Euro 7 Draft Lowers NOx Caps


Euro 7 Draft Lowers NOx Caps
A view of smog in Paris, France. © Nightman1965

The European Commission last week released a much-awaited draft of Euro 7, its next automobile emissions standard, focused on cracking down further on nitrous oxides and doubling the length of time that vehicles must comply with limits.

Until now automakers have met nitrous oxide emissions caps chiefly by equipping engines with selective catalytic reduction systems. Adoption of the technology forced engine oil formulators to reduce presence of sulfur, phosphorus and sulfated ash, which were blamed for poisoning SCR systems.

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Members of the European Commission said the proposed emissions standard is intended to reduce air pollution in order to protect the health of Europeans while also avoiding overburdening an auto industry that is working to electrify during a difficult business environment.

“The new rules will help us breathe safer air and help the sector to become greener and more resilient,” commission Executive Vice President Margrethe Vestager said in a Nov. 9 news release. “We need to stick to the objective of the European Green Deal and become a standard setter globally.”

Unlike previous generations, which set twin standards for light- and heavy-duty vehicles, the draft Euro 7 would apply to all vehicles. Successive generations of the standards have always lowered emissions caps, and the main reduction in the draft standard is a 25% reduction in nitrous oxide limits for diesel-powered vehicles, which would bring them in line with those running on gasoline.

Nitrous oxides can exacerbate conditions such as asthma and lung infections and can lead to chronic lung disease.

SCR was one of multiple emissions control systems that required engine oil formulators to limit their use of sulfur, phosphorus and sulfated ash, beginning in the 2000s. Those requirements posed formulary challenges because those chemicals had long been keys to achieving wear prevention and other engine oil performance requirements.

The draft Euro 7 would also double the length of time that vehicles are required to meet emissions regulations – from five years or 100,000 kilometers to 10 years or 200,000 km.

The draft standard would for the first time cap particulate emissions from brakes and tires. Studies have shown brakes to be the largest non-engine sources of particulate matter emissions from transportation.

A public comment period for the draft standard has now begun. After the period concludes, commissions can amend it before presenting a final version to the European Parliament and EU member states for approval.