At present,there is neither an officially accepted size-selective fiber sampler,nor are there established performance criteria.In this work,a portotype preclassifier was used to connect a convention alasbestos sampler so that the aerosol penetration test and particle counting proces could be performed.The bias,as a function of particle size,was defined as the difference betweent he measured penetration curve and the target ISO/ACGIH/CEN respirable convention.The imprecision was the standard error with reference to themean aerosol penetration curve. A statistical term,one standard error shift (OSES) was used in a previous study to combine the sampling bias and imprecision.Thebias and imprecision could be for aerosol number,aerosol mass,or even surface area.In this work,an additioal step was taken by introducing another statistical term,maximum sampling shift ,to further combine the OSES with teh counting imprecision.For the surrogate sampler tested,the particle counting imprecision.For the surrogate sampler tested,the particle counting imprecision increased with increasing particle diameter and decreased with increasing geometric standard deviation.The particle counting imprescision was comparable with the OSES,and the resultant MSS map was actually the summation of imprecision and OSES.
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