What are the differences between China 5 and China 6 emission standards?

[JoyFitz]

The differences between China 5 and China 6 emission standards are as follows: Different emission standards: China 6 emission standards are more than 30% stricter than China 5. Excluding the influence of working conditions and testing, gasoline vehicles' carbon monoxide emissions are reduced by 50%, total hydrocarbons and non-methane hydrocarbons emissions are reduced by 50%, and nitrogen oxide emissions are reduced by 42%. Different implementation times: The China 5 standard was implemented nationwide on January 1, 2017, as the fifth stage of national motor vehicle emission standards. China 6 was implemented starting from July 1, 2019. Different principles: During the China 5 phase, diesel and gasoline vehicles had different emission standards. However, China 6 adopts a fuel-neutral principle, meaning that regardless of the fuel type, the emission limits are the same. Different issuing departments: The China 5 standard was issued by the Ministry of Environmental Protection. The China 6 standard was issued by the Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection, and Quarantine. Different letter representations: China 5 is represented by 'V', while China 6 is represented by 'VI'. Different monitoring requirements for plug-in hybrid electric vehicles: Compared to China 5, China 6 has improved monitoring requirements for plug-in hybrid electric vehicles, including energy storage systems, thermal management systems, brake regeneration, drive motors, generators, and other regulatory aspects. China 5 standard limits are as follows: Gasoline vehicles must not emit more than 1,000 milligrams of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 68 milligrams of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 60 milligrams of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 4.5 milligrams of PM (particulate matter) per kilometer driven. China 6 has two standards: China 6a and China 6b, as follows: China 6a standard limits: Gasoline vehicles must not emit more than 700 milligrams of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 68 milligrams of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 60 milligrams of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 4.5 milligrams of PM per kilometer driven. China 6b standard limits: Gasoline vehicles must not emit more than 500 milligrams of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 35 milligrams of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 35 milligrams of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 3 milligrams of PM per kilometer driven. Affected by the China 6 emission policy, although China 5 vehicles are not currently restricted in normal use, such as driving bans or license plate restrictions, their resale value will be significantly impacted. For truck owners, if they purchase a truck on loan for cargo transport, the vehicle's depreciation after repaying the loan is equivalent to the net profit earned during that period. A higher residual value means more profit for the owner. Therefore, from this perspective, China 6 vehicles, with longer service life and more road rights, have more advantages.

[LaAshlyn]

The core difference between China V and China VI lies in the significantly stricter emission standards. China VI has substantially lowered the emission limits for pollutants such as PM2.5 and nitrogen oxides, helping to alleviate urban smog issues and protect public health. From my daily observations of air quality, I've noticed that China VI vehicles emit only about half the exhaust gases compared to China V, especially under high-temperature conditions. Additionally, China VI introduces real-world driving tests to ensure vehicles reduce air pollution in actual road conditions, making the air we breathe safer. The environmental authorities implemented China VI, and since 2020, most new vehicles have met the standard, promoting green travel and reducing the risk of lung diseases. In short, choosing China VI is not just for a more comfortable drive but also for a cleaner environment for future generations.

[VanBrianna]

From a technical perspective, China VI has optimized engine design and exhaust treatment systems, such as upgrading the three-way catalytic converter, which efficiently transforms harmful gases into harmless substances. During the China V era, vehicles occasionally emitted black smoke, but China VI employs a stricter OBD diagnostic monitoring system to detect emission anomalies in real-time and promptly issue alerts. Based on my maintenance experience, China VI vehicles have more precise components, making part replacements or maintenance slightly more expensive. However, fuel efficiency has improved, saving on fuel costs and reducing consumption losses. Driving a China VI vehicle daily offers quicker acceleration response and a smoother driving experience, without worrying about emission exceedance penalties. Overall, China VI technology drives the automotive industry toward greater reliability.