Tier 3 Vehicle Emission and Fuel Standards (US)

New vehicle emission and lower fuel sulphur standards were agreed March 3rd 2014. These will come into force in 2017.

“Control of Air Pollution from New Motor Vehicles: Tier 3 Emission and Fuel Standards” (or “Tier 3”) are developed by the U.S. Environmental Protection Agency (USEPA) under the US federal Clean Air Act (CAA).

The current USEPA’s Tier 2 Vehicle and Gasoline Sulfur Program, which was finalized in February 2000, took a systems-based approach to motor vehicle pollution by setting standards for both passenger vehicles and their fuel (gasoline). The program set stricter tailpipe and evaporative emissions standards for criteria pollutants from vehicles beginning with model year 2004 and phasing in through 2009. The program also lowered the sulfur content of gasoline to a 30 parts per million (ppm) refinery average, 80 ppm per-gallon cap, and 95 ppm downstream cap; beginning in 2004 and phasing in through 2008. The potential to extend the phase-in for small refiners and approved Gasoline Phase-In Area refiners through the end of 2010 was provided in the Highway Diesel Rule (66 FR 5136, January 18, 2001) in exchange for early compliance with the diesel program.

Similar to the Tier 2 rule, the new rule “Control of Air Pollution from New Motor Vehicles: Tier 3 Emission and Fuel Standards” (Tier 3) is a comprehensive, systems-based approach to address the impact of light-duty vehicles on air quality and health. The Tier 3 rule establishes new standards for light-duty vehicles and new fuel standards for gasoline (including a 10ppm sulphur standard).

Information on the USEPA Tier 3 Emission and Fuel Standards Program is here. (NB: the final rule is not yet published)