When a bus driver sees a hazard that requires slowing down, what should they do to warn drivers behind?

Flashing your brake lights is an effective way to warn drivers behind you when you need to slow down due to a hazard. This action provides immediate and visible feedback to other drivers that you are reducing speed, which is crucial in maintaining safety on the road. By activating the brake lights, you indicate that your vehicle is slowing, allowing following drivers to react in a timely manner and avoid potential rear-end collisions. This is particularly important for larger vehicles like buses, which can take longer to stop.

While hazard lights, the horn, and hand gestures can communicate information to other drivers, they are not as direct or effective as flashing brake lights in this situation. Hazard lights can indicate to other drivers that you are experiencing trouble or are stationary rather than simply slowing down. Using the horn continuously might cause confusion and could be seen as aggressive or alarming. Hand gestures may not be easily seen or understood by drivers behind you, especially in heavy traffic. Therefore, the most reliable method to communicate your intent to slow down in the presence of a hazard is indeed to flash your brake lights.