THE EVALUATION OF DIAMETER OF GLASS-FIBER S FOR HIGH-PERFORMANCE AEROSOL FILTERS - A COMPARATIVE-STUDY

Different methods of determining the fiber diameter and its distributi on in high-performance filter media for aerosol filtration equipment a re discussed. The direct evaluation of SEM photographs was proved to b e the most reliable method. The evaluation algorithm was extended to t he case of a correlation between fiber diameter and fiber lenght. Furt hermore measurements of the specific surface area to determine the mea n fiber diameter were carried out using nitrogen and krypton as adsorp tives. For the investigated fibers the fullfilling of the assumptions of the BET-approach was checked. Differences between fiber manufacture res diameter data, based on BET, and the results of the direct diamete r evaluation may be explained by effects of the fiber diameter distrib ution.