Prediction Model for Particle Fallout in Cleanrooms

Particle fallout in cleanrooms is a primary concern for industries manufacturing super critical products with surfaces highly susceptible to particulate contamination. Limited research has been conducted to predict the contribution of particulate contamination by production activities in cleanrooms. This paper describes a prediction model that utilizes the relationship between airborne particulate contamination and particle fallout, and the relationship between particle fallout and spatial variations, to predict the level of particle fallout on product surfaces in the cleanroom. Experimental modeling and statistical process control techniques were employed in establishing the above relationships and validation was performed by comparing the predictions from the model with actual observations at production cleanrooms.