Is there a difference between China 6a and China 6b?

[LaXavier]

There is a difference between China 6a and China 6b. The specific details are as follows: 1. Different standards: China 6a and China 6b have different requirements for the content of carbon monoxide, non-methane hydrocarbons, nitrogen oxides, and PM fine particles in exhaust emissions. Compared to China 6a, China 6b imposes stricter emission requirements for carbon monoxide, non-methane hydrocarbons, nitrogen oxides, and PM fine particles, and the data shows a significant increase in strictness. China 6a can be considered a transitional phase to China 6b. 2. Different implementation times: China 6a was mandatorily enforced for light-duty vehicles starting from July 1, 2020, while China 6b will be mandatorily enforced from July 1, 2023. Below is some relevant information: The China 6 standard, officially known as the 'National Sixth Stage Emission Standard for Motor Vehicles,' includes 'Limits and Measurement Methods for Emissions from Light-Duty Vehicles (China VI)' and 'Limits and Measurement Methods for Emissions from Heavy-Duty Diesel Vehicles (China VI).' The implementation of the China 6 standard will impose stricter requirements on emissions such as carbon monoxide, nitrogen oxides, and hydrocarbons.