[Volatile Organic Compounds Emission Characters Based on Business Operations of the Vehicle Repairing Industry in Beijing].

The vehicle repair industry is an important source of volatile organic compound （VOCs） emissions in Beijing. Currently, research on VOCs emissions from the auto repair industry focuses only on organized emissions from spray painting booths and research has not been carried out on the emission characteristics of VOCs in sheet metal, machine repair, and beauty processes. A comprehensive list of VOCs emissions from the entire production process of the auto repair industry lacks. This study selected all 137 auto repair businesses in two districts of Beijing for field investigation. Through activity level research, VOCs content testing of raw and auxiliary materials, and testing of the efficiency of governance facilities, we obtained VOCs emission factors for sheet metal spray painting and machine repair processes （E_Painting=254 g·car^-1, E_Maintain=237 g·car^-1）. Through cluster analysis, we obtained five different types of auto repair businesses and calculated their annual VOCs emissions per store （cluster Ⅰ 0.07 t, cluster Ⅱ 0.36 t, cluster Ⅲ 1.59 t, cluster Ⅳ 0.83 t, and cluster Ⅴ 2.54 t）. The study revealed that sheet metal spray painting remains an important source of VOCs emissions. Given the high number of machine repair vehicles, the total VOCs emissions from the machine repair process cannot be ignored. The 4S stores （cluster Ⅲ to cluster Ⅴ） and franchise stores （cluster Ⅱ） had higher activity levels.