Beliefs and practices in the assessment of workplace pollutants

Abstract

SummaryObjectives: A survey was undertaken among Swiss occupational hygienists and other professionals to identify the different exposure assessment methods used, the contextual parameters observed and the uses, diffi culties and possible developments of exposure models for fi eld application. Methods:A questionnaire was mailed to 121 occupational hygienists, all members of the Swiss Occupational Hygiene Society. A shorter questionnaire was also sent to registered occupational physicians and selected safety specialists. Descriptive statistics and multivariate analyses were performed. Results:The response rate for occupational hygienists was 60 %. The so-called expert judgement appeared to be the most widely used method, but its effi ciency and reliability were both judged with very low scores. Long-term sampling was perceived as the most effi cient and reliable method. Various determinants of exposure, such as emission rate and work activity, were often considered important, even though they were not included in the exposure assessment processes. Near fi eld local phenomena determinants were also judged important for operator exposure estimation. Conclusion:Exposure models should be improved to integrate factors which are more easily accessible to practitioners. Descriptors of emission and local phenomena should also be included.Keywords: Occupational hygiene -Exposure assessmentExposure determinants -Exposure models -Expert judgement.Estimating exposure is an important step in occupational health studies, both retrospective, and prospective. Preventive measures and corrective actions against pollutants exposure at the workplace are frequently based on this estimate. It may also play a key role in the recognition of occupational disease. Exposure estimates to chronic pollutants is the traditional fi eld of occupation hygienists and, to a lesser extent, of occupational physicians and occupational safety specialists (e.g. safety engineers). For chemical exposure, direct measurement is certainly the most reliable and objective way to obtain a reliable assessment of the exposure. It must however be stressed that this approach suffers major drawbacks regarding cost and technical complexity. Furthermore, direct measurements only give information on the current exposure (the day of investigation) and do not allow for past exposure estimation, or exposures under other or future conditions (Nicas 2003). Because of these diffi culties, the assessment of occupational exposure relies more and more frequently on different approaches of varying complexity. Table 1 gives a short overview of potential methods considered up to now in occupational hygiene. The most simple and most widely used approach is probably the so-called "expert judgment". Occupational hygienists evaluate whether a potential hazard exists by observing workplace conditions and interviewing the exposed workers about the materials used, the production levels, the duration of exposure, existing preventive measures and so on. Exposure assessment is thus based on...

Evaluating Indoor Exposure Modeling Alternatives for LCA: A Case Study in the Vehicle Repair Industry

“…It would also allow investigators to assess and compare occupational and other indoor and outdoor exposure concentrations (and potential health effects) as applied with various assessment tools, such as LCA. Ranking results obtained with model calculations can be a useful input to comparative assessments, despite the relatively low confidence in the absolute value of exposure estimates [42]. As more field data become available, we expect indoor mass balance models will become important tools in the LCA decision making process.…”