Program Overview

• What is it?
• A new program similar to Smog Check but for heavy-duty vehicles
• Clean Truck Check previously referred to as Heavy-Duty Inspection and Maintenance (HD I/M)

• Who is regulated?
• Diesel and alternative fuel vehicles over 14,000 lbs. GVWR operating in California
• Out-of-state vehicles, public vehicles (federal, state, and local)

• How are they regulated?
• Phase 1 – Started January 2023 with high-emitter screening and testing
• Phase 2 – Starts in mid-2023 with reporting and compliance fee payments
• Phase 3 – Full implementation starts in 2024 with periodic compliance testing

 Opacity Testing