CARB Announces Public Workshop on Tier 5 Off-Road Diesel Engine Emission Standards Rulemaking

Share:

10/2/2023

CARBThe California Air Resources Board (CARB) announced a new virtual public workshop regarding its upcoming off-road diesel engine Tier 5 rulemaking activities.

This rulemaking corresponds with CARB’s ongoing work to amend the current Tier 4 off-road diesel engine standards to help California comply with the EPA’s National Ambient Air Quality Standards (NAAQS). CARB staff are proposing drastic reductions of 90% and 75% to both NOx and PM, respectively, when compared to CARB’s Tier 4 emissions standards.  

During this two-day workshop, CARB staff will introduce and discuss various concepts from its latest proposal to reduce criteria pollutants and tailpipe greenhouse gas (GHG) emissions from new diesel engines. Some of these proposals will likely include:

  • Tier 5 implementation timelines
  • Criteria pollutant & GHG emissions standards
  • Off-road Low Load Cycle (LLC) for certification
  • Idling standards
  • Revised warranty and useful life requirements
  • Credit provisions
  • Among other important issues

These proposals are tentatively planned for official Board approval in the 2025 timeframe, with implementation dates starting in 2029 for certain engine families. It is crucial for industry stakeholders to participate in these discussions as much as possible. Through the AEM Engine Emissions Technical Committee (EETC), AEM intends on participating on these workgroup meetings and staying engaged throughout the rulemaking process to better understand CARB’s intentions and to ensure the industry’s voice is represented during these meetings. If you are interested in this topic, or participating on the EETC, please reach out to AEM’s Travis Webb twebb@aem.org or Jason Malcore at jmalcore@aem.org   

The Public Workgroup is scheduled for Oct. 30-31, 2023, from 8 a.m. PST – 5 p.m. PST.  We encourage all stakeholders to register for this workshop and participate on the call.

For more AEM news and updates, subscribe to the AEM Industry Advisor.

AEM Updates, Safety & Product Leadership

For more AEM news and updates, subscribe to the AEM Industry Advisor.

Related Articles

Building the Next Generation of the Workforce: How Stellar Empowers Students Through Hands-On Innovation

Every year, AEM member company Stellar Industries' internship program empowers students to bring their curiosity and ideas to life through hands-on work. Far more than just a...

AEM Testifies in Favor of R&D Before Wisconsin Lawmakers

The AEM Advocacy Team traveled to Madison, Wisconsin this month to testify beforethe Senate Agriculture and Revenue Committee and the Assembly Ways and Means Committee in favor...

As Non-Road Equipment Manufacturers Face Challenges, Hope Builds for 2026 Recovery

For several reasons, 2025hasn’tdeliveredthe growth many were expecting earlierthis year. Global construction activity has fallen short of expectation, and ag equipment sales...

U.S. and Canadian Sales of Agricultural Tractors and Combines Decline in October 2025

According to recent data from AEM, U.S. sales of total agricultural tractors declined 19.6% in October 2025 compared to the year before while combine sales decreased 26.8...

CNH’s Terry Dolan Highlights Sustainability Innovations in Latest Building America’s Promise Video

POLITICO Focus has released the newest installment of its Building America’s Promise series, sponsored by CONEXPO-CON/AGG and AEM. The digital content hub spotlights leaders in...

View all AEM Updates