Trescal : Here is the new name of Air Liquide Calibration Service Business

This name carries our symbols :

  • the measurement field (CAL like Calibration and SCAL like Scale),
  • the "TRESCA section" from the French scientist Henri TRESCA who designed the reference prototype of the standard length,
  • the measurement interval by using < (lower than) and > (greater than) to represent the S.

The "Commission of Meter" defined in 1872 a new prototype for the standard length. It was a bar of a modified X cross section shape,

Tresca section

with a length of 102 cm on which two lines were engraved, the distance between the lines defining the standard length. This bar was designed by the French scientist Henri TRESCA (1814-1885). About 30 line standards were used across the world as a primary reference standard for length until 1960.