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Objective Reliable and transparent assignments of occupational exposure prevalences and levels are crucial for estimating the global burden of disease when occupational exposures contribute to etiology. In this presentation we present an example of using a systematic approach and meta-analysis, done at the initiative of WHO/ILO, to assess global prevalence and levels of exposure to inhaled silica, asbestos and coal dust.Material and Methods A systematic review was conducted of studies of any type, published between 1960 and 2018, if they had been done in working-age populations (≥15 years), provided objective dust or fibre measurements, and directly or indirectly reported an estimate of the prevalence and/or level of occupational exposure to silica, asbestos and/or coal dust. Being exposed was defined as a personal sampling result being above the limit of detection.Results For dust/fibres, 88 studies (>2.4 million measurements, 23 countries, all WHO regions represented) were included, all performed among manual workers. Most studies were performed in construction, manufacturing and mining. Overall, the degrees of evidence for the three exposures varied by the industrial sector between very low and moderate quality of evidence for exposure prevalence, and between very low and low for exposure level. None of the studies included covered the entire workers’ population in each of the industrial sectors.Conclusion Prevalence and level estimates for occupational exposures based on a systematic review approach were probably overestimated in most industrial sectors, thus leading to a need of more representative studies. A way forward for improving exposure estimates in disease burden estimates is to apply different methods, with different assumptions. Still, using the transparent systematic review approach including meta-analysis and quality of evidence evaluation presents an important further step complementing existing approaches for global exposure assessment.