Office of Traffic, Safety, and Operations Warning Signs Freeway Signing Plan Design April 29, 2008

Office of Traffic, Safety, and Operations 2 Function of Warning Signs –Call attention to unexpected conditions or situations not readily apparent to road users –Alert road users to conditions that might call for a reduction in speed or an action in the interest of safe and efficient operation2C.1

Office of Traffic, Safety, and Operations 3 Placement of Warning Signs –The time needed to complete a reaction to a sign is the sum of time for: Perception Identification (understanding) Emotion (decision-making) Volition (execution) –Table 2C-4 (TEM Chart 6.5) lists suggested sign placement2C.5

Office of Traffic, Safety, and Operations 4 Placement of Warning Signs  MN MUTCD Table 2C-4  TEM Chart 6.5

Office of Traffic, Safety, and Operations 5 Placement of Warning Signs –Distances in Table 2C-4 are for guidance and should be applied with engineering judgment –Signs should not be placed too far in advance of the condition, such that drivers will forget, especially in urban areas2C.5

Office of Traffic, Safety, and Operations 6 Advance Traffic Control Signs –The Stop Ahead and the Yield Ahead signs shall be installed on an approach to a primary traffic control device that is not visible for a sufficient distance to permit the road user to respond to the device.2C.29

Office of Traffic, Safety, and Operations 7 Advance Traffic Control Signs –The Signal Ahead sign shall be installed on an approach to a traffic control signal which does not meet the visibility criteria for a traffic control signal as specified in Table 4D-1.2C.29

Office of Traffic, Safety, and Operations 8 Advance Traffic Control Signs –An Advance Traffic Control sign may be used for additional emphasis of the primary traffic control device, even when the visibility distance to the device is satisfactory.2C.29

Office of Traffic, Safety, and Operations 9 Ramp Meter Ahead Sign –The RAMP METER AHEAD (W3-X1) sign may be used on a freeway entrance ramp having a ramp control signal which is not visible for a sufficient distance to allow a motorist adequate time to bring his vehicle to a stop at the signal.2C.29.1

Office of Traffic, Safety, and Operations 10 Speed Reduction Sign –48” x 48” –Shall be used if the reduction in speed limit between zones is 15 mph or greater For difference in zones of 10 mph or less, use engineering judgment –Shall be installed 1000’ in advance of first speed limit sign May be installed up to 1700’ in advance due to geometrics, grade, or sign clutter –A two-line distance plaque may be used –In-place speed reduction signs shall be replaced through attrition6-6.16

Office of Traffic, Safety, and Operations 11 Advisory Exit Speed Sign / 2C.36 – –Shall be installed if the maximum recommended speed on a ramp, as it exits the mainline roadway, is 70% or less of the design speed of the mainline roadway.

Office of Traffic, Safety, and Operations 12 Advisory Exit Speed Sign 2C.36 – –The Exit Speed sign should be used along the deceleration lane. – –The Exit Speed sign should be visible in time for the road user to make a safe slowing and exiting maneuver. – –The Ramp Speed sign should be visible in time for the road user to reduce to the recommended speed.

Office of Traffic, Safety, and Operations 13 Advisory Exit Speed Sign 2C.36 – –One or more Ramp Speed signs may be used beyond the gore and along the ramp where the recommended speed changes because of a change in curvature or when there is a need to remind road users of the recommended speed. – –Based on engineering judgment, the Ramp Speed sign may be installed on the inside or outside of the curve to enhance its visibility.

Office of Traffic, Safety, and Operations 14 Advisory Exit Speed Sign 2C.36

Office of Traffic, Safety, and Operations 15 Advisory Exit Speed Sign 2C.36 – –A Curve Speed sign may be used at and beyond the beginning of a curve following a Horizontal Alignment and Advisory Speed sign combination. To remind road users of the recommended speed Where the recommended speed changes because of a change in curvature