H.R. 9618 · In committee · Environmental Protection

DEF Act

What it does

Amends the Clean Air Act to establish a 10-year safe harbor for motor vehicle and engine manufacturers that implement inducement strategies or diesel exhaust fluid quality monitoring consistent with specified EPA guidance documents issued in 2025 and 2026.
Prohibits the EPA from promulgating vehicle or engine emission standards more stringent than 2007 or 2010 standards for 10 years from enactment, except for software updates, defeat device enforcement, recall procedures, or voluntary manufacturer actions.
Requires any new EPA emission standards adopted after the 10-year period to apply for at least 3 model years and take effect no earlier than 5 years after promulgation.
Mandates EPA consideration of operational disruption, equipment durability, resale value, owner costs, and national consistency when developing post-10-year emission standards for vehicles and engines.

Jul 14, 2026: Forwarded by Subcommittee to Full Committee by Voice Vote.

Committee: House Environment Subcommittee