Fibre dusts released at workplaces can put workers' health at risk if they are inhaled in high concentrations and, on the long-term, cause damage to lung tissue due to their biopersistence and shape.
For the implementation and monitoring of occupational exposure limits for fibre dusts, it is necessary to precisely measure their shape down to nanometre range, especially length and diameter.
For such a shape determination, electron microscopes are used. The project aims at increasing their accuracy in measuring nanoscale fibres. For this purpose, software is being developed that uses so-called Monte Carlo methods to simulate those physical scattering processes of electrons on fibres that are relevant for imaging.
The dimensions of a microscopic fibre are to be determined from brightness contrasts of its electron microscopic image. A systematic examination of real and simulated images of fibres of known diameters enables to understand how the unknown diameter of a real fibre can be reliably deduced from its image.
The aim of the project is to provide detailed evaluation instructions and a software tool for precise and reproducible measurement of fibre dimensions using electron microscopy in order to further improve the capabilities for monitoring occupational exposure limits of nanoscale fibres.
The project is being carried out in cooperation with the German National Metrology Institute PTB and relates to the research field of nanometrology. The project is being carried out in cooperation with the German National Metrology Institute PTB and relates to the research field of nanometrology.
Unit 4.5 "Particulate Hazardous Substances, Advanced Materials"
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