202 Determinants of asphalt fumes and potential control measures to reduce occupational exposure

Abstract With the current alteration of the bitumen production process, it is not exactly known to which hazardous substances road pavers are exposed to. In an ongoing Dutch exposure survey ~70 exposure measurements are performed to 1.establish these components 2.find exposure determinants 3.evaluate the effect of control measures. Personal and stationary exposure measurements (15 different mixtures) were performed for volatile organic compounds, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, phthalates, formaldehyde, glutaraldehyde, and asphalt fumes. Similar exposure groups identified were asphalt paving operator, engine driver and asphalt labourer. Furthermore, an experimental set-up was designed to evaluate the effect of ventilation system to extract bitumen fumes. The results clarify that the exposure for some of the measured components cannot be classified as compliant according to the criteria mentioned in EN 689. Especially asphalt fumes, formaldehyde and glutaraldehyde were found for both the personal and stationary measurements. The highest exposure levels were found for the asphalt paving operator and the engine driver (20-35% OEL). Mixtures containing a higher percentage of newly added bitumen, high temperature asphalt, polymer modified bitumen and clear bitumen binders result in the highest exposure concentrations (factor 2-3 difference). Applying a ventilation unit to extract bitumen fumes results in a significant decrease at the surface where the asphalt is dispensed, but for personal exposure this reduction in exposure is not observed. More data will be available during the conference to provide data for optimizing technical control measures in order to reduce occupational exposure to carcinogenic asphalt fumes.