Abstract <p>Experimental techniques and methods of experimental data processing for monitoring of controlled neutron fluence with energies greater than 0.1 MeV are described. The approximation of fast neutron fluence values on the basis of experimental values of neutron fluence with energies greater than 1 and 3 MeV, directly measured by Nb- and Fe-monitors, is necessary for the assessment of radiation damage of materials in support of safe operation of nuclear reactors. Reliability of determination of fast neutron fluence values in controlled points of the irradiation device is confirmed by comparative analysis of calculated and experimental data.</p>