This bill would direct the Environmental Protection Agency to change rules so manufacturers of diesel vehicles and nonroad diesel equipment can disable automatic engine derate or shutdown functions when the outside temperature is at or below 0° Celsius. Only the vehicle manufacturer may suspend those functions. The engine must return to normal emissions control operation once temperatures rise above 0° C. The suspension is limited to situations where full engine performance in cold weather is needed to avoid danger, equipment failure, or loss of essential transportation in remote areas.
The bill also would require the EPA to give a year-round exemption from diesel exhaust fluid (DEF) system requirements for covered vehicles that are mainly operated north of 59° north latitude or that face prolonged freezing conditions that make DEF use impractical. That exemption would include not requiring an engine derate or shutdown tied to the absence, malfunction, or fault of DEF systems or their sensors and controllers.
A rule of construction in the bill says emissions standards stay in effect except for the temporary cold-weather mode and the DEF-system exemptions the bill creates.
No publicly available information on federal costs, implementation costs for manufacturers, or economic impacts is included in the bill text or metadata provided.
The bill's findings state that diesel vehicles are vital for critical transportation and emergency services in cold regions; DEF storage, supply, and system function are often unreliable in prolonged freezing conditions; automatic engine shutdowns due to emissions-control malfunctions in extreme cold can pose life-threatening risks; and emissions safeguards were not intended to jeopardize human safety or critical mobility.
No publicly available information on opponents' views, stated objections, or formal analysis of potential environmental or public-health tradeoffs is included in the bill text or metadata provided.