Woodworkers’ exposure to airborne particles is measured with different sampling techniques throughout
the world. Due to a great number of exposure data obtained with different samplers, European countries
have aimed over the last ten years to fi nd a conversion factor for mass concentrations that would render
these measurements comparable. Following the accepted EU standards and regulations, we replaced a
25 mm open-faced (OF) fi lter holder with an IOM head to determine woodworkers’ exposure to inhalable
dust and establish an IOM/OF sampler ratio that might serve as a reliable factor for converting the existing
OF data to IOM dust mass concentration in the industrial environment. For this side-by-side sampling we
used personal 25 mm OF (N=29) and IOM (N=29) sampling heads over eight working hours. The obtained
IOM/OF ratios ranged between 0.7 and 2.3. However, mass concentrations obtained by IOM and OF
samplers did not signifi cantly differ. Our fi ndings suggest that there is no need for conversion of the existing
OF data for workers exposed to wood dust, provided that dust mass concentrations in the working
environment range between 1 mg m-3 and 7 mg m-3. Future side-by-side measurements should also involve
environments with low wood dust mass concentrations.