The standard is formulated as per the Law of the People's Republic of China on the Prevention and Control of Environmental Noise Pollution. It is formulated in reference to the regulation of Uniform Provisions Concerning the Approval of Motor Vehicles Having at Least Four Wheels with Regard to Their Noise Emission (ECE Reg.No.51) of the Economic Commission for Europe of the United Nations (UN/ECE) and based on the actual conditions of motor vehicle products in China. The noise limit for vehicle in the standard is to replace that set down in the standard GB 1495-79. The noise measurement method of the standard is in reference to the Annex 3 of the Uniform Provisions Concerning the Approval of Motor Vehicles Having at Least Four Wheels with Regard to Their Noise Emission (ECE Reg.No.51/02) (1997) of the UN/ECE as well as related content of the international standard of Acoustics - Measurement of Noise Emitted by Accelerating Road Vehicles - Engineering Method (ISO362: 1998) in its technical content. The related requirements on the road surface for noise test of the standard adopt that of the stipulation in the Provisions of the Requirements of Road Surface for the Test of Noise Emitted by Road Vehicles (ISO10844: 1994) and was put into effect as of January 1, 2005. The standard is implemented in two different time periods according to the date of manufacture of the vehicle.