San Bernardino County, CA Environmental Rules: Vehicle Idling Restrictions (2026)
Key Facts
- Idling Limit
- 5 minutes for off-road equipment
- Applies Since
- Jan. 15, 2009 land use approvals
- Coverage
- Unincorporated county area only
- Enforced By
- County Land Use Services
- Exceptions
- Queuing, safety checks, servicing, warm-up
Summary
San Bernardino County caps off-road diesel equipment idling at five minutes on unincorporated land use project sites, with exceptions for queuing, safety checks, servicing, and reaching operating temperature.
Off-road vehicles/equipment shall not be left idling on site for periods in excess of five minutes. The idling limit does not apply to: (I) Idling when queuing; (II) Idling to verify that the vehicle is in safe operating condition; (III) Idling for testing, servicing, repairing or diagnostic purposes; (IV) Idling necessary to accomplish work for which the vehicle was designed (such as operating a crane); (V) Idling required to bring the machine system to operating temperature; and (VI) Idling necessary to ensure safe operation of the vehicle.
Full Breakdown
The County Code requires off-road diesel vehicles and equipment on discretionary land use development projects approved on or after January 15, 2009, to shut off rather than idle beyond five minutes. The rule targets diesel particulate matter from construction and business equipment operating in the unincorporated area. Operators must also post signs telling drivers to turn off engines when parked, use ultra-low-sulfur diesel fuel, and keep engines maintained. The five-minute cap has built-in exceptions for queuing, safety verification, servicing, designed equipment functions like crane operation, and warm-up to operating temperature.
Violations & Fines
Violations are subject to code enforcement action by County Land Use Services, including citations and correction orders, since this idling limit is one of the Countywide Development Standards in the Development Code.
Frequently Asked Questions
Does the five-minute idling limit apply to my car?
Can equipment idle while warming up or during safety checks?
Is there a different idling limit for a commercial truck parked at a residence?
Sources & Official References
Other rules in San Bernardino County
California rules heatmap·Compare San Bernardino County to another location·View the California environmental rules overview
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