A sign with an orange background and black letters indicates what type of area?

A sign with an orange background and black letters specifically indicates a construction zone. This coloring is designed to alert drivers to areas where there may be road work in progress, which can involve adjustments to traffic flow, additional hazards, and workers in or near the roadway. Bright orange is used for these signs to ensure high visibility, signaling to drivers that they should be particularly cautious and prepared for potential changes in regulations, such as reduced speed limits or detours.

While warning zones do use similar colors, they are generally associated with hazards not specifically related to construction. Closed road signs typically have different colors or designs that indicate the road is not passable, and speed limit areas are marked with white backgrounds and black lettering. Hence, the distinct use of orange for construction zones is a critical aspect in guiding safe driving behavior in those areas.