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There are apparently TWO standard foot measurements...

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JohnRBaker

JohnRBaker

Mechanical
Jun 1, 2006
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Perhaps some Civil out there can explain this better, but I just learned that there are TWO different standard measurements for a 'foot'. There's the 'International Foot' and then there's the 'US Survey Foot', which apparently is only used by land-surveyors. Anyway, it appears that we're finally going to standardize on the 'International Foot' for ALL measurements in the United States, including surveying. Now the difference is not all that much, over a distance of one mile, it would be about an eighth of an inch (the 'International Foot' is shorter).

Anyway, this was news to me.

US finally giving boot to official foot measurement

The United States is abandoning the definition of the foot used to measure big things and replacing it with the so-called international foot


So if there's any Civil's out there, they can give us their take on this development.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without
 
The international foot was normalized to be exactly 12*25.4 mm, whereas the survey foot was, is 12*25.4000508 mm, which is what we learned in school, coming from 1 m = 39.37 in

Apparently, the international foot existed since a couple of years after I was born, but I remember using the 39.37 in conversion well into high school.



TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! faq731-376 forum1529 Entire Forum list
 
That's just in the USA. World wide there are probably several more.
Wiki said:
Historically the "foot" was a part of many local systems of units, including the Greek, Roman, Chinese, French, and English systems. It varied in length from country to country, from city to city, and sometimes from trade to trade. Its length was usually between 250 mm and 335 mm and was generally, but not always, subdivided into 12 inches or 16 digits.
Click to expand...
Until Honduras changed to the metric system they used an older definition of a foot that did not agree with the Canadian foot.
And why the difference in the USA?
convert-me.com said:
American weights and measures are based on units used in Britain prior to 1826, when imperial system was officially established. Until 1960-1963 American and British units of length were different in 2 parts per million. In the middle of 20th century it started causing problems and the governments of the two countries agreed to refine the measures to exactly match. Since then Great Britain and the United States were using the same measures of length. In the U.S. the old standard of foot was retained with the name US survey foot.
Click to expand...

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Seems bassackwards. The US adopts an international standard for a unit of length which none of the rest of the international world uses.
 
A foot length is always variable specially when describing your fishing trip......

It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
 
I was watching the Presidents Cup (from Melbourne Australia) on TV over the weekend. (Why isn't it President's Cup, with an apostrophe, by the way?) I found it amusing (and annoying) that the event was tailored so strongly for an American audience, even on our Australian host broadcast - hole lengths were given in yards first and meters (sic) second, the height the ball reached in flight was given in feet, and putt lengths were given in feet and inches. (I'm not sure whether they were using the International Foot or the Survey Foot.)

Good luck finding a golf course in Australia which has yardage signs on the tees!

 
Now if that golf tournament were in honour of famous grocers, we'd have a real apostrophe war on our hands. [2thumbsup]

Steve
 
Julian, there are other countries which use yards in golf, not just the US. Tradition, you know. I think the UK and Ireland are still in yards, maybe Canada. I must admit to converting from metres to yards myself, though it doesn't make much difference. The sideways measurements are my problems.
 
jhardy1,

Worse - our upstart colony adopts the language of the mother nation it fought to break away from, continues to call that language 'English' instead of 'Americanese' and then corrupts our spellings! 🤣🤣🤣
 
An American quiz show years ago.
"This is a phase spoken by tourists all over the world.
For $1000 name the language."
Five tries, zero dollars.
"Well now for $500 can you tell us the phrase?"
Zero dollars.
"As a consolation prize, what language am I speaking now?"
"American!"
The host visibly cringed as he handed him $50.
There is a slow movement in that direction Scotty.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
A difference of 2 parts per million.

Pffft!

Move along, nothing to see here.

Good Luck,
Latexman
 
@waross ... 'continues to call that language 'English' instead of 'Americanese' and then corrupts fixes our spellings!'
 
"... U.K. [inch] was precisely 25.399977mm, ... On the other hand, the U.S. defined one inch as 25.4000508mm... Johansson actually manufactured inch gauge blocks assuming 1 inch was exactly equivalent to 25.4mm... In later years when the inch definition between the U.S. and U.K. was unified to agree with this definition, Johansson's gauge blocks had penetrated widely in the weapons industry, which then could not help but conform to Johansson's definition. As a result, Johansson might be seen as the originator of the current definition of the inch."

Ref. The History of Gauge Blocks - Mitutoyo America Corporation

 
[quote="... U.K. [inch] was precisely 25.399977mm, ... On the other hand, the U.S. defined one inch as 25.4000508mm... J][/quote]

By international convention, since a few years back, the inch is now defined as precisely 25.4 mm... my understanding...

Dik
 

When dealing with miles... this can amount to a real difference in location.


Dik
 
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