Midblock signals, half signals, and hybrid beacons (also known as HAWKs or hybrid signals) stop traffic fully so that people can walk or bike across. These red indications give people on bikes and other micromobility devices a safe crossing without full signalization of the intersection.
Credit: City of Tucson
Applications
Red indications should be prioritized at locations where cross traffic does not typically yield or where people on bikes must cross multiple lanes at a time. Typical applications are on streets with multiple vehicle lanes on at least one cross-traffic approach, undivided two-lane streets with speeds over 30-35 mph (50-60 km/h), or streets with coordinated or a high density of signals.
Red indications are preferred over RRFBs in locations with more than one lane in each direction.
Actuation
A combination of detection and push-button actuation of the signal or beacon is recommended for maximum utility.
Push button actuation often requires a specific push button for people on bikes to activate the beacon. Buttons should face the bikeway, as should supplemental signs, and should not require a person on a bike to dismount to reach the button. Push buttons for exclusive use by people riding bikes or other shared micromobility devices should not use an Accessible Pedestrian Signal (APS) or locator tone. Any push button used by pedestrians must have a vibrotactile APS button.
Passive detection that automatically changes the signal phase to serve the bikeway can improve people on bikes’ experience. Configure passive detection to minimize rider delay by detecting approaching riders in advance of the intersection1 and beginning the phase change sequence as soon as the bike is detected.
Bikes Wait Here For Signal markings should be installed where loop detectors or other detectors with a specific range are used.
Selecting a Half Signal or a Hybrid Beacon
Half signals and hybrid beacons stop cross traffic so people in the bikeway or crosswalk can proceed. With familiar “green, yellow, red” indications, the half signal has the advantage of universal recognition and comprehension and thus better compliance by drivers. Half signals see about one-third as many motorist violations as hybrid beacons, but both have compliance rates near 100% (99% vs 97%). Half signals that allow minor-street vehicle traffic to proceed across the intersection during the major street’s green phase have been implemented successfully in the U.S. and Canada.2
Half Signals
At half signals, a conventional “green, yellow, red” signal faces the larger of two streets, with a stop sign or flashing red signal facing the smaller street. A pedestrian signal and a bike signal face the smaller street. The signal facing the larger street rests in green, passing into conventional yellow and all-red phases after actuation by a person walking or biking from the minor street. The signal remains solid red throughout the entire green and yellow phases for people on bikes and the Walk and Flashing Don’t Walk phases.
Conventional placement of two signal faces per direction of traffic on the major street is used for half signals. The green signal facing the major street can be louvered to reduce the visible distance, reducing the incentive to speed. The bikeway faces a “green, yellow, red” bike signal. Pedestrians crossing parallel to the bikeway face a pedestrian signal. Motor vehicles approaching from a minor street or a driveway parallel to the bikeway face a STOP (MUTCD R1-1) sign or a flashing red signal.
Both the major street signal and the bike signal use conventional stop-and-go phasing. The bikeway receives a green while cross traffic faces a red signal.
Where the signal is running on recall, it may be advantageous to provide a solid or flashing red signal rather than a STOP (MUTCD R1-1) sign facing the minor street. During the bike green phase, motor vehicles on the minor street face a flashing red signal. At all other times, the motor vehicle signal is red. This option can be implemented without the need for experimentation in the U.S.
Configurations for Half Signals
Right-out intersections. The bikeway allows through and turning movements. Traffic parallel to the bikeway must turn right. Motor vehicle left turns from the major street onto the minor street are sometimes permitted.
Typical intersections. All movements are allowed from both the major and minor streets. Vehicles on the minor approach proceed after stopping. This configuration is more common where the major street has one through lane in each direction.
Hybrid Beacons
Hybrid beacons consist of a signal head with two red lenses over a single yellow lens, typically mounted on a mast arm across a major street. While often used at midblock crossing locations, they were developed for use at major-minor intersections where a full signal is not warranted or where it is undesirable to provide a green indication to the cross street.3
Hybrid beacons use a three-part signal head for motor vehicles, with two red indications over a single yellow indication. When hybrid beacons are used at an intersection instead of midblock, consider using blank-out signs to prohibit conflicting vehicle turns through the bike and pedestrian crossings during beacon operation.
