When stopping a school bus to load or unload passengers, when should you turn on your upper alternating red signal lights?

Turning on your upper alternating red signal lights before you stop is essential for ensuring the safety of children boarding or disembarking from a school bus. This action serves as a vital warning to other drivers on the road that they should reduce their speed and prepare to stop. By activating the lights before coming to a complete stop, you create a safer environment for passengers, making it clear that they are in a designated loading or unloading zone. This advance warning helps prevent accidents and ensures that motorists are aware of the impending stop well in advance.

Activating the lights once you have stopped, after being stopped for a duration, or just before moving away does not provide the same level of precaution for pedestrians and can lead to dangerous situations. It's critical to follow the law by signaling your intentions ahead of time to protect the safety of all individuals around the bus.