Measurement and Analysis of Volatile Organic Compound Emissions from New Vehicle Interiors

Several vehicle-level test procedures exist for measuring and analyzing volatile organic compound (VOC) emissions from new vehicle interiors. In this paper, four vehicle-level procedures were examined to determine the effect of interior air temperature (driver's side breath position), ventilation, vehicle age, and solar load (intensity and source) on the total VOC concentration. A new vehicle (11 days old) was tested over five weeks at interior air temperatures of ambient, 40°C, and 50°C with the ventilation on and off. Three sources of solar load were examined with loads between 600 and 1,100 W/m₂. The three sources of solar load were 5-Zones of halogen lights, an SC03 test site with metal halide lights, and the sun. Total VOCs were measured (μg/m₃) as well as individual hydrocarbons including formaldehyde. Six temperature points in and around the vehicle were monitored over the course of each test. Results indicate that ventilation has the largest effect on the concentration of total VOCs reducing the concentration by a factor of 12-15 with the ventilation on (A/C set to 23°C). There is no difference in the concentration of total VOCs when tested at an interior air temperature of 40°C versus 50°C with the ventilation on. The amount of solar load has more of an effect on the total VOCs than the source of the solar load when comparing the 5-Zone and SC03 test sites. However, the use of the sun as a source of solar load is significantly variable.