Design parameters and testing techniques for criticality accident detection systems used in various nuclear establishments - a review

Accidental criticality excursion is a potential hazard in operations involving fissile material. In this review paper, design criteria for criticality detection systems, associated requirements for reliable functioning of the instrument and recent advances in the field are discussed. Systems based on integrated dose and rate of change of dose rate concepts are explained. A criticality accident simulator using a pneumatically driven 60Co source for testing the detector is described. The paper also discusses the relative advantages of gamma and neutron sensing devices. (author)