Review and Comparison of NJ Traffic Signal Standards by fyh14669

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									Review and Comparison of NJ Traffic
   Signal Standards and Striping
 Schemes for Pedestrian Crossings

   with Guidance, Standards and
 Recommendations Used Elsewhere
Review of Traffic Signal Standards and Striping Schemes
Accommodating Pedestrians in NJ                                                                                                     3/20/02



Table Of Contest

Introduction............................................................................................................................................2

New Jersey Signal Standards and Striping Scheme Practices.................................................................3

   Overview ............................................................................................................................................3

   Common Practice...............................................................................................................................4

   Enhancements ....................................................................................................................................6
       Brick Crosswalks .............................................................................................................................6
       Exclusive Pedestrian Signal Phasing ................................................................................................8
       Actuated vs. Responsive ..................................................................................................................8
       Walking/ Crossing Speed .................................................................................................................9

   Innovations.........................................................................................................................................9
       Illuminated Crosswalks ....................................................................................................................9
       Pedestrian Signals and Phasing ......................................................................................................10
       Count-Down Signal .......................................................................................................................12
       Moving Eyes..................................................................................................................................13

   Additional Considerations ...............................................................................................................13
       Crosswalks.....................................................................................................................................13
       Traffic Signals ...............................................................................................................................14
       Signal Timing ................................................................................................................................15
       Exclusive Pedestrian Intervals ........................................................................................................15
       Leading Pedestrian Interval ............................................................................................................15
       Other Signal Enhancements ...........................................................................................................16
       Infrared and Microwave Detectors .................................................................................................14

Conclusion............................................................................................................................................17




Pedestrian and Bicycle Resource Project
Rutgers’ Voorhees Transportation Policy Institute                                                                                          1
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Introduction


Rutgers’ Voorhees Transportation Policy Institute (VTPI) has been retained by the New Jersey
Department of Transportation (NJDOT) to establish a Pedestrian and Bicycle Resource Project.
The goal is to provide consistent vision and policy for application throughout the state to
address the needs of pedestrians and bicyclists. To accomplish this TPI is in the process of
establishing an Information Clearinghouse as well as gathering technical resources to make
available for all levels of government throughout New Jersey. As part of the project TPI is also
providing education and training through organization of workshops and conferences, and
assistance in clarifying specific legal and technical issues concerning walking and bicycling.


This discussion paper is presented in two sections:


Section I:          Provides a review of the traffic signal standards and striping schemes used in
                    New Jersey for pedestrian crossings and compares them with guidance,
                    standards and recommendations used elsewhere.
Section II:         Presents findings of enhanced and more innovative practices that could be
                    applied throughout New Jersey.


Guidance and direction for this research was provided by an Advisory Committee consisting of
NJDOT, - county, - local - and consulting engineers. The Committee was appointed at the
beginning of the project to review draft work products, provide assistance and contribute ideas
from their own experience and expertise.




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New Jersey Signal Standards and Striping Scheme Practices


Overview
Pedestrians are accustomed to taking their cues to cross a road from the same traffic lights as
motorists. This practice has not given pedestrian traffic the same benefits as it has vehicular
traffic. In general, signal timing and motor vehicle turning movements delay and sometimes
even prevent people on foot from crossing the street (this is in addition to common motorists
refusal or lack of knowledge to yield the right-of-way to pedestrians as prescribed by law). Even
when pedestrian signals are provided, attempts to reduce motor vehicle delays at signals often
cause increased delays to pedestrians. In areas where both, vehicular and pedestrian volumes
are high, motor vehicle and pedestrian delays should, however, be balanced. To encourage
pedestrians to continue walking rather than choosing to drive and contribute to our already
congested downtowns, travel-time costs to both groups must be incorporated in the
signalization systems.


In addition, all too often, crosswalk striping schemes do
not provide sufficient visibility for both, motorists and
pedestrians and do not generally contribute to the
aesthetics of an area.


Most crosswalks in New Jersey are six feet wide and
consist of 6 inch wide white lines set apart at about 6
feet, which reflects the general standard. This scheme is
considered adequate for roadways of 60 feet or less; no
median or other enhanced safety features are required.


Fortunately, for several years now, in an attempt to               Image: Standard Striped

improve pedestrian safety and enhance our walking               Crosswalk in Bernardsville, NJ.

environment, cities throughout the country are experimenting with adding devices to pedestrian
signals and improving crossing facilities. Some of the signal devices sound tones, chirps or
bells to help visually impaired walkers determine when it’s safe to cross. The new generation of
crossing aids also include high-tech electronic eyes, countdown signals, sensors that detect


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  slower walkers at a crosswalk, and “runaway lights” that flicker and flash to alert drivers when
  someone has entered a crosswalk. Some of these pedestrian-friendly devices are expensive,
  however, the increased safety should justify the costs.


  Common Practice
  The New Jersey Pedestrian Guide recommends that crosswalks should always be at least as
  wide as the sidewalk and never be less than 6 feet in width; 10 feet preferable.




Image: General Crosswalk Striping in New Jersey,            Image: Not very highly visible crosswalk, Maplewood, NJ.
              here: Bernardsville, NJ.



  To add emphasis, NJDOT sometimes uses ladder-striped crosswalks. In fact, ladder striped
  crosswalks are becoming more popular among highway engineers and transportation planners
  since they seem to provide higher visibility for both, motorists and pedestrians. They are also
  more durable, as the gaps in the spacing of the ‘ladder steps’ run parallel to traffic and thus
  allow for a longer lasting of the striping.


  In New Jersey the common practice with traffic signals is to install pedestrian signals at
  intersections where a high volume of foot traffic exists, or, where signals that direct motorists do
  not meet the needs of pedestrians. For example, some intersections occur at odd angles and
  the signals are not visible to the pedestrians. At other locations, turning and merging lanes
  make intersections so complex that special provisions are needed for pedestrians. Where
  existing traffic signals meet the needs of people on foot, the signals are easy to see and provide
  plenty of time to cross the road safely, in these situations special pedestrian signals are
  generally not installed.




  Pedestrian and Bicycle Resource Project
  Rutgers’ Voorhees Transportation Policy Institute                                                     4
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On New Jersey highways, pedestrian traffic signals are generally implemented when the
warrants (numbers of pedestrians and vehicles crossing an intersection) as outlined in the
Manual on Uniform Traffic Control Devices (MUTCD) are met (section 4C.05):


Standard:
The need for a traffic control signal at an intersection or mid-block crossing shall be considered
if an engineering study finds that both of the following criteria are met:


     •    The pedestrian volume crossing the major street at an intersection or