What is the difference between National 4 and National 5 vehicle emission standards?
3 Answers
The specific differences between National 4 and National 5 vehicle emission standards are as follows: 1. Different limits on vehicle exhaust emissions: Compared with National 4 standards, the National 5 standards can reduce nitrogen oxide emissions from light-duty vehicles by 25% and from heavy-duty vehicles by 43%. It can be seen that the biggest difference between National 5 and National 4 lies in stricter emission requirements for heavy-duty vehicles. Additionally, the standards for nitrogen oxides (NOX), the sum of hydrocarbons and nitrogen oxides (HCNOX), and particulate matter concentration (PM) have been raised. Furthermore, National 5 has introduced standards for particulate matter particle count (PN) and non-methane hydrocarbons (NMHC). The National 5 standard is comparable to the currently implemented European Stage 5 emission standard in terms of control level. 2. Different information on environmental labels: The emission limits specified on National 4 environmental labels are more lenient than those on National 5 labels.
Recently, I've been researching environmental issues and found that the main difference between China IV and China V vehicle emission standards lies in the stricter regulations. China V is an upgraded version of China IV, resulting in less pollution. China IV standards allow higher emissions of nitrogen oxides and other pollutants, which significantly impact air quality, especially exacerbating smog in urban areas. Under China V standards, emissions of carbon monoxide and hydrocarbons are strictly limited, with each vehicle reducing pollution by about one-third, greatly benefiting environmental improvement. The government's push for China V aims to make vehicles greener, and now many newly manufactured cars meet China V or even China VI standards. Purchasing a China V-compliant car may also qualify for subsidies, helping society reduce pollution in the long run. Personally, I feel more at ease driving such vehicles, breathing cleaner air as a result.
As a mechanic, I can tell you there are significant differences between China IV and China V standards, with numerous technical modifications. The China V vehicles feature upgraded three-way catalytic systems with higher oxidation-reduction efficiency, enabling more effective exhaust gas treatment and being less prone to clogging compared to China IV. The OBD diagnostic system is also smarter, providing early warnings for faults and reducing repair frequency. Maintenance-wise, China V vehicle parts are slightly more expensive, but they have lower failure rates and better long-term durability. I've seen customers drive China V cars for over 100,000 kilometers with minimal exhaust system repairs. Overall, these technological advancements serve environmental protection while making daily driving more worry-free.
