The objective of the present work was to analyse the materials of verification of the newly developed classification of occupational hearing loss harmonized with the international criteria an medico-social expertise of hearing impairment. The classification is designed for the practical application in the clinical work of otorhinolaryngologists, occupational pathologists, and medico-social experts who must practice the identical approaches at all stages of the preliminary and final diagnostics of occupational ear diseases, competence assurance, and social maintenance for the subjects presenting with hearing disorders. The authors emphasize the importance of taking account of presbyacusis characteristics at the stage of pre-nosological changes of the hearing function in the subjects exposed to strong occupational noise, i.e. prior to the appearance of the «signs of noise influence on the organs of hearing". Such an approach makes it possible to eliminate the discrepancies in drawing conclusion about the presence of presbyacusis or "signs of noise influence on the organs of hearing".