> In 1959, the relationship of the foot to the meter was officially refined as 1 foot = 0.304 8 meter exactly.<p>We can thank one man for this: Carl Edvard Johansson from Sweden. When making gauge blocks, he decided to round off the inch to exactly 25.4mm, and people around the world used his blocks to manufacture everything. The 1959 change just reflected what industry was already doing.<p>- <a href="http://mitutoyo.com/wp-content/uploads/2013/07/E12016-History-of-The-Gage-Block.pdf#page=8" rel="nofollow">http://mitutoyo.com/wp-content/uploads/2013/07/E12016-Histor...</a><p>- <a href="https://books.google.com/books?id=3rUaAQAAMAAJ&lpg=PA293&ots=hiqJuRiYSM&pg=PA293" rel="nofollow">https://books.google.com/books?id=3rUaAQAAMAAJ&lpg=PA293&ots...</a>
As an example of a problem that can occur: Client wants to survey the elevations of a parcel of land for building a house. The surveyor goes out and collects data with gps survey equipment, which produces a .csv file of northing,easting,and elevation values relative to some National Geodetic Survey benchmark. The engineer imports this .csv into his cad software, produces a grading plan .csv file. The earthmoving contractor imports the grading plan into his software and grades the site.<p>Client gets house built, moves in and discovers that the front yard turns into a swamp after every rain.<p>Somewhere in the chain of importing and exporting .csv files, software A was using survey feet and software B was using international feet.<p>This can also cause problems like structures built in the wrong spot, fences built on neighbors land, etc.
I actually learned of the difference between the U.S. Survey Foot and the International Foot while working on <a href="https://plantpredict.com" rel="nofollow">https://plantpredict.com</a>. For years we had infrequent but bizarre unit-conversion bugs. Calculations literally weren't adding up. We assumed it was related to precision rounding since numeric input fields showed rounded values. It turns out the imperial-to-metric feet conversion factor we picked was 1 of 2 choices, and we picked wrong!
The article left me confused about what it means to have a legally binding redefinition of a term.<p>Does this mean that all existing, legally binding contracts are to be reinterpreted using the new definition of "foot"?<p>Does it mean that any <i>new</i> legal document (contract, legislation, etc.) that uses the term "foot" without further clarification shall be assumed to mean this new definition of "foot"?
A good overview on NSRS can be found below, pretty interesting read if you're into datums.<p><a href="https://www.esri.com/about/newsroom/arcuser/moving-from-static-spatial-reference-systems-in-2022/" rel="nofollow">https://www.esri.com/about/newsroom/arcuser/moving-from-stat...</a>
I knew about the survey foot because both the l00' tape measures I have are in survey feet. Messed me up on a home construction project about 13 years back. It was then I learned there are 2 differing feet definitions.