Experimental characterization of particle distribution during the process of reducing the air supply volume in an electronic industry cleanroom

Abstract There is potential for saving energy by reducing the air supply volume during the daily operation of electronic industry cleanrooms . However, there are few studies on the variations in particle distribution characteristics during the reduction of air supply volume. In this study, experiments were carried out in a real cleanroom with non-unidirectional flow to reveal the particle distribution characteristics. Particles were artificially released from two locations. The particle concentrations at 12 positions were measured at fan filter unit (FFU) speeds of 1200 rpm (1597 m 3/h), 1000 rpm (1006 m3/h), 800 rpm (726 m3/h), and 600 rpm (498 m3/h). The results revealed that the particle distribution showed significant non-uniform characteristics under non-unidirectional flow. The characteristics of particle distribution were affected significantly by the air supply volume. There was a large area where the particle concentrations decreased with the decrease in air supply volume. An abrupt increase in particle concentrations occurred at certain locations. The unfavorable positions with high particle concentration could be altered. It was feasible to switch off the FFUs in a subzone that was at a distance from the particle source and to maintain the speed of the FFUs in the source subzone. This was more effective than reducing the air volume as a whole. The total air volume could be reduced by 40.6%. This study could provide guidance for the layout of particle monitoring sensors and reduction of operating air volume in cleanrooms in the electronic industry.