What does China 6 mean?

[RyderLee]

China 6 refers to the requirement that a vehicle's emission standards meet the specifications of the sixth phase of the national emission standards. The China 6 emission standards were gradually implemented starting from the end of 2019. The national emission standards are categorized as: China 1, China 2, China 3, China 4, China 5, and China 6. The higher the number, the more environmentally friendly the vehicle's exhaust emissions are. The latest national standard introduced is the sixth phase emission standard, which is more stringent, with lower limits on various harmful gases. Vehicle emission standards regulate the levels of harmful gases emitted from vehicle exhaust, such as carbon monoxide, hydrocarbons, and nitrogen oxides. The purpose of setting these standards is to curb the production of these harmful gases, encouraging automobile manufacturers to improve emission standards and reduce the generation of harmful gases.