Design and Set Up of a System for Testing HEPA Filter Efficiency

by Smigielski, Ken Alan

High efficiency particulate air (HEPA) filters by definition have an air particle removal efficiency of ¡Ý 99.97%. Installation of a HEPA filter, however, introduces variables that can compromise the filter¡¯s efficiency. The main objective of this research project was to set up a ¡°filter testing unit¡± to evaluate HEPA filter efficiency in relation to specific filter handling and installation variables. A closed system ¡°HEPA filter testing unit¡± was assembled consisting of a fan, industrial damper, two ducts, and filter housing. The concentrations of a challenge aerosol up-stream and down-stream were used to calculate the filters capture efficiency. Eight filters were evaluated based on filter characteristics, particle capture efficiency, and consistency of proper installation. The results of this study indicated that any damage to the filter or flaw in the handling and installation process can compromise the performance of the HEPA filter significantly.