What do National V and National VI mean?

[Linda]

National V emission standard is marked with V, while National VI emission standard is marked with Ⅵ, both using Roman numerals. These refer to China's different stages of motor vehicle emission standards, primarily aimed at controlling and reducing vehicle pollutant emissions. The later the standard, the more energy-efficient and environmentally friendly it is. The differences between National V and National VI vehicles are as follows: 1. Stricter limit requirements for National VI: The National VI standard imposes about 40% to 50% stricter limit requirements compared to National V. In terms of emission standards, National VI reduces nitrogen oxides by 77% and particulate matter by 67% compared to National V. It introduces a limit requirement for particle number (PN) and tightens the durability requirements for emission control devices and the relevant requirements for On-Board Diagnostics (OBD). 2. National VI adopts a fuel-neutral principle: Regardless of the fuel type, the emission limits are the same. In the previous National V stage, diesel and gasoline vehicles had different emission standards. 3. Higher compliance and regulatory requirements for National VI: These include type inspection and information disclosure, production consistency checks, new vehicle inspections, in-use vehicle compliance checks, etc., and simplify the compliance determination method.