Before opening the school bus doors at a stop, what must the driver verify?

PRE-DOOR-OPENING VERIFICATION is the critical moment where driver attention determines whether students will be safe during the loading/unloading process. COMPLETE STOP AND BRAKE: The bus must be completely at rest with the parking brake set — never open doors while still rolling or before the brake is set; TRAFFIC VERIFICATION: Check traffic in BOTH directions; the overhead amber lights and then red lights are the warning system for drivers, but drivers may still not stop; visually confirm approaching traffic has stopped before releasing students; in multiple-lane roads, verify ALL lanes including those beyond the stop bus law's reach; MIRROR SWEEP: Systematically check all mirrors: left flat; left convex; right flat; right convex; cross-view mirrors at the front corners (for students approaching from the sides); HAZARD IDENTIFICATION: Scan for: parked vehicles that may pull out; approaching vehicles that have not stopped; environmental hazards (loose dogs, construction equipment); students who may run out ahead of the authorized exit; ONLY THEN OPEN THE DOOR: Opening the door is the signal to students that it is safe to exit; the door opening must not occur until the above verification is complete; POST-DOOR-OPENING: Continue monitoring mirrors as students exit; the situation can change quickly (a vehicle that was stopped begins moving); do not take eyes off the environment until all students are completely clear.