What is the emission standard for vehicles from 2007?

[MayaDella]

For vehicles from 2007, there are both National II and National III emission standards. 1. The National II standard was implemented nationwide from July 1, 2004. In preparation for the Olympics, Beijing implemented it ahead of schedule. Compared to National I, the National II standard further tightened emission requirements, reducing single-vehicle pollutant emissions by 30% for carbon monoxide and 55% for hydrocarbons and carbon oxides. 2. The National III standard was implemented nationwide from July 1, 2007, primarily applicable to light gasoline and diesel vehicles under 3.5 tons. Vehicles produced before this date adhered to the National II standard. To reduce pollutant emissions, National III vehicles underwent technical upgrades to the engine and exhaust system, including the addition of an onboard diagnostic system and improvements to the three-way catalytic converter. Compared to National II, National III reduces total pollutant emissions by 40%.