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This exposure assessment was in support of the Artificial Stone worker screening program funded by the Victorian Regulator.The major determinants of RCS exposure were likely to be the proportion of time working on AS, the proportion of time dry processing. For each job, the participants were asked to estimate the proportion of time spent doing dry work and the proportion of time spent near someone else doing dry work for each job and the proportion of work on AS vs natural stone. These parameters were used to derive intensity of exposure to RCS which was used to weight duration of exposure. The ventilation and RPE were not included in the exposure metric.The values used to weight the exposure estimate by intensity of exposure were chosen a priori. We used a 10-fold weighting for dry versus wet work (HSE 2001). Data from four workplaces where granite was being cut showed that changing from dry to wet cutting reduced 8-h TWA exposure by approximately an order of magnitude (Simcox et al., 1999). A similar 10-fold reduction in exposure was seen between wet and dry cutting of AS (Cooper et al., 2015). A weighting factor of 0.3 was used to account for the difference between all natural stone and all AS work. AS typically contains over 90% silica content compared to granite with 30% silica and marble of about 2% silica. The job intensity correlated well with the reported jobs e.g. installer vs machinist vs CNC machine operator. This led to the development of a decision tree grouping workers by specific job types.For individuals, weighted cumulative exposure was calculated by multiplying job exposure intensity values by duration for each job and then adding together the results of all jobs. Averaged exposure intensity was calculated the weighted cumulative exposure by the duration of exposure summed over all reported jobs and this predicted risk of silicosis.