What are the automotive exhaust emission monitoring standards?
3 Answers
Automobile exhaust emission standards are divided into gasoline vehicle standards and diesel vehicle standards: For gasoline vehicles, the HC emission standards for Euro I, Euro II, Euro III, and Euro IV are 1.1%, 1.1%, 0.66%, and 0.46% respectively; For gasoline vehicles, the CO emission standards for Euro I, Euro II, Euro III, and Euro IV are 4.5%, 4%, 2.1%, and 1.5% respectively; For gasoline vehicles, the NOx emission standards for Euro I, Euro II, Euro III, and Euro IV are 8%, 7%, 5%, and 3.5% respectively; For gasoline vehicles, the PM emission standards for Euro I, Euro II, Euro III, and Euro IV are 0.36%, 0.15%, 0.1%, and 0.02% respectively.
Our testing station conducts exhaust emission tests daily, focusing on four key indicators: Carbon Monoxide (CO) must not exceed the standard, with China VI gasoline vehicles required to emit less than 0.5 grams per kilometer; Hydrocarbons (HC), which significantly pollute the air, are limited to around 0.05 grams. For diesel vehicles, Nitrogen Oxides (NOx) and Particulate Matter (PM) are the main focus, with China VI standards requiring NOx to be less than 0.035 grams. Standards vary for vehicles of different years; for example, China V vehicles have a CO limit of 0.8 grams. During testing, the engine should maintain around 2500 RPM. We recommend that vehicle owners regularly clean the three-way catalytic converter and oxygen sensor, which not only helps pass the annual inspection but also improves fuel efficiency.
Last time a friend asked about this, I did some research and found that the differences between vehicle models are quite significant. For China 6 gasoline vehicles, the focus is on three key metrics: carbon monoxide emissions must not exceed 0.5 grams per kilometer, hydrocarbons must be controlled within 0.05 grams, and nitrogen oxides are capped at 0.035 grams. Diesel vehicles undergo additional testing for particulate matter, with a limit of 0.003 grams. The China 5 standards are more lenient, allowing for 0.1 grams of hydrocarbons, for example. Before the annual inspection, it's advisable to drive at high speeds to burn off carbon deposits, and for older cars, remember to replace the air filter and spark plugs, as these can all affect the readings.
