What factor is important for determining the placement of traffic signs in a work zone?

The placement of traffic signs in a work zone is primarily influenced by visibility from a distance and road speed. This factor is crucial because drivers need sufficient time to react to the signs based on their speed; therefore, signs must be positioned so they can be easily seen and understood from a safe distance.

Effective traffic signage ensures that motorist attention is captured before they enter the work zone, providing crucial guidance and instructions that help maintain safety for both drivers and workers. For instance, if a driver is approaching a work zone at high speed, the signs must be placed far enough in advance to allow for adequate braking time and decision-making.

While the color of the signs is important for indicating meaning, it does not influence placement in the same way visibility and speed do. The cost of materials and the size of the work crew are also not relevant to where signs should be positioned; they focus more on operational aspects of a project rather than on the safety and communication effectiveness that signage placement aims to enhance.