What is the difference between China 6a and 6b?
2 Answers
The differences between China 6a and 6b: 1. Different carbon monoxide emissions: The emission standard for carbon monoxide in China 6a is 700 milligrams per kilometer; in China 6b, it is 500 milligrams per kilometer. 2. Different non-methane hydrocarbon emissions: The emission standard for non-methane hydrocarbons in China 6a is 68 milligrams per kilometer; in China 6b, it is 35 milligrams per kilometer. 3. Different nitrogen oxide emissions: The emission standard for nitrogen oxides in China 6a is 60 milligrams per kilometer; in China 6b, it is 35 milligrams per kilometer. China 6 refers to the National Sixth Stage Motor Vehicle Pollutant Emission Standard, which is divided into two phases: 'China 6a' and 'China 6b'.
Last time I changed my car, I specifically studied the difference between China 6a and 6b. Simply put, they are both national sixth-stage emission standards, with China 6b being the upgraded version. The main difference lies in stricter limit values. China 6b has a 30% stricter limit on carbon monoxide emissions compared to China 6a, and hydrocarbon emissions are also reduced by 23%. More importantly, the testing methods differ—China 6b requires real-world driving emissions (RDE) testing (real data from cars on the road), while China 6a mainly relies on laboratory testing. Additionally, China 6b also controls the number of fine particulate matters, which is more beneficial for air quality. Now, China 6b has been fully implemented. If you're buying a new car, I recommend choosing China 6b directly—it has lower long-term maintenance costs and better resale value.
