Dive Brief:
- The Environmental Protection Agency on March 27 rescinded a requirement that diesel equipment be equipped with diesel exhaust fluid (DEF) sensors, according to a press release.
- DEF systems, designed to reduce nitrogen oxide emissions, have long been a pain point for the trucking industry. When DEF runs low or sensors fail, vehicles can be forced to sharply decelerate or shut down entirely.
- The EPA’s new guidance encourages manufacturers to adopt monitoring technologies, such as nitrous oxide sensor-based software updates — including retrofits for existing equipment.
Dive Insight:
Diesel vehicles have relied on DEF since 2010 to meet federal emission standards. Over the past 15 years, however, trucking and agriculture businesses have repeatedly reported system malfunctions that make otherwise working equipment inoperable.
EPA Administrator Lee Zeldin described the issue as a “nationwide disaster,” citing widespread failures and their operational impact. The agency said it reviewed preliminary manufacturer data on the faulty systems before deciding to remove the sensor requirement, the release said.
Trucking industry groups welcomed the reversal.
In a statement, the American Trucking Associations VP of Energy and Environmental Affairs Patrick Kelly said defective DEF systems and sensors have frequently taken compliant trucks off the road, triggering costly downtime and broader supply chain disruptions.
“EPA’s decision to provide manufacturers with flexibility to suspend these inducements — and eliminate problematic sensors altogether by monitoring a truck’s actual emissions — is a pragmatic solution that reflects how these systems perform in the real world,” Kelly said.
Todd Spencer, president of the Owner-Operator Independent Drivers Association, echoed that sentiment.
“Small-business truckers have dealt with faulty diesel exhaust fluid systems for years, facing unexpected shutdowns and costly repairs that needlessly take trucks off the road. These are serious operational and safety concerns,” Spencer said in an emailed statement. “We appreciate EPA Administrator Zeldin for listening to the concerns of America’s truckers and issuing commonsense guidance that keeps our supply chain moving.”
