08 / EMISSIONS & TESTING
Emissions & testing
Identify the specific vehicle and use before opening the official source for testing, fleet, or idling rules. Registration and records for one program do not replace another.
Separate the test required for this vehicle, its compliance deadline and everyday vehicle use. Paying an annual fee or completing one test does not replace checking each vehicle’s requirements.
The testing guidance concerns vehicles subject to Clean Truck Check; idling has a separate scope. CTC concerns covered non-gasoline heavy-duty vehicles operating in California, with specific exemptions. Section 2485 covers on-road diesel commercial vehicles over 10,000 pounds GVWR operating in California and related equipment.
Start with these requirements
OBD and non-OBD vehicles use different testing paths
- What the rule requires
- Identify the OBD testing category from the engine type and Emission Control Label (ECL), rather than the vehicle model year alone. OBD vehicles follow §2196.3 for OBD data testing. Non-OBD vehicles follow §2196.4: diesel vehicles need a smoke opacity test and a visual inspection of emissions-control equipment, while alternative-fuel vehicles need only the visual inspection. Use a credentialed tester and the applicable method, then check CTC-VIS for submission and a passing result. Being tested does not necessarily mean passing.
(b) The owner shall ensure the vehicle is tested via one of the following test
procedures:
(b)(1) OBD-equipped vehicles shall satisfy the periodic testing
requirements through the completion of a passing compliance test
as specified in section 2196.3.
(b)(2) Non-OBD-equipped vehicles shall satisfy the periodic testing
requirements through the completion of a passing compliance test
as specified in section 2196.4.
Use each vehicle’s CTC-VIS deadline
- What the rule requires
- Check this vehicle’s deadline in CTC-VIS. Most covered vehicles currently test every six months. Agricultural vehicles meeting the regulatory definition, and California-registered noncommercial motorhomes for recreational use or emergency occupancy, test annually. Passing results can generally be submitted within the 90 days before the deadline, leaving time for repairs and retesting. Annual fees and testing are separate: payment does not replace testing. After submission, check both a passing result and overall vehicle compliance.
Please always refer to your CTC-VIS account for your due dates.
This is CARB implementation guidance; this statement has no separate regulation subsection.
Read the five-minute rule together with its scope and exceptions
- What the rule requires
- For covered on-road diesel commercial vehicles, both §2485 and alternative §2485.0.1 retain a general five-minute primary-engine idling limit. First read the version-selection conditions preceding §2485. Section 2485(c)(1)(B)1 generally prohibits more than five consecutive minutes; the alternative provision is §2485.0.1(c)(1)(A). Private property is not automatically exempt. A Clean Idle label is not a blanket exemption: the applicable engine standard, label conditions and restricted-area 100-foot boundary matter. Check traffic, queuing and work-related exceptions under paragraph (d) of the applicable version.
- Conditions and exceptions
- The two versions differ in responsible parties, diesel APS conditions and the definition of a restricted area. Section 2485(h)(21) covers property zoned for the specified housing, schools, lodging, hospitals and care facilities with one or more such units on it; §2485.0.1(h)(21) defines it as property zoned for individual or multifamily housing with one or more such units on it. First check the version conditions preceding the main section, then that version’s 100-foot restriction, paragraph (d) exceptions and paragraph (e) requirements under other law. The pre-2008 sleeper-berth exception is not a general present-day exemption.
(c)(1)(B) Except as provided in subsection (d) below, on or after January 1, 2015, any person that owns, operates, or causes to operate any diesel-fueled commercial motor vehicle subject to the requirements of this section shall comply with the following requirements:
(c)(1)(B)1. No vehicle subject to this section shall idle for more than 5 consecutive minutes at any location.
These excerpts come from the retained §2485 library snapshot. Read the two version-selection paragraphs, scope and exceptions in the expanded text, and compare the current CCR link listed in this topic. Open §2485.0.1 separately; do not mix the two versions’ subsection numbers or APS conditions.
WORKED EXAMPLE
Why check the system after getting a test receipt?
Example: a carrier sends a covered vehicle for CTC testing and receives a receipt. The next task is to confirm compliance, not just payment.
Match the vehicle and method
Confirm the test belongs to this vehicle and uses the method for its engine category.
Check submission and outcome
Read the result in CTC-VIS. If it failed or requires retesting, follow the result instructions rather than treating a receipt as proof of a pass.
Check the deadline and compliance status
Complete needed repairs and a passing test by the deadline, then separately check annual fees and unresolved items.
Paid, tested, passed and compliant are different statuses. Do not stop at the first one.
Common mistakes in day-to-day work
CTC, fleet rules and idling are separate
A CTC pass does not establish compliance with every emissions requirement. When changing vehicles, expanding or hauling at ports, check the relevant program’s current applicability and implementation notices through this topic’s regulation index.
Do not assign one testing interval to every vehicle and year
Testing frequency is set out in §2196.1(d) and CARB’s implementation schedule. Under the current schedule, OBD vehicles outside the annual-testing exceptions move to quarterly testing beginning October 2027. Qualifying agricultural vehicles and California-registered noncommercial motorhomes for recreational use or emergency occupancy remain annual. Use this vehicle’s CTC-VIS deadlines; a late test does not automatically move the next deadline.
How to check the idling regulation’s version status
Checked October 17, 2026. OAL still lists permanent-adoption file 2026-0925-04 as pending, and CARB’s Final Approval / OAL Action stage has not yet been reached. A timely certificate of compliance keeps the emergency provisions effective during OAL review, but a submitted PDF does not itself establish that the permanent version is operative. The two paragraphs preceding §2485 separately set version-selection conditions triggered by specified final court rulings. This page does not determine a ruling’s effect on an individual vehicle. Check subsequent CARB notices and the complete applicable text before relying on exceptions, APS or Clean Idle arrangements.
Full text and sources
REGULATION TEXT · ENGLISH
13 CCR § 2196.2 — Periodic Vehicle Emission Testing Requirements
13 CCR § 2196.2 — Periodic Vehicle Emission Testing Requirements
- Source edition date
- Not provided
- Captured
Edition noteOfficial-source snapshot; current consolidated law and subsequent amendments have not been verified.
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REGULATION TEXT · ENGLISH
13 CCR § 2485 Airborne Toxic Control Measure to Limit Diesel-Fueled Commercial Motor Vehicle Idling.
13 CCR § 2485 Airborne Toxic Control Measure to Limit Diesel-Fueled Commercial Motor Vehicle Idling.
- Source edition date
- Not provided
- Captured
Edition noteHistorical text; current applicability has not been verified.
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OFFICIAL GUIDANCE · ENGLISH
Clean Truck Check - Emissions Compliance Testing Requirements
Clean Truck Check - Emissions Compliance Testing Requirements
- Source edition date
- 2026-09-20
- Captured
Edition noteHistorical text; current applicability has not been verified.
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Checked CARB implementation guidance, OAL’s pending list and the official CCR on October 17, 2026. The accessible CCR is current through October 2, 2026 (Register No.40). Fixed library originals and capture dates are retained; the selected §2485 excerpts were compared with the accessible current text. Historical originals are not relabeled as new captures or legal verification records. Permanent-adoption file 2026-0925-04 remains pending; submitted text is not treated as operative permanent law. Check each vehicle’s CTC-VIS deadlines and identify the idling version under the §2485 preface before applying its scope and exceptions. Chinese is CTAC’s plain-language explanation, not an official translation.