This International Standard provides criteria for quality assurance and control, and evaluation of performance of radiobioassay service laboratories. Criteria and guidance for in vivo radiobioassay and in vitro radiobioassay are given in separate clauses. The following are within the scope of this International Standard: - the accuracy of - in vivo measurements of activity and quantities of selected important radionuclides in test phantoms, and - in vitro measurements of activity and quantities of selected important radionuclides in test samples; - minimal requirements for detection limit; - minimum testing levels and testing ranges; - requirements for reporting radiobioassay results by service laboratories; - quality assurance in service laboratories; - quality control in service laboratories; - protocol for reporting test evaluations by service laboratories to the testing laboratory; - default procedures when the service laboratory customer does not specify the performance criteria; - applications of y# for different methods (see Annexes A and B). The following are not within the scope of this International Standard: - detailed radiochemical methods for separating radionuclides from biological samples; - detailed procedures for in vivo and in vitro radioactivity measurements; - biokinetic data and mathematical models for converting radiobioassay results into dose (dose assessment); - procedures for the preparation and distribution of test samples and phantoms by the testing laboratories.