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Die regellos orientierten Fasern werden mit einem Mikrotom geschnitten und mittels eines Schwingbett-Aerosol-Generators in Luft dispergiert. Es koennen ausser beliebigen Versuchsfasern auch technische Daemmstoffe ("Isolierglasfasern") eingesetzt werden. Das Aerosol wird durch Filterproben auf den Massengehalt an Gesamtstaub kontrolliert. Zur Kontrolle des atembaren Anteils dient der Horizontal-Elutriator, und die Faserzahl wird durch Ausmessen einer Faserprobe im REM bestimmt, die mittels Elektro-Praezipitator niedergeschlagen wurde. Die Aerosole weisen lognormale Verteilung von Faserdurchmesser und Faserlaenge auf.
Studies on fiber aerosols suitable for inhalation are described. The methods used to prepare, generate and characterize glass fiber aerosols are reported. The results of fiber length and diameter determinations were used to classify fibers in a length-diameter matrix. The distribution of fiber volume and aspect ratio (length/diameter) could be determined from this classification. Five fiber preprations were classified and one chosen for inhalation exposure studies. Average fiber length and diameter of this aerosol were 11.4 and 0.16 mym, respectively. Aerosol fiber aspect ratio was lognormally distributed with a median value of 80. The product of aspect ratio and frequency of occurrence was also lognormally distributed with respect to length and diameter. The fiber aerosol contained 4.2-6.1 x 104 fibers/cc of which 6-8% were longer than 20 mym