In order to make accurate radioactivity measurements of beta-gamma emitters, we need to redefine the manufacturers’ quoted values of the dial settings of the dose calibrators used in a given hospital-based clinical setting. The error (s) in measurements due to the geometry and volumetric variations should also be considered. All these variations could lead to a cumulative error of about 20.0% toward the accuracy in the radioactivity measurements of the beta-gamma emitters. As a part of the quality assurance program, the nuclear medicine centres practicing both low/high dose beta therapies may send the standard radioactivity measurements data to the national suppliers periodically in order to the check the performance or accuracy of their dose calibrators.