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EPA to Propose New Standard on NOx Emissions

The U.S. Environmental Protection Agency will pursue a new rule to address heavy-duty truck and engine emission standards for oxides of nitrogen (NOx) that haven’t been updated in 20 years.

While EPA pointed out that NOx emissions dropped by over 40 percent between 2007 and 2017, it said it plans to publish a proposed rule by early 2020 to address the NOx emissions standard that hasn’t been updated since January 2001. The move is in response to a petition of over 20 organizations that called for new, uniform standards nationwide.

EPA Acting Administrator Andrew Wheeler made the announcement Tuesday, alongside many of these organizations that the Clean Trucks Initiative will further reduce NOx from heavy-duty trucks and engines. The EPA expects those vehicles and engines to account for one-third of all NOx emissions from transportation by 2025.

EPA said it is not required by statute to update the standard, but that further reducing NOx emissions will result in “significant” mobile source reductions while aiding communities nationwide. The agency added that it will also seek to cut “unnecessary red tape,” by simplifying the certification of compliance regulations for heavy-duty trucks and engines.

Deregulation efforts will focus on onboard diagnostic requirements, cost-effective means of reassuring real-world compliance via the use of modern and advanced technologies, the deterioration factor testing process, and concerns about annually rectifying engine families.

The Diesel Technology Forum on Tuesday said the EPA’s announcement sets a vision for heavy-duty diesel engines of the future as “high-value assets.”

“Diesel has always been a technology of continuous improvement and this initiative sets the pace for the next generation of advanced diesel technology,” DTF said in a statement. “Today’s action follows petitions for rulemaking from a number of state and local air agencies, as well as support for a new low NOx standard from truck and engine makers.”

DTF pointed the Advanced Collaborative Emissions Study conducted by the Health Effects Institute that in addition to EPA mandates of ultra-low sulfur diesel, selective catalytic reduction systems for diesel-powered commercial vehicles starting in 2007 have reduced smog-forming NOx emissions by 94 percent. Meanwhile, over that same period, particulate matter filters have reduced particulate matter by more than 90 percent.

Meanwhile, Thomas Built Buses parent company Daimler Trucks North America said Wednesday that it strongly supports the Cleaner Truck Initiative. In a statement, the company said the EPA seeks “to streamline regulatory requirements and improve air quality, while maintaining a regulatory framework that encourages reliable, durable products with low Total Cost of Ownership (TCO).”

“DTNA looks forward to working with the EPA on the Cleaner Truck Initiative,” said Sean Waters, director of regulatory compliance and who attended EPA’s announcement on Tuesday. “We are confident that the Cleaner Air Initiative will provide real-world emission reductions, streamline certification and compliance, and continue to enable us to provide vehicles with the best TCO.”

Daimler Trucks said over the past two decades its vehicles and engines have reduced NOx emissions by over 90 percent and particulate matter by over 98 percent.

Engine and electric drivetrain manufacturer Cummins, Inc. also voiced its support for the EPA initiative. From 1990 to 2010, diesel emissions standards, primarily NOx and particulate matter, were reduced by more than 90 and 98 percent, respectively.

“Cummins has a long history of working with regulators to help develop tough, clear and enforceable standards that lead to a cleaner, healthier and safer environment,” said Jennifer Rumsey, vice president and chief technical officer at Cummins. “We can and should do more to reduce NOx. This is an important step forward because a streamlined, national regulatory program brings consistency across the country allowing manufacturers to develop cleaner, more cost-effective solutions for our customers.”

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