Fibrous inorganic particles with WHO (WHO: World Health Organization) dimensions are measured according to VDI guideline 3492 or, at workplaces, according to DGUV Information 213-546. However, neither method is suitable for determining the concentration of airborne, nanoscale WHO fibers. Both methods only count fibers down to a diameter of 0.2 μm. Therefore, BAuA together with the Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA) and the Swiss Social Accident Insurance (Suva) laid the foundations for a new measurement and evaluation method for nanoscale fibrous materials in the BMBF project nanoGRAVUR. In particular, the need was emphasized to extend the counting range of VDI 3492 and DGUV Information 213-546, which has been limited up to now, at least down to a fiber diameter of 0.02 µm.
The aim of the project was to evaluate the measurement method for its suitability for practical use in terms of sampling, scanning electron microscopic evaluation and fiber morphology assignment and in terms of a statistically reliable determination of workplace concentration.
Within the DGUV-funded project, a validation of the new measurement method was now performed at real workplaces.
Following the analysis of the workplace measurements and adaptation of the measurement and analysis procedure, the first convention can now be revised (together with partner institutes) and the results of the project can be implemented in relevant regulations (DGUV Information 213-546, VDI 3492, CEN TC 137, OECD). At the same time, important information on possible exposures during activities with nanoscale fiber materials was obtained in the project and an assessment of exposures to multi-walled carbon nanotubes (MWCNT), single-walled carbon nanotubes (SWCNT) and other nanoscale fibers became possible for the first time in relation to the German benchmark exposure level of 10,000 F/m3.
-cross sectoral-Type of hazard:
new technologies, measuring methodsDescription, key words:
Exposure, nano, measurement process