Section 6: Approach SpeedsAnchor: #i1002337
When installing or upgrading a traffic signal, it should be verified that the posted speeds on each of the approaches to the location are still appropriate for current traffic conditions. For details regarding the necessity for 85th percentile speed rechecks, see the Procedures for Establishing Speed Zones manual.
Where approaches are controlled by a STOP sign or traffic signal at the time of the study, the speed check must be conducted far enough away from the location to obtain a speed not affected by the sign or signal. As per Procedures for Establishing Speed Zones, speed check stations should be located midway between signals or 0.2 miles from any signal, whichever is less, to ensure an accurate representation of speed patterns.