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Nuclear Safeguards Education Portal


A device used to provide information on the flow of nuclear or other material, or on the status of a nuclear facility or equipment. Examples of monitors include:

  • Core discharge monitor (CDM) - A radiation monitoring system that monitors the charging and discharging of irradiated fuel bundles to and from the core of an on-load refuelled power reactor.
  • Spent fuel bundle counter - A radiation monitoring system that counts irradiated fuel bundles as they are discharged to the spent fuel storage bay of an on-load refuelled power reactor.
  • Reactor power monitor - Neutron monitoring system placed outside the reactor biological shield to monitor the power level of the reactor.
  • Radiation passage monitor - A device used to detect, by the radiation emitted, the passage of nuclear material through openings in a containment. For example, dosimeters, such as thermoluminescent dosimeters, can be used as 'yes/no monitors' to confirm the absence of irradiated fuel removals.