A crucial parameter for predictive modeling of the performance of packed columns is the mass transfer rate. An initial screening identified the Onda mass transfer correlation as the most promising predictive model available. The study described here sought to quantify the accuracy that can be expected with the Onda correlation, based on a test data base that was established using 10 literaturereported, pilot-scale investigations and that involved 11 different volatile organic chemicals and 4 basic packing types. The correlation predicted the transfer rate constants within an average standard deviation of 17 percent (437 data points), corresponding to a +30 percent accuracy value for design purposes based on 90 percent confidence limits. Includes 34 references, tables, figures.