked with and other people are familiar with.)

Another weird little thing I just thought about: US customary mostly uses inches divided fractionally in powers of 2. In a way, works really well because it’s easy to shift how much granularity you need without necessarily adding tons of digits. But then in electronics, the normal spacing has been 0.1”, which doesn’t align with the powers-of-2 fractions. That’s just as annoying as making 0.1” spacing play nice with metric! :p

[soldar]

I didn't say Imperial was correct, I said it was what most Americans are likely to answer if you asked them what kind of measuring system they use. If they even know of a name in the first place, that is. Don't let the perfect be the enemy of the good and all that.

Oh, I agree with you that the average person in the street is quite ignorant and expresses themselves poorly.

On the other hand, when talking in technical terms it is important to use the correct terms.

This happens in every specialized field. In law, terms, crimes, etc. have very precise definitions but people use terms loosely and, very often, wrongly.

[vk6zgo]

To our non-American friends...   

This is an example of what a typical American would and not know about our American Customary/Imperial measurment system.

Most Americans would know the following:

• there are 12 inches [in] in 1 foot [ft]
• there are 3 feet [ft] in 1 yard [yd
• there are 36 inches [in] 1 yard [yd
• there are 2 half gallons in 1 gallon [gal
• there are 4 quarts [qt] in 1 gallon [gal
• there are 16 ounces [oz] in 1 pound [lbs]

Some Americans might or might not know:

• there are 3 teaspoons [tsp] in 1 tablespoon [tbsp]
• there are 8 pints [pt] in 1 gallon [gal]
• there is a Fluid Ounce [fl oz] and a Pound Force Ounce [oz]
• there is 8 fluid ounces [fl oz] in 1 cup [cup]

Most Americans would not know (without looking up):

• there are 16 cups [cup] in 1 gallon [gal]
• there are 128 fluid ounce [fl oz] in 1 gallon [gal]
• there are 8.345 pounds [lb] in 1 gallon [gal] of water {or ~milk]
• there are 1.04 ounce [oz] in 1 fluid ounce [fl oz] of water
• there are 256 tablespoons [tbs] in 1 gallon [gal]
• there are 16 tablespoons [tbs] in 1 cup
• there are 231 cubic inches [in^3] in 1 gallon [gal]
• there are 7.481 gallons in 1 cubic foot [ft^3]

• there are 5280 square feet [ft^2] in 1 mile [mi]

Oops! Better get that editing pen out again!

• there are 43560 square feet [ft^2] in 1 acre
• there are 1760 yards [yd] in 1 mile [mi]
• there are two types of pounds, a pound mass (lbm) and a pound force(lbf)
• there are 32.1740 pounds [lb] in 1 slug {used to define Pound Force}
• there are 14 pounds [lb] in 1 stone [st] {used a lot in UK but almost all Americans do not know}
• there are 42 gallons [gal] in 1 barrel {think oil or whiskey }
• 1 horsepower is amount of work to lift 550 pounds 1 foot up in 1 second {commonly used to discribe power}
• that a USA cup can be either 8 fluid ounces OR 8.115 fluid ounces {think USA Legal cup is 240ml = 8.115 fl oz}

[boffin]

1 US Gal of 100LL weighs 6lbs; except I buy it in litres

[Altair8800]

1 US Gal of 100LL weighs 6lbs; except I buy it in litres

In my previous list I was going to put...

• there are 8.345 pounds [lb] in 1 gallon [gal] of water {or ~milk or ~gasoline]

But then did a quick Wolfram Alpha search on density of gasoline to find to my surprise that gasoline is a good bit less dense than water.

726 kg/m^3

so I did not add the ~gasoline part

Also FYI the density of milk is 1100 kg/m^3 and of course density of water is 1000 kg/m^3

[KL27x]

If the math is correct, it's almost as if units don't matter, as long as they are used, correctly. Weird how that works. It's almost as if the math is empirical and the units are simply a human-arbitrated point of calibration/reference.

When we encounter aliens, we shall have to inform them their units of measurement are retarded and they should switch to metric.

None of the non "American customary" units are in use, anymore, to my knowledge, other than troy oz's in the gold industry, definition of foot in land surveying, and pints in a british pub. But if anyone wants to add something that isn't ancient history, feel free to show us where Americans are using slugs and stones and confusing tower oz and imperial gallons. There are probably "old units" used in farming still, in many countries for estimating weight of stuff in the field. But that is not anyone's concern other than the farmer.

Let's correct the direction of conventional current while we're at it.