Sponsors (5)
Official title: To amend the Clean Air Act to preserve regulatory stability for motor vehicles, motor vehicle engines, nonroad vehicles, and nonroad engines, and for other purposes.
Introduced July 9, 2026 by Julie Fedorchak · Last progress July 9, 2026
The bill trades a decade of regulatory certainty and reduced near-term compliance risk for vehicle owners, businesses, and manufacturers against delayed emissions tightening that raises near- and long-term health, environmental, and innovation costs and limits local regulatory flexibility.
Vehicle owners, fleet operators, equipment owners, small businesses, and manufacturers get 10 years of regulatory certainty that EPA will not impose standards stricter than the 2007/2010 (Tier 4) levels, reducing near-term compliance costs and uncertainty.
Manufacturers, dealers, purchasers, and fleet operators receive guaranteed multi-year lead times for any successor standards (successor standards must cover at least 3 model years and take effect no earlier than five model years after promulgation), allowing planning and avoiding sudden cost shocks.
Owners, operators, and repair providers are permitted to implement software updates, repairs, diagnostics, and monitoring consistent with specified EPA guidance without triggering penalties, enabling routine maintenance, recalls, and potential cost-saving improvements.
Residents (urban and rural) and the general public face higher pollution exposure and delayed air-quality and climate benefits for up to 10 years because EPA is barred from strengthening vehicle and engine emission standards above 2007/2010 (Tier 4) levels.
Delaying tighter emission controls for a decade slows greenhouse gas reductions and overall progress on air quality, increasing long-term environmental and public-health costs.
State and local governments could be limited in adopting stronger vehicle emission standards or complementary local measures, reducing local policy flexibility to address regional air-quality problems.
Based on analysis of 3 sections of legislative text.
Creates 10-year safe harbors that limit EPA from issuing stricter emission rules for covered diesel on-road and nonroad engines if parties follow specified EPA guidance, and sets lead-time rules for later standards.
Creates temporary 10-year safe harbors that let vehicle and engine makers, fleets, and repairers follow specified EPA guidance on diesel exhaust fluid (DEF) quality, inducement strategies, and certain repair/monitoring practices without triggering prohibitions under the Clean Air Act. During the safe-harbor windows the EPA Administrator is barred from issuing more stringent emission regulations for covered on-road and nonroad diesel engines than the identified legacy standards, with limited exceptions for software updates, anti-defeat enforcement, certain administrative actions, and voluntary manufacturer measures. After each 10-year period, any successor emission standards must meet minimum lead times and model-year application windows and the EPA must consider a set of economic, operational, harmonization, and durability factors before adopting stricter rules. The law preserves existing prohibitions on permanent disablement and does not exempt engines from applicable emission standards or EPA certification and useful-life requirements.