The process of risk assessment for human health demands the availability of soundly based effects and exposure information. However, many of the available data, particularly those which seek to describe human exposures to chemicals, are of varying quality and scope. Changing public and regulatory expectations increasingly demand that the outcomes of risk assessments are seen to have duly accounted for these data, in order that their conclusions can be viewed as valid. The challenge for risk assessors, therefore, is how the different grades of data should be integrated within the overall process. A series of core values are identified that govern the relationships and the influence that different types of exposure data have within European Union (EU) regulatory risk assessment for chemicals. Building on these values, an approach is presented for evaluating workplace exposure information in the context of how such data might be used within the EU process for assessing the risks to human health of new and existing substances. The implications of adopting the approach for regulatory risk assessment within the EU and its consequent impact on current occupational hygiene practice are discussed.