| HAWK pedestrian signals
last updated September 7, 2020
years, a new type of pedestrian crossing signal has been implemented
across the US. This signal, officially called a "pedestrian hybrid
beacon", is also known as a "HAWK" signal (High-intensity Activated crossWalK beacon) and is
to provide a protected crossing at a location with heavy
pedestrian activity that does not warrant a full traffic
signal. These are often mid-block locations, but can be located at
regular traffic signals, the HAWK signal has no green indication for
vehicular traffic. Instead, the vehicular signals are dark
until the signal is activated when a pedestrian pushes a button at
the crosswalk. At that point, a unique sequence of signal indications
is activated. Here are those indications and their meanings:
pushbutton has been activated and the signal will turn red soon.
may proceed but should use caution in case the pedestrian begins
is about to change to red. Motorists should
slow and stop if able to do so safely.
vehicles must stop and remain stopped.
must stop, then may
proceed if the
crosswalk is clear of pedestrians.
Studies of the effectiveness of HAWK signals has shown that at
locations where they are installed, vehicle/pedestrian crashes
decreased by 69% and that 96% of motorists comply with the signals.
Conflicting signal meanings and
A significant issue with HAWK signals is that two of the indications
conflict with those of other traffic signals. Most significant is the
use of alternating flashing red lights and its meaning with a HAWK
signal. Alternating flashing red
signals have long been used at both railroad crossings and on
and in those applications have the meaning of "stop and remain stopped"
until the signals stop
flashing. Counterintuitively, at a HAWK signal, the alternating
indicate that a driver must stop but can then proceed if the crosswalk
is clear. A 2016 study
determined that only 27-50% of drivers at the two HAWK signal locations
in the study understood the meaning of the flashing red signal.
a result of
this incongruent meaning, many motorists remain stopped when
the red lights are flashing even if the way is clear. Although this
does not represent a safety issue per se, it increases unnecessary traffic delays,
which the flashing red phase is intended to reduce and was ostensibly
one of the main reasons for development of this signal. It can also
cause aggravation for
drivers behind the stopped driver, some of who may honk or otherwise
express disapproval. And
when knowledgeable drivers do proceed, some drivers may become
frustrated or dismayed at what they believe to be blatant law breaking.
To help ameliorate these potential "road rage" issues, signs such as
the one to the right
are usually posted, but many drivers simply do not notice the
serious is the conflict presented by the dark vehicular indication
when no pedestrians are crossing. Motorists are instructed
to treat dark signals as a stop sign, so having a dark signal
that can be ignored injects more
inconsistency into the traffic system. There is, however, a precedent
for this with ramp metering signals that are dark when not used, and
Texas law exempts drivers from stopping at both dark meter signals and
the opinion of this author, while studies have shown HAWK
signals to be effective in and of themselves, the need for a completely
different signal display for crosswalks is questionable. The existing
red-yellow-green signal can be (and has been in some states) easily
adapted to provide the same operation as a HAWK signal using signals
that drivers are already familiar with.
That aside, the
HAWK signal implementation was not fully baked. Particularly, the meaning of the
alternating flashing red
lights ("wigwag") at a HAWK signal is troublesome as it goes against its
longstanding use with other
traffic control devices such as railroad crossing signals. Having a
than what is used in other applications is counterproductive for having
a system of intuitive and uniform traffic control devices.
Consequently, its use with HAWK signals is
inappropriate and flawed for both practical and conformity
reasons. The Manual on Uniform Traffic Control Devices even
requires that horizontally-aligned flashing red lights at an
intersection be flashed simultaneously "to avoid being confused with
grade crossing flashing-light signals"-- if that justification is valid
for intersection beacons, why not for HAWK signals?
signs such as the one shown above
are often installed to help educate drivers on the contrary meaning of
the flashing red signals in this application. However, posting a
sign to explain a signal meaning that is fundamentally different than
the heretofore standard meaning is a maladroit solution that reaffirms
the HAWK flashing red display is inherently ambiguous. By adopting this
display, both the
National Committee on Uniform Traffic Control
Devices, which evaluates and recommends standards for traffic control
devices in the US, and the Federal Highway Administration, which
ultimately owns those decisions, have failed in their duty to maintain
standardization in the nation's traffic control devices.
The solution is simple: instead
of the alternating flashing red lights, the stop-and-proceed-if-safe phase
should be indicated by simultaneous
red flashing lights such as the one shown to the left. This
would be consistent with other signal indications and more intuitive
better would be to eliminate the HAWK signal entirely and use a
standard red-yellow-green signal with a flashing red signal during the
pedestrian clearance interval. Drivers are already familiar with the
meaning of this signal and it would achieve the desired outcome of reducing unnecessary delays.
regards to the dark signal conflict, a 2016
Federal Highway Administration study did not find that drivers stopped
for dark HAWK signals. That said,
adding more inconsistency does not advance the
idea of a standardized system of traffic laws and devices. Having the
HAWK signal display the flashing yellow at times when not in use by a
pedestrian would provide a more consistent approach and would also have
the benefit of warning drivers of a location where pedestrians might be
crossing without activating the signal. Or, again, just using a regular
red-yellow-green signal that displays a green signal when the crosswalk
is not active would be even better.
these is not like the others / One of these things doesn't belong"
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