To avoid propeller strike accidents, make sure ___________ when passengers are boarding or disembarking a boat.

When passengers are boarding or disembarking a boat, turning off the engine is crucial to avoid propeller strike accidents. An active engine poses an immense safety risk, as the propeller can be in motion and create hazardous conditions around the boat. Ensuring the engine is off eliminates this danger and provides a safer environment for passengers to enter or exit the vessel.

While checking the weather, using a ladder, or securing items can be important safety practices in different contexts, they do not directly address the immediate risk associated with a running engine and propeller during boarding and disembarking. Therefore, prioritizing the shutdown of the engine is the most effective measure to enhance safety during these activities.