Warning signs
A number of warning signs are appropriate for roundabouts and are described below. The amount of warning a motorist needs is related to the intersection setting and the vehicular speeds on approach roadways. The specific placement of warning signs is governed by the applicable sections of the MUTCD.
Circular Intersection sign
A Circular Intersection sign (W2-6) may be installed on each approach in advance of the roundabout. This sign, given in Exhibit 7-6, is proposed as part of the next edition of the MUTCD. When used, it is recommended that this sign be modified to reflect the number and alignment of approaches.
It is also recommended that an advisory speed plate (W13-1) be used with this sign, as shown in Exhibit 7-7. The speed given on the advisory speed plate should be no higher than the design speed of the circulatory roadway, as determined in Chapter 6.
An alternative to the Circular Intersection sign, called a Roundabout Ahead sign, has been proposed and is shown in Exhibit 7-8. At a minimum it is recommended that the Roundabout Ahead sign be used in place of the Circular Intersection sign at mini-roundabouts.
YIELD AHEAD sign
A YIELD AHEAD sign (W3-2 or W3-2a) should be used on all approaches to a roundabout in advance of the yield sign. These signs provide drivers with advance warning that a YIELD sign is approaching. The preferred symbolic form of this sign is shown in Exhibit 7-9.
Large Arrow sign
A Large Arrow sign with a single arrow pointing to the right (W1-6) should be used in the central island opposite the entrances, unless a regulatory ONE-WAY sign has been used. The Large Arrow sign is shown in Exhibit 7-10.
Chevron Plate
The Large Arrow may be supplemented or replaced by a long chevron board (W1-8a, as proposed in the next edition of the MUTCD) to emphasize the direction of travel within the circulatory roadway.
Pedestrian Crossing
Pedestrian Crossing signs (W11-2a) may be used at pedestrian crossings within a roundabout at both entries and exits. Pedestrian Crossing signs should be used at all pedestrian crossings at double-lane entries, double-lane exits, and right-turn bypass lanes. This sign is shown in Exhibit 7-12.
The use of Pedestrian Crossing signs is dependent on the specific laws of the governing state. If the crosswalk at a roundabout is not considered to be part of the intersection and is instead considered a marked midblock crossing, Pedestrian Crossing signs are required. Where installed, Pedestrian Crossing signs should be located in such a way to not obstruct view of the YIELD sign.