Study of the Statistical Distribution of Airborne Particles in Class 100, 1000, 10,000 and 25,000 Cleanrooms and Clean Areas.

摘要

Counts were made of the number of particles larger than 0.5 mu m in Class 100, 1000, 10,000, and 25,000 cleanrooms. For each class of room, the frequency distribution of the recorded number of counts is summarized by a graph showing the results of the data collected. The frequency distribution of the actual count data was then compared to the predicted frequency distribution obtain by fitting various statistical models to the data. Three statistical models were used for the frequency distribution of the count data: the normal distribution, the Poisson with zeros distribution, and the negative binomial distribution. Finally, the statistical requirements for the verification of a cleanroom as specified in Federal Standard 209C were applied to one run of count data from each cleanroom or zone. 5 refs., 22 figs., 7 tabs. (ERA citation 14:003305)