Signal Display and Design Configuration
A traffic signal’s effectiveness depends largely on the ease with which the signal heads can be seen and recognized. For this reason, certain standards have been developed to place signal faces within the motorist's cone of vision, and within a desirable mounting height and location within the intersection.
Signal poles should always be located out of the roadway clear zone. This 'clear' distance varies based on roadway traffic volume and roadway speed. See the BMTE Roadside Safety tutorial for more information, as well as the AASHTO Roadside Design Guide.