San Diego 2012 ACS Council Report

March 28, 2012

The committee continued to monitor developments in the redefinition of the SI (International System) Base Units. Of particular interest to the committee and the SOCIETY are the redefinitions of the kilogram and the mole. The 24th quadrennial CGPM (General Conference on Weights and Measures) met

in October, 2011. At the meeting, Resolution 1, “On the possible future revision of the International System of Units,” was adopted accepting the proposed “fixed constant” definitions and encouraging further cooperation on their development.

It remains for CODATA (The Committee on Data for Science and Technology) to publish the best, accepted values for the Planck constant (defining the kilogram) and the Avogadro constant (defining the mole). Once available, the fixed values of the constants will be inserted in to the definitions that will be presented for adoption by the next CGPM to be held in 2015.

The committee has continued its reflections upon and consideration of its duties and how they may be more actively pursued.

Peter F. Rusch, Chair