Design & Construction Standards

Traffic and Safety Resources

Rectangular Rapid-Flashing Beacon (RRFB)

An RRFB is an enhanced pedestrian device that uses rapidly flashing yellow lights to warn drivers that a pedestrian is in the crosswalk. The flashing lights are turned on by a push-button that pedestrians can press when they are ready to cross. These enhanced pedestrian devices are typically placed at marked crosswalks where there are no signals or stop signs to control traffic. They may be placed in locations with high pedestrian traffic (like schools and college campuses) or locations where drivers are less likely to yield to pedestrians (like multi-lane roundabouts).

How do they work?

For Pedestrians: Press the button on the signpost and the yellow lights will start flashing. Stay alert and do your best to ensure drivers are yielding before you start to cross.

RRFBs also have features to help those with disabilities, including blind individuals and those with limited vision. The chirping sounds you hear as you approach help people find the button on the signpost. After the button is pressed, you will hear a voice say, “Yellow lights are flashing.” On the curb ramp, the bumps on the yellow panel provide a tactile indication that you are entering the roadway. All these features make crosswalks more accessible to everyone in our communities.

For Drivers: You are required by law to yield to pedestrians in crosswalks, regardless of whether an RRFB is present or whether a pedestrian has activated the flashing lights. The flashing lights are an extra feature intended to draw your attention to the pedestrian in the crosswalk. When you see them flash, slow down or stop to allow the pedestrian to cross. Keep in mind you may be stopping for someone with limited or no vision.

Dowling Roundabouts

In October 2023, we installed RRFBs at the crosswalks at the entrances and exits of the Dowling Road roundabouts in Anchorage. Although other RRFBs exist in the state (on the University of Alaska Fairbanks campus, for example), these are the first of their kind in Anchorage and the first at any roundabout in the state. Because they are a relatively new device, we DOT&PF is currently studying the effectiveness of RRFB devices. are studying how well they work. Specifically, we are looking at whether there is an increase in drivers yielding to pedestrians in the crosswalks at the Dowling roundabouts over time.

Why install them here?

Driver yielding rates to pedestrians in crosswalks at multi-lane roundabouts, and at these roundabouts in particular, tend to be low. This is especially true for crosswalks at roundabout exits. For this reason, the Federal Highway Administration recommends installing RRFBs at pedestrian crossings at multi-lane roundabouts.

We will be measuring driver yielding rates at these crosswalks over the three years after their installation. and comparing them to the yielding rates prior to the installation of the RRFBs. If driver yielding rates at the crosswalks increase over time, we may consider installing these devices at other locations in Anchorage and across the state. Although studies like this have been performed in other states, with yielding rates varying between 19% and 98% at crosswalks with RRFBs, this will be the first study of the new devices in Alaska.

This effort is part of DOT&PF’s commitment to increasing pedestrian safety and accessibility in our communities. We strongly encourage all drivers to do their part by paying special attention at crosswalks and yielding to pedestrians.

Additional resources

• Rectangular Rapid Flashing Beacons (RRFB) – Federal Highway Administration
• Evaluation of Rectangular Rapid-Flashing Beacons (RRFB) at Multilane Roundabouts
• What is an Accessible Pedestrian Signal (APS)?