Investigations on hygiene and sanitary conditions in a laboratory for dental techniques consisted in physico-chemical determinations on microclimate (temperature, humidity, air currents), determination of dust particles (suspended and sedimented), determination of gases (CO, CO2, NO2, NH3, SO4(2-), chloride ions), and determination of microelements (Fe, Cu, Zn, Ni, Cd). In certain conditions the concentrations for dust, NO2, NH3, SO2(4-), chlorine and Cu were above the maximal accepted levels. Measures should be taken for the prevention and for the elimination of these noxious factors by implementing optimal hygienic conditions (heat, humidity, ventilation), by reducing gas emanations, by using protections equipment (mask, eyeglasses, gloves), and by periodic controls of the health status of dental technicians.