What color is the "hazard" warning light on a tractor-trailer?

The hazard warning light on a tractor-trailer is colored amber or yellow. This color is significant because it is universally recognized as a warning signal, indicating to other drivers that there is a potential hazard or that the vehicle is experiencing some sort of issue or is temporarily stopped. Using amber or yellow helps ensure that the warning is visible from a distance and alerts surrounding traffic to proceed with caution.

Red lights are typically reserved for emergency brake lights, green is used for directional indicators in some contexts, and blue is associated with certain emergency vehicles. Selecting amber or yellow for hazard lights effectively communicates a warning without suggesting an emergency situation, aligning with road safety protocols that prioritize clarity in communication among drivers.