This standard applies to on-line in-core neutron detectors, together with associated
components and instrumentation, designed for purposes important to reactor safety:
protection, information or control. The detector types usually used are direct current ionization
chambers, fission ion chambers and self-powered neutron detectors.
This standard provides guidance for the design of in-core instrumentation for neutron fluence
rate measurements in thermal neutron reactors designed for power production.
The major emphasis in this standard is on the general design aspects of on-line systems.
For the principles of overall system design and for the purpose of neutron flux measurements,
reference should be made to IEC 61513.