Resolution 6 of the 11th CGPM (1960)
Definition of the metre
The 11th Conférence Générale des Poids et Mesures (CGPM),
- that the international Prototype does not define the metre with an accuracy adequate for the present needs of metrology,
- that it is moreover desirable to adopt a natural and indestructible standard,
- The metre is the length equal to
1 650 763,73wavelengths in vacuum of the radiation corresponding to the transition between the levels 2p10 and 5d5 of the krypton 86atom.
- The definition of the metre in force since 1889, based on the international Prototype of platinum-iridium, is abrogated.
- The international Prototype of the metre sanctioned by the
1st CGPMin 1889 shall be kept at the BIPM under the conditions specified in 1889.
DOI : 10.59161/CGPM1960RES6EFrench text
This definition was abrogated in 1983 by the 17th CGPM (Resolution 1).