The aim of the project is to study the dynamics of gas-particle fractionation of aerosols both theoretically and experimentally. Conventional off-line personal samplers are compared to reference direct-reading instruments and evaluated for measurement- and sampling errors. Building on the previous work of project FP0299, experiments will be taken closer to actual workplace aerosols by focusing the work on polar compounds as well as mixtures of two or more substances. An important aspect of the project is the further development of aerosol generation and sampling systems coupled with the integration of mass spectrometric analysis of mixed aerosols.
Our previous study showed that semi-volatile aerosols are highly dynamic and that it is difficult to accurately distinguish particles from vapours. Therefore, development of systems that can separate particles from vapours without sampling artefacts will be further pursued.
Theoretical model calculations and experimental studies on model systems form the basis for understanding and interpretation of the dynamic processes involved.
In the completed project FP 0299 model aerosols (n-alkanes) were therefore studied experimentally and modelled theoretically. In this project it is planned to continue the study with substance mixtures which are closer to the actual aerosols found in workplaces. The investigations will be extended to aerosols from polar compounds and multi-component mixtures. Temperature-controlled chambers will be employed for the study of aerosol dynamics, in order to maintain the temperature as stable as possible. The studies of the dynamics and stability of hazardous semi-volatile aerosols are carried out considering the effect of vapour pressure, temperature, particle size and concentration, and simulate the behaviour of aerosols after their release into the ambient air.
The existing technology that was previously used for the generation of particle populations from pure substances comprised of: condensation aerosol generator, nitrogen dilution, flow-tube reactor, isokinetic sampler and flow splitters will be applied to other groups of semi-volatile substances.
-cross sectoral-Type of hazard:
risk assessment, chemical working substances, measuring methodsDescription, key words:
hazardous semi-volatile multi-component Aerosols, workplace sampling