ICS 43.040 CCS T 34 GB 中华人民共和国国家标准 GB/T40578—2021 轻型汽车多工况行驶车外噪声测量方法 Measurement methodsfor noise emitted by light-dutyvehicles inmultiple drivingmode conditions (ECE Regulation No.51,Revision 3,2016,Uniform provisions concerning the approval of motor vehicles having at least four wheels with regard to their sound emissions,NEQ) 2021-10-11发布 2022-05-01实施 国家市场监督管理总局 发布 国家标准化管理委员会