[en] Identification of the elements that can be detected in neutron activation analysis (NAA) is discussed descriptively. Classification of the elements detectable in long and short time irradiation were tabulated according to the calculated sensitivities by a FORTRAN program. The activation equation, ko standardization and cadmium ratio were formulated in terms of the sensitivity concept. A FORTRAN computer program was constructed for calculating the specific activity of each characteristic gamma-ray line emitted by a product radioisotope following thermal and epithermal neutron capture in standards of Fe, Co, Zr, Au and W elements. The program also deals with the corrections for the spectrometer dead time, decay times post irradiation and during the measurement. Another FORTRAN program was constructed for calculating the thermal to epithermal neutron flux ratio f as a function of the deviation parameter a of the epithermal neutron spectrum from the ideal 1/E law. In order to determine the reactor parameters f and a for irradiation, the standard samples were placed in a can and irradiated inside the irradiation box 110 at the periphery of the ETRR-2-reactor core at power 16 MW. The values of f and a were found to be 40.23 ± 0.52 and -0.052, respectively. Another FORTRAN program was established to calculate the absolute isotopic thermal neutron intrinsic sensitivity (ITNIS) for all detectable elements in NAA