The curie and the roentgen as legal units of measurement.

Abstract

It is a peculiar fact about the genesis and growth of new disciplines that too much rigor too early imposed stifles the imagination and stultifies invention. A certain freedom from the strictures of sustained formality tends to promote the development of a subject in its early stages, even if this means the risk of a certain amount of error. Nonetheless, there comes a time in the development of any field when standards of rigor have to be tightened.SummaryThe need for quantitative expression of the “activity” of radioactive substances and of the dose received from “exposure” to ionizing radiation has led to the development of appropriate units of measurement. The development of the curie and the roentgen as the “recommended” units of measurement of activity and exposure, respectively, and their later adoption in Australia as legal units, prescribed under the Weights and Measures (National Standards) Act 19WM54, are outlined. The present arrangements for the maintenance of official Australian standards of activity and exposure, measured in terms of the curie and the roentgen, respectively, are indicated.