European Parliament Environment Committee members have voted against draft proposals to increase diesel car emission limits for nitrogen oxides (NOx) by up to 110%, says Continent-wide automotive supplier body, CLEPA.

The Parliament – based alternately in Brussels and Strasbourg – has the right to veto the proposal – but the Committee insists raising the diesel limit would undermine enforcement of existing EU standards.

The Committee also has reservations concerning the new Real Driving Emissions (RDE) procedure, designed to allow for a more realistic testing of car emissions, by using a portable device and performing the test on the road.

CLEPA notes the European Parliament says in a draft delegated act endorsed by Member States in the Technical Committee for Motor Vehicles (TCMV) on 28 October, the EC proposed, as part of a package of measures setting up the RDE test procedure, to raise the maximum car NOx emission limits by up to 110%.

It justified this by referring to the need to take account of technical uncertainties to do with the use of the new Portable Emission Measurement Systems (PEMS) device.

However, MEPs point out the Commission itself concluded, on the basis of an analysis by the Joint Research Centre (JRC), that the maximum margin of measurement error with this device is 30%, and on average 18.75%.

The committee therefore opposed adoption of the measure.

The issue will be put to a vote by the full Parliament at the 18-21 January plenary session in Strasbourg.