When a school bus driver drops off students, they are to turn the bus's engine off.  At pick-up, school bus drivers only turn on their engines when all students are in the vehicle and there is a clear path to exit the pick-up area.

In colder weather, if the warmth of the bus is an issue, idling is to be kept at a minimum and will occur outside the school zone. The "warmed" bus is to enter the school zone as close to pick-up time as possible to maintain warmth, and then shut down.

A bus is allowed to idle in a school zone if the physical layout of the school prevents the bus from "parking" to drop off the students. If this type of environment exists during pick-up, the buses are to arrive and park, even in a queue, and not start until the first bus is loaded.

At school bus depots, limit the idling time during early morning warm-up to what is recommended by the manufacturer (generally three to five minutes). For cold weather, if your vehicle has a plug-in block heater, use that to warm the engine. The block heaters can help avoid starting difficulties and shorten warm-up times.