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INVESTIGATION OF AIR POLLUTANTS DISPERSION AT WORKSTANDS

This paper presents results of research on air pollutants dispersion within a working room. The tests were performed in a woodworking shop room, posing the hazard of exposure to hard wood (oak or beech) dust. The characteristic parameters for evaluation of pollutants dispersion from a machine equipped with a local exhaust ventilation were specified for the room. Three measurement methods (flow visualisation, anemometric, and tracer gases methods) were applied for the tests, enabling determination of air flow directions, air velocity distribution, and variation in concentration of a tracer gas, simulating the real pollution in characteristic points of the working room. The research indicates that air velocity values achieved their maximum within the breathing zone of the employees present at the circular saw and local exhaust ventilation operation area, and amounted from 0.35 m/s up to 0.45 m/s. Moreover, the air flow resulting from the circular saw and the local exhaust ventilation system operation was causing a quicker tracer gas dispersion within the employees’ breathing zone. Tracer gas concentration in the employees’ breathing zone amounted from 1.56 ppm up to 1.81 ppm.