Abstract View
Investigation of Microscreen System for Fiber Length Classification
BON KI KU, Pramod Kulkarni, Centers for Disease Control and Prevention, NIOSH
Abstract Number: 232
Working Group: Health-Related Aerosols
Abstract
Preparation of length classified fibers is critical for conducting toxicological studies that investigate health effects of fiber aerosols. Recent studies have shown that a fiber separation system using nylon mesh screens can be effective in reducing long tails on the fiber length distributions. However, this approach suffers from poor length resolution. To address this limitation, a high-throughput microscreen system (HMS) has been developed. The HMS induces fiber alignment perpendicular to the flow, through application of external electrical field, followed by separation using etched screens. Aerosolized test fibers in the laboratory were classified using HMS using a series of different nylon mesh screens (5, 10, 20, 30, 41 and 60 µm pore sizes), and the fibers collected on each screen were recovered by washing and their lengths were measured using a phase contrast microscope. The length distribution from each screen with electric field was compared to that from the screen without electric field. The results showed that the mean fiber lengths classified by the HMS without the electric field are 12.4, 11.7, 18.6, 20.9, 25.1 and 50.3 µm for screens corresponding to 5, 10, 20, 30, 41 and 60 µm pore size, respectively. In comparison, the mean length of test fibers was 28.6 µm. Operational characteristics and the data demonstrating the performance of the HMS system will be presented and discussed.