We are continuing to follow regulatory developments proposed for the heavy-duty vehicle and engine sector.  In our most recent blog post on the topic, we covered updates on timing for the United States Environmental Protection Agency (US EPA) Cleaner Trucks Initiative and the California Air Resources Board’s (CARB) efforts related to Heavy-Duty Low NOx Omnibus rulemaking and the Advanced Clean Trucks Initiative.  In the past few months, additional progress has been made and both agencies have outlined paths regarding timing.  A summary of such updates and an overview is provided in this post, including a deadline of August 25, 2020 to provide written comments on CARB’s Proposed Heavy-Duty Engine and Vehicle Omnibus Regulation and Associated Amendments.