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Heavy-Duty Inspection and Maintenance Regulation

In January of 2023, CARB instituted a new regulation called the Heavy-Duty Inspection and Maintenance (HD I/M) Regulation. This is a new program to test the emissions systems of nearly all diesel and alternative fuel vehicles over 14,000 lbs. GVW operates in California. This program includes personal vehicles as well.
Fleet/vehicle owners must have a regularly scheduled maintenance program to ensure that their emissions systems remain in proper operating condition. If you have a potential high-emitting vehicle (think “older units”), you could receive a notice from CARB to submit a passing compliance test within 30 days.
If you have vehicles subject to the Periodic Smoke Inspection Program (PSIP), you will continue your annual inspection (smoke opacity or optional On Board Diagnostics (OBD)) and recordkeeping. If you currently use an OBD scan tool, you must ensure that it is one CARB has validated; not all have been.
To perform the HD I/M compliance testing, you must complete CARB’s HD I/M Tester Training Course. This is a free course that is completed online. This course will instruct you on completing the inspections using the various methods available. After you/your employee(s) completes the course, you must pass the online test with an 80%. You would then be issued an inspector's HD I/M Certificate of completion with your Tester Identification Number. This will authorize you to perform the opacity or OBD testing. This tester number will be valid for two years.
Even if you have a valid tester certification from the California Council on Diesel Education and Technology, you must still take the CARB online course and pass the CARB test.
If you use an outside service, it is up to you to confirm that they are CARB-certified testers, or your compliance tests may be deemed invalid.
Resources:
Thank you to our Associate Director, Teresa Dias, Peterson Trucks, for contributing this important information.
For more information, please contact UCON's CARB consultants, Associates Environmental, Inc., at 949-352-4941 and let them know that you are a United Contractors member.