Provides details of a Chinese regulation for measuring pollutants in exhaust from in-use diesel vehicles using remote-sensing equipment. China is the first country in the world to implement such on a national level. The regulation took effect on July 27, 2017 and replaces all local standards related to monitoring diesel vehicle exhaust emissions with remote sensing. It does not mandate remote-sensing programs at the local level, but rather defines a uniform protocol for local agencies to follow if they currently have or decide to implement a remote-sensing program. The goal of the regulation is to eliminate the top 5% of high-emitting vehicles, and it applies to both light-duty and heavy-duty diesel vehicles. The new national regulation defines specific measurement methods for stationary remote-sensing equipment, which is set at fixed locations, and mobile remote-sensing equipment.