[Physiological and hygienic grounding 8-hour and 12-hour shifts at process production]

On workplaces of an oil refining factory for an estimation of 8-hour and 12-hour shifts the criterion of tiresomeness of work - speed of decrease in working capacity on hours on hours of the working day. Conditions of the industrial environment, physiological intensity of work (density and rate of labour actions), dynamics of parameters of a functional state of an organism of workers, data about symptoms of acute and chronic weariness were analyzed. It is supposed, that at absence of harmful factors of the industrial environment the opportunity of lengthening of a work day till 12-hour is defined by physiological intensity of work - a combination of duration of the working day and week with density and rate of labour actions.