Dambit. It's S.A.E. not Imperial... Right?

Is there a difference between the Imperial measuring system and the S.A.E. (Standard American English) measuring system? The international people (and Americans (and tons of dopers)) I communicate with on the web keep referring to the U.S. measurement system as “Imperial”. I understand that our system of feet and inches comes from England which was once upon a time an empire, but England now uses the Metric system. So now that America is pretty much the only country still using this system and we are not now nor have we ever been an Empire (despite popular opinion), calling it imperial today is no longer accurate, especially since it’s been given a different label. Does anyone know more about the history behind SAE? Did they rename it because of the implied connotation that those who use it are empirical or did they create a new name for it because there are real differences between SAE and Imperial?

The U.S. measuring system is “U.S.” The traditional British measuring system, or at least some part of it, is “Imperial.” I only recall hearing the distinction made in reference to liquid volume measurement, i.e. Imerial gallon vs. U.S. gallon.

I’ve never heard the word Imperial applied to measurements used in the U.S. I don’t know where the folks you’re listening to got the idea, but I think you’ll find they’re flat out wrong.

I’ve never heard of “SAE” standing for Standard American English. I suspect you’re thinking of “SAE” as in the Society of Automotve Engineers, whose standards apply to various automotive applications, including some fasteners.

So far as I know there are some differences between U.S. and Imperial measures, such as gallons and tons. However, if you’re just talking feet and inches, then I think you’re nit-picking a bit.

Many of the units are subtly different (I think that the American definition of the mile differs from the Imperial definition by a few millimeters, though I can’t find a cite), but in most cases, it’s a small distinction. The big contrast is in liquid measure: For the pint and all larger units, the Imperial value is 25% larger than the American (so in both cases, there are two pints in a quart and four quarts in a gallon, but the Imperial pint is 20 oz compared to the American 16 oz). Teaspoons and tablespoons are also different, but I can’t remember how much either of them is in either system. This is one major advantage of the metric system: Anywhere in the world, if someone refers to a liter, they mean the same thing.

And the US may be the most non-metric nation, but non-metric units are still widely used elsewhere. In Ireland, for instance, the speed limit signs are all in mph, not kph, and they don’t even list the units on the sign, just the number.

Gary T is right - SAE means “Society of Automotive Engineers.” You see it mainly on tools as far as I know.

The US standard system existed and was enshrined by law before the Imperial System was invented. The Imperial System was invented in the 19th century, after US independence. Likewise, the US inch was longer than the Imperial inch. All this changed in 1959, when both were redefined to be exactly 2.54cm, which required introducing the “Survey Inch”, which was the old inch used in all the old surveys.

Not for very much longer…

This is clipped from another forum, and I have seen it on Google groups (OK, USENET) roat.transport too…

Right now we still use miles and mph, but we’ve been phasing in metric units in supermarkets and so on, and we sell petrol in litres. Beer is still sold in pints (20oz pints, of course!).

In science classes in school, we were using SI (Systeme Internationale) units - metre/kilogram/second and derivations - back in the 1970s.

More than you want to know about old fastening systems on cars and planes