A pedestrian signal is required at a hybrid beacon. Adding bike signals to hybrid beacons more effectively accounts for the different clearance requirements between pedestrians and people on bikes. Bike signals at hybrid beacons are experimental in the U.S.4 If bike signals are not used, the BICYCLES USE PEDESTRIAN SIGNAL (MUTCD R9-5) sign is required. An illuminated sign that reinforces this message may be used, such as a “Bikes Wait/Bikes OK.”
Along major streets, add pedestrian and bike crossing signs and vehicle stop lines to improve driver awareness of the crossing point. A single hybrid beacon with two signal heads facing each direction can control either a pair of directional crossbikes, a pair of crosswalks, a single crosswalk and two-way crossbike, or a single consolidated crosswalk for both bike and pedestrian traffic.
Hybrid beacons are typically installed overhead on mast arms or span wire. They may instead be mounted on pedestrian signal poles on the sides of streets (similar to RRFB placement), typically at a lower cost. Two beacon faces must be installed per approach with at least one overhead. One of the two faces should be installed on a median if a median is present.
Evaluate visibility from both approaches and include supplemental mast arms or signal poles where motor vehicle stop bars may need to be set back farther than 10-30 ft (3-9 m) from the crossing.
In the U.S., the MUTCD provides general guidance on establishing the length of flashing yellow and steady yellow phases. This guidance remains the same regardless of whether the hybrid beacon is used for a pedestrian or bike crossing.
Adjust the hybrid beacon phasing when people on bikes are design users, regardless of whether bike signals are used. Because of the speed at which riders can enter the intersection, hybrid beacons should maintain the solid red indication for motor vehicles throughout the full bike clearance interval.
The minimum length of the major street “rest in dark” interval should be set as short as possible to minimize pedestrian and bikeway user waiting time. Consider using shorter rest-in-dark intervals during off-peak periods than during peak periods.
If bike signals are used at hybrid beacons in the U.S., a request to experiment should be filed. Additionally, to allow people on bikes to treat a hybrid beacon as a “stop then proceed” movement, as it is for motor vehicle drivers, the bike signal head can display a flashing red indication when the hybrid beacon is dark (i.e., the bicycle signal would not rest in dark or on a solid red).
If installed within a signal system, evaluate the need for the hybrid beacon to be coordinated with other signals. Coordination may produce unreasonable delays for people biking and walking on the minor street, leading them to choose what they believe are acceptable gaps before getting the signal and resulting in an empty actuation.
If the hybrid beacon is timed for a two-stage crossing using a median island, consider cascading the call from one direction to the next to reduce the delay between activations.
Hybrid beacons have the potential to conflict with late-arriving users. The MUTCD specifies that the corresponding phase for the pedestrian clearance interval on a major street is alternating flashing red, which allows major street vehicles to stop and proceed if there is no pedestrian. The conflicting movement is a pedestrian countdown display, which in all other signals would be protected from perpendicular travel.
Midblock Signals
Midblock signals may be used where bike and shared-use paths intersect major streets.
Use a pedestrian signal, bike signal, or both for bikeway and pedestrian crossings.
Two types of operation are possible at midblock signals: conventional stop-and-go operation or rest-in-flashing operation. In both cases, the major street signal remains solid red for the duration of the bike green and yellow phase and the Walk and Flashing Don’t Walk phase.
To reduce bike and motor vehicle delay while providing the same benefits as stop-and-go operation, the bike signal can rest on flashing red while the motor vehicle signal rests on flashing yellow. After the signal is actuated, a clearance phase for motor vehicles occurs in which a solid yellow faces motor vehicle drivers while a solid red faces people on bikes. Then people on bikes are given a solid green signal while motor vehicle drivers face a solid red signal. The end of the bike phase is a conventional solid yellow then all-red interval. This operation is similar to emergency vehicle driveway signals.
