Fahrzyklus
In 1998, a Swedish researcher criticized the [[New European Driving Cycle]] standard for allowing large emission differences between test and reality. "[[The Washington Post]]" also reported that in the late 1990s, EPA engineers at Virginia Testing Laboratory had built a system called ROVER, designed to test a car's emissions on the road. The project was shut down in 2001, despite preliminary tests indicating gaps between emissions from lab tests and real world tests of about 10 to 20 percent.