Parking and Transportation

Transportation Resources

Vehicle Idling

Shutting off your engine saves lives. This section tells you about vehicle idling including rules and interesting websites.

  • Idling for one hour burns almost one gallon of gas. (Cosumer Energy Center, CEC, 2010)
  • Ten seconds of idling uses more fuel than restarting your engine. (Consumer Energy Center, CEC, 2010)
  • Electric cars don't idle. (Common Sense, 2010)
  • Idling Fines. Minimum $300; Subsequent penalties can range from $1,000 to $10,000 (American Transportation Research Institute)

Tailpipe emissions are the major source of greenhouse gas emissions and over 50,000 deaths per year. Idling is linked to lung disease, asthma, increased allergies, heart disease and cancer. Because of the known link between idling and health problems, many agencies and organizations are dedicated to reducing these impacts including:

  • U.S. Environmental Protection Agency,
  • California Environmental Protection Agency,
  • California Air Resources Board,
  • California Energy Commission, and
  • local air districts, including the Monterey Bay Unified Air Pollution Control District
  • Many companies also have idling policies to prevent undue health impacts.
  • Laws and Regulations

Heavy-duty truck idle reduction requirements

A driver of a diesel-fueled vehicle with a Gross Vehicle Weight Rating of more than 10,000 pounds is not permitted to idle the vehicle's primary engine for more than five minutes at any location, and is not allowed to operate a diesel-fueled auxiliary power system (APS) on the vehicle for more than five minutes when located within 100 feet of a restricted area. Exceptions do apply in certain situations and for certain vehicles. Any internal combustion APS used in California must comply with applicable state off-road and/or federal non-road emission standards and test procedures for its fuel type and power category to ensure that emissions are not exceeding the emissions of a truck engine operating at idle.

Model Year 2008 and newer heavy-duty diesel engines must be equipped with non-programmable engine shutdown systems that automatically shuts down the engine after five minutes of idling or optionally meets a stringent nitrogen oxide idling emission standard. Operators of trucks equipped with sleeper berths are required to manually shut down the engine when idling more than five minutes at any location within California and are subject to fines for violation. The California Department of Motor Vehicles will not register, renew, or transfer registration for any vehicle operator who has received a violation until the violation is cleared.

(Reference California Code of Regulations Title 13, Section 2485)

Point of Contact

David Chen

Idle Reduction

California Air Resources Board

Phone: (626) 575-6673

Website Link

School bus idle reduction requirement

A driver of a school bus is required to turn off the engine upon stopping at a school, or within 100 feet of a school, and must not turn the engine on more than 30 seconds before beginning to depart from the location. Additionally, the driver may not allow the vehicle to idle at any location greater than 100 feet from a school for more than five consecutive minutes, or for periods totally more than five minutes in any one hour. This requirement also applies to transit and commercial vehicles operating within 100 feet of a school. Exemptions apply for necessary idling while stopped in traffic, at traffic signals, and at the direction of law enforcement personnel. (Reference California Code of Regulations Title 13, Section 2480)

Heavy-duty idle reduction requirement - Sacramento

The City of Sacramento prohibits the idling of all heavy-duty on-road vehicles and all heavy-duty off-road equipment for more than five minutes at a given location. Vehicles, off-road equipment, and transport refrigeration units are also prohibited from extended idling within 100 feet of a residence or school. (Reference Sacramento City Code 8.116)