Signal Warrants
The inability to meet a signal warrant is often cited as a barrier to the implementation of red indications for bikeway crossings. However, practitioners have significant latitude to use engineering judgment to determine whether a signal or other red indication may be needed.5
The U.S. Manual on Uniform Traffic Control Devices (MUTCD) signal and hybrid beacon warrants are not minimum volume requirements for signals. Under MUTCD Section 4C.01, jurisdictions have significant latitude to develop and apply their own warrants or guidelines for signals, beacons, and crosswalks that go beyond minimum requirements.6 Cities can develop, and have developed, supplemental signal warrants for traffic control of bikeways crossing at existing unsignalized locations.
There are also several options provided by the MUTCD to install red indications within the pedestrian volume warrant thresholds:
- In evaluating the pedestrian signal warrant, count all people walking, biking, rolling, and using other non-motorized devices who would likely use the new crossing. Count the number of people crossing the major street at a point closer to the new crossing than to the nearest upstream and downstream signal- or beacon-controlled crossings. Prospective warrants based on a likely increase in walking and biking at the crossing point can also be applied.
- The Coordinated Signal System warrant may be applicable if an engineer judges a hybrid beacon feasible, but the pedestrian signal warrant is not met. The Coordinated Signal System warrant is used where additional signals are needed to improve motor vehicle platooning. Depending on desired speeds, this signal may need to be closer to adjacent signals than the 1,000-foot distance recommended in the MUTCD.
- The Roadway Network warrant is applicable where a bikeway crosses a major street. The bikeway is considered a major route for bike traffic and it is desirable to concentrate bike crossings at this point.
Failure to meet conventional signal warrants should not be the reason preventing cities from making bikeway crossing safer. Conversely, meeting a signal warrant is not necessarily an indication that a bikeway intersection would benefit from a full signal. At intersections where bike and pedestrian traffic meet the signal warrant, a half signal running on recall might still be preferred over full signalization. A full traffic signal can degrade bikeway comfort and effectiveness by increasing waiting times during the red phase and vehicular speeds during the green phase.
While cities need to prioritize the responsible implementation and maintenance of traffic control devices, a failure to meet the quantitative warrant alone is not a reason to avoid implementing signalized crossing for a planned or existing bikeway.
- Alta Planning + Design. Bicycle Detection. Alta, 2021. https://altago.com/wp-content/uploads/Alta-Bike-Detection-White-Paper-July-2021-1.pdf. ↩︎
- Johnson, Todd Robert. “Safety at Half-Signal Intersections in Portland, Oregon.” M.S. diss. Portland State University, 2015. https://pdxscholar.library.pdx.edu/open_access_etds/2200/. ↩︎
- Chapter 4J of the 2023 MUTCD provides guidance and standards for hybrid beacons at unsignalized and mid-block pedestrian crossings, but does not consider hybrid beacons for bicyclist crossings. Where hybrid beacons are installed as pedestrian crossing improvements only, practitioners should follow the MUTCD provisions.
Federal Highway Administration. Manual on Uniform Traffic Control Devices, 11th Edition. USDOT, 2023: Chapter 4J. https://mutcd.fhwa.dot.gov/pdfs/11th_Edition/part4.pdf. ↩︎ - In the U.S., bicycle signals are not supported at hybrid beacons in the MUTCD, 11th Edition. Consider filing an official Request to Experiment with the Federal Highway Administration. ↩︎
- The Urban Bikeway Design Guide or other guidance may be cited in the documentation of engineering judgment decisions. ↩︎
- “The satisfaction of a warrant (or warrants) is one of the relevant factors in the engineering study, but it is not intended to be the only factor or even the overriding consideration. Agencies can install a traffic control signal at a location where no warrants are met, but only after conducting an engineering study that documents the rationale for deciding that the installation of a traffic control signal is the best solution for improving the overall safety and/or operation at the location.”
Federal Highway Administration. Manual on Uniform Traffic Control Devices, 11th Edition. USDOT, 2023: Section 4C.01. https://mutcd.fhwa.dot.gov/pdfs/11th_Edition/part4.pdf. ↩︎