When stopped on any road, what must a driver do to warn approaching traffic?

To ensure safety when stopped on any road, activating hazard lights is the most immediate and effective method for warning approaching traffic. Hazard lights make your vehicle more visible to other drivers, signaling that there is a potential hazard or that the vehicle is not moving. This visibility is crucial, especially in low-light conditions or when driving conditions are poor.

Using flares, getting out of the vehicle, or utilizing warning signs are all additional measures that can be effective in certain situations, but they may not always be practical or safe. For instance, placing flares requires the driver to exit the vehicle, which could put them in harm’s way if traffic is nearby. Using warning signs may not be applicable in all situations, particularly in areas without proper signage kits. Therefore, turning on hazard lights serves as a swift, direct means of communicating to others on the road that there is a need for caution.