Evaluating a human during occupational activities, occupational physiology should put emphasis on two principal and cooperated directions. Those are aimed to minimize occupational risk, preservation of working capacity, long occupational life and human health. The first direction is associated with theoretic and practical work on differential diagnosis of various functional systems: regulation of working strain, fatigue and tension. Work in this direction helps to solve such practical problems as rehabilitation and assessment of human resources, evaluation of occupational stress, design of automated monitoring systems, etc. The second direction covers hygienic regulation of occupational factors. Their intensity and duration should be assessed with consideration of age, personality and other traits of a worker. In addition, combined action of existing hazards and the new ones should be considered in formation of regulatory technology documents.