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Regulations for Emissions from Vehicles and Engines

Direct Final Rule for Heavy-Duty Highway Program: Revisions for Emergency Vehicles

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Rule Summary

This direct final rule revises the heavy-duty diesel regulations to enable emergency vehicles, such as dedicated ambulances and fire trucks, to perform mission-critical life-saving work without risking that abnormal conditions of the emission control system could lead to decreased engine power, speed or torque. The revisions will allow manufacturers to request and EPA to approve modifications to emission control systems on emergency vehicles so they do not interfere with the vehicles’ missions. 

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