What must a bus driver do with access panels, such as baggage, restroom service, or engine panels, before driving?

AAMVA CDL Manual Section 4.1.2, p.4-1

An open access panel can let road debris, exhaust, or water into the bus, and a swinging panel is also a hazard to pedestrians and other vehicles. Making this check a routine last step before pulling away prevents a problem that is easy to create and easy to avoid.