FUNDAMENTAL STUDY ON THE VENTILATION RATE AND VOCS CONCENTRATION IN THE CAR COMPARTMENT

The concentration of CO2 was measured during driving the automobile and during standing. VOCsconcentration was measured during standing. Two ventilation modes were prepared; 1) all fresh airmode and 2) all re-circulation mode in the car compartment. The windows of the automobile werealways closed during this measurement. The ventilation rate and the airchange rate were determinedby the concentration of CO2. Those concentrations were also measured in the classroom withoccupancy and without occupancy for confirming bioeffluents.The concentrations of CO2 during all fresh air mode were stable between 600 and 800ppm. On theother hand, those during all re-circulation mode were dramatically elevated and reached more than3,800ppm. The ventilation rate during driving was similar to that of standing. The ventilation rate duringall re-circulation mode was less than that during all fresh air mode.P-dichlorobenzene was detected in the car compartment only with occupancy. P-dichlorobenzene,which is often used as insecticides, might have been emitted from clothes of person. Several kinds ofVOCs, which might be from human bioeffluents, were detected in the classroom. The influence ofp-dichlorobenzene and these bioeffluents on driving condition should be evaluated.