What is the National III Emission Standard?

[NevaehFitz]

The National III emission standard mainly refers to: HC emission value below 0.2g/km, CO emission value below 2.3g/km, NOx emission value below 0.15g/km, with no PM requirement. The National III standard is China's third-stage vehicle emission standard. The National III emission standard is equivalent to the European III emission standard, meaning the content of tailpipe pollutants is equivalent to Euro III levels. The difference is that new vehicles must be equipped with an OBD, or On-Board Diagnostics system. The On-Board Diagnostics system features an increased number of detection points and detection systems, with oxygen sensors installed at both the inlet and outlet of the three-way catalytic converter. It ensures compliance by fully monitoring vehicle emissions in real-time, thereby better guaranteeing the enforcement of the Euro III emission standard. When vehicle emissions fail to meet the Euro III standard due to factors like fuel quality, the implementation of the National III standard will increase the cost per vehicle. To stably meet the National III vehicle emission standard, vehicles must be equipped with technical measures that ensure pollutant emissions comply with the National III standard, along with the use of fuel that meets the Euro III standard. Automobile exhaust is the waste gas produced during vehicle use, containing hundreds of different compounds, including pollutants such as solid suspended particles, carbon monoxide, carbon dioxide, hydrocarbons, nitrogen oxides, lead, and sulfur oxides. As the environmental harm caused by vehicle emissions becomes increasingly severe, countries and regions around the world have successively established limits on vehicle exhaust emissions, with the European standard set by the EU serving as a reference standard adopted by most countries and regions. China's National 3 and National 4 standards are based on the Euro 3 and Euro 4 vehicle emission standards.

[DiPhoebe]

As a seasoned driver with years of experience, the China III emission standard, implemented around 2008, is the national third-stage standard primarily targeting exhaust emissions from new vehicles. In terms of limits, for example, gasoline vehicles must not exceed 2.3 grams of carbon monoxide per kilometer, and the combined emissions of hydrocarbons and nitrogen oxides must not exceed 0.50 grams per kilometer. I remember when I first bought my car, this standard led to the phasing out of many older vehicles because engine technologies needed upgrades, such as installing better three-way catalytic converters. Looking back now, the China III standard did improve air quality—like making the smell on the road less pungent, especially reducing smog in big cities. However, the downside is that many cities now restrict China III vehicles. For instance, my old car can't enter urban areas without checking the environmental label or verifying the vehicle's age. Regular maintenance must also ensure emissions tests stay within limits, or annual inspections become difficult. I’d advise friends to upgrade to newer standard-compliant vehicles in time.