This International Standard applies to equipment intended to provide warning of a criticality accident by the detection of gamma radiation, neutrons or both from such an event.
This standard is primarily intended to apply to equipment design and, therefore, does not address the need for placement of such equipment. The need for criticality alarm systems and the utilisation procedures are described in ISO 7753 and ISO 1 1 320.
The primary purpose of the criticality alarm system is to detect radiation from criticality accidents and warn personnel. Suitable alarms shall be provided so that personnel present in the area involved and in adjacent effected areas (often the complete facility) can be warned in the event of a criticality accident occurring. These alarms are intended to activate an evacuation alarm to reduce the probability of serious exposure to personnel.
Such systems may also have secondary functions, such as providing a follow-up measurement of the radiation level during the accident. The systems should only be used for these secondary functions, provided that the secondary functions have no adverse effect on the criticality alarms and their essential characteristics (for example, reliability) described in this standard. The object of this standard is to prescribe general, radiation detection, environmental, mechanical, electromagnetic and documentation requirements and to specify acceptance criteria for criticality accident warning equipment.
This standard is not applicable to photon or neutron dose equivalent (rate) meters or monitors covered by IEC 60532, IEC 60846 (all parts), IEC 61 01 7 (all parts), and IEC 61 005. This standard is not applicable either to equipment or assemblies used in control and safety systems of nuclear reactors.
