在大气污染中，汽车排出的废气占有很大的部分，尤其是在怠选时排出的coo与co，即碳氢化合物与一氧化碳，浓度更高。因此，我国在1983年就制定了GB3842－83C汽车怠速污染物排放标准》，并列入GB7258－87K机动车运行安全技术条件》的规定中，在各检测站执行至今。其标准值见表1 In the air pollution, the automobile exhaust emissions occupy a large part, especially in the discharge of coo and co, ie, hydrocarbons and carbon monoxide, higher concentrations. Therefore, our country in 1983 formulated the GB3842-83C car idle speed pollutant discharge standard “, and included in the GB7258-87K motor vehicle safety technical conditions” provisions, in the implementation of the test station so far. The standard value in Table 1