EU Science Hub

Transport emissions: JRC to lead development of a new test procedure for cars

Feb 11 2013

In Europe the compliance of emissions from passenger cars with regulatory standards is measured during a predefined test procedure in the laboratory (i.e. the current Euro 5 standard for diesel cars allows for 180 mg NOx emissions per kilometer). Research done by the JRC suggests that this laboratory test does not accurately capture the amount of nitrogen oxides emitted by diesel cars on the road, which is substantially higher.

In view of persisting air quality problems, the European Commission decided in 2010 to address this situation by complementing the current laboratory test with a real-driving test procedure, which should be able to capture the wide range of driving conditions encountered on the road.

A working group led by the JRC and composed by industry stakeholders and Member States representatives was established to assess the potential of 2 candidate procedures: emissions testing with random driving cycles in the laboratory or on road emissions testing with portable emissions measurement systems (PEMS).

A newly published report covers the assessment done, based on emissions testing and expert judgment. On-road emissions testing with a portable device was judged to better cover the wide range of driving and ambient conditions than random laboratory test cycles.

Following the findings of this report, it was decided in December last year to primarily develop on-road testing with PEMS as the main real-driving test procedure. To this end, an extensive vehicle test campaign will be conducted in cooperation with car manufacturers and European technical services in 2013.

The real-driving test procedure may be implemented gradually together with more stringent Euro 6 regulatory standards in 2014, but will only become fully effective from 2017 onwards.