– the intergovernmental organization through which Member States act together
     on matters related to measurement science and measurement standards.
Search facility:

| Site map | News | Contact us
Resolution 2 of the 18th CGPM (1987)
Version française
Study of the surface condition of mass standards

    The 18th Conférence Générale des Poids et Mesures


  • that long-term stability is one of the essential characteristics of mass standards,
  • that improvements in balances now allow variations in mass of only a few micrograms in a kilogram to be observed,
  • that variations of this order have been observed and have been attributed to surface effects due in particular to atmospheric agents,
  • that present methods of cleaning the surfaces of mass standards may have unsuspected effects,
  • that a wide range of methods now exist for the study of the surfaces of alloys used in mass standards,
  • that important results have already been obtained using these methods for the study of the surface contamination of mass standards,
  • recommends that laboratories apply the wide range of techniques now available for the study of surface composition and behaviour to platinum/10% iridium and other alloys used in mass standards.

Comptes Rendus de la 18e CGPM (1987), 1988, p.98
Metrologia, 1988, 25(2), 113-119

The reader should note that the official version of this Resolution is the French text.

Other Resolutions of the 18th CGPM (1987)
Resolution 1
Resolution 2
Resolution 3
Resolution 4
Resolution 5
Resolution 6
Resolution 7
Resolution 8
Resolution 9