I am preparing to buy a motorcycle, and I have been informed that this model meets Euro 4 emission standards. After reviewing information about low emission zones (LEZ) in Hanoi, I understand that vehicles will undergo emission inspections in the future, and those achieving emission level 3 or higher will be permitted to circulate.

Therefore, is there a connection between the vehicle's initial Euro 4 emission standard and emission level 3, and can they be converted or considered equivalent?

I would appreciate any advice to help me feel confident in my purchase and usage. Thank you.