The California Air Resources Board will consider the proposed Heavy-Duty Low NOx Omnibus Regulation on 27 August 2020. The proposed regulation is intended to ensure reductions in smog-forming NOx and protect communities most impacted by air pollution.
On-road heavy-duty vehicles are an essential part of the state’s economy. These vehicles are also significant sources of oxides of nitrogen (NOx) and particulate matter (PM), contributing nearly 31% of all statewide NOx emissions as well as 26% of total statewide diesel PM emissions.
The Proposed Heavy-Duty Engine and Vehicle Omnibus Regulation would implement two measures included within California’s Revised 2016 State Strategy for the State Implementation Plan: “Low-NOx Engine Standard” and “Lower In Use Emission Performance Level.”
CARB’s Proposed HD Omnibus Rulemaking would comprehensively overhaul exhaust emission standards and test procedures and other emission-related requirements for 2024 and subsequent model year California-certified HD engines.
Highlights of the regulation include:
Lower NOx and PM emission standards on existing regulatory cycles as well as a new NOx standard on a new low-load certification cycle. The NOx standards would be cut to about 75% below current standards beginning in 2024 and 90% below current standards in 2027.
A revamping of the heavy-duty in-use testing program.
Warranty, Useful Life, and Emissions Warranty Information and Reporting improvements.
Strengthening the heavy-duty durability demonstration program.
Emissions averaging, banking, and trading program improvements.
Powertrain certification test procedures for heavy-duty hybrid vehicles.