Concentrations of cadmium in workroom air in a Swedish battery factory were estimated for the time period 1946 to 1976. A sampling strategy was chosen before 389 stationary and 190 mobile measurements took place between December 1974 and February 1976. The studies showed that observations made by the company can be used together with data collected in the present study, the dust in the factory consistE mainly of respirable particles, cyclic variation over time is absent, and type ol work affects the concentration of airborne cadmium dust. Based on these findings earlier measurements in the factory were critically evaluated. It was found that, due to actions taken by the company, the average level of cadmium in workroom air decreased from about 5000 microg Cd/m3 air in 1946 to about 10 microg Cd/m3 air in 1976.