626.4 Transverse Rumble Strips
Transverse rumble strips are placed in the driving lane as a warning device alerting drivers about the need to take action. Transverse rumble strips, having a definite role as a traffic control device to enhance safety, should be considered as enhancements to warning signs such as the Stop Ahead (W3-1) or the various Curve (W1 series) signs.
Placement of transverse rumble strips in the traveled way should be considered when one or more of the following exist and other conventional methods (advance signing, increased sign size, flashers on stop signs, etc.) have been tried.
- When the intersection or roadway condition is hidden from view by either a horizontal or vertical curve, based upon stopping sight distance
- When the intersection or roadway condition has a history of crashes caused by failure to observe a traffic control device
- When the traffic control device follows a long tangent
Rumble strips placed in the traveled way should not be overused. If rumble strips are used at too many locations, they may lose their ability to gain the motorist’s attention. For this reason, transverse rumble strips should only be used at locations where conventional methods are not working.
See Figure 626.4.1, below, for guidance for stop approaches to intersections. Figure 626.4.2 provides additional information for typical dimensions of transverse rumble strips.