Performance requirements are currently being established for instruments used for the particle size-selective sampling of potentially hazardous aerosols in workplaces. In this paper, two methods for the estimation of the sampler performance characteristics bias, imprecision and accuracy are described, for aerosol sampler evaluation data obtained from experiments carried out with monodisperse test aerosols. Application of the methods is illustrated using experimental data for two sampler types, the MRE 113A static respirable sampler and the PM-10 ambient aerosol sampler. Where both methods can be applied to the same data, the estimates obtained using the two methods are in broad agreement. The small number of data points obtained in typical monodisperse-aerosol experiments leads to large uncertainties in the estimated performance characteristics.