Ermittlung des Durchmessers von Glasfasern für Hochleistungs-Schwebstoffilter - eine vergleichende Untersuchung.

Different methods of determining the fiber diameter and its distribution in high-performance filter media for aerosol filtration equipment are discussed. The direct evaluation of SEM photographs was proved to be the most reliable method. The evaluation algorithm was extended to the case of a correlation between fiber diameter and fiber lenght. Furthermore measurements of the specific surface area to determine the mean fiber diameter were carried out using nitrogen and krypton as adsorptives. For the investigated fibers the fullfilling of the assumptions of the BET-approach was checked. Differences between fiber manufactureres diameter data, based on BET, and the results of the direct diameter evaluation may be expalined by effects of the fiber diameter distribution.