Idle Reduction Requirement at Schools
A school bus driver must turn off the engine upon stopping at a school, or within 100 feet of a school, and may not turn the engine on more than 30 seconds before departing from the location. When the bus is at least 100 feet away from a school, the driver may not idle the engine for more than five consecutive minutes, or for periods totaling more than five minutes during any one hour period. Transit and commercial vehicle operators may not idle for more than five consecutive minutes at each stop within 100 feet of a school, or for periods totaling more than five minutes during any one hour period. 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)