An Integrated Zonal Model was developed to predict the three-dimensional airflow andcontaminant concentration distributions in a room. This model integrated a zonal model withmaterial emission/sink models. This Integrated Zonal Model was applied to a mechanicallyventilated room to simulate airflow pattern and VOC concentration distributions. Results werecompared with prediction made by a CFD model. It was found that the Integrated ZonalModel could provide sufficiently reliable results and some global information regardingairflow pattern and VOC distributions within a room.