What is the difference between National 4 and National 5 emission standards for vehicles?
3 Answers
The difference between National 4 and National 5 emission standards for vehicles lies in the different upper limits of sulfur content in gasoline: the National 4 standard sets the upper limit of sulfur content at 50mg per kg, while the National 5 standard reduces it to 10mg per kg. Additionally, National 5 introduces standards for particulate matter particle count (PN) and non-methane hydrocarbons (NMHC). National 4 and National 5 refer to different stages of emission standards set by the national government, where higher numbers indicate stricter standards, leading to lower engine emissions. The National 4 emission standard is the fourth stage of motor vehicle pollutant emission standards in China, while the National 5 emission standard is the fifth stage.
National 4 and National 5 mainly differ in emission standards, with significant differences. National 5 requirements are noticeably stricter, greatly reducing pollution emissions. The nitrogen oxide emission limits are 25%-30% lower than National 4, and the particulate matter standards are also more stringent. In terms of timeline, National 4 was implemented around 2010, while National 5 was nationally mandated in 2017. The fuel requirements also differ: National 5 vehicles must use fuel with a sulfur content below 10ppm, which is much cleaner than the 50ppm required for National 4. Technologically, National 5 vehicles are equipped with more advanced OBD systems to monitor emissions and include additional particulate filters. For car owners, National 5 vehicles are now more valuable, can be registered normally in large cities, and many regions have restrictions on National 4 vehicles.
I often study automotive policies, and the main differences between National 4 and National 5 standards are threefold. First, the pollution control levels differ—a National 5 vehicle emits nearly half the total pollutants of a National 4 vehicle over a year. Second, the fuel standards have changed: National 5 requires at least 92-octane low-sulfur gasoline, while National 4 can still use 93-octane. Third, the testing methods have been upgraded—National 5 tests simulate real driving conditions more strictly. There's also a practical impact: be cautious when buying a used National 4 vehicle, as regions like Beijing-Tianjin-Hebei and the Yangtze River Delta restrict transfers, and some cities impose peak-hour traffic restrictions. Long-term, National 5 vehicles can operate for more years, but it's more cost-effective to buy a National 6 vehicle directly now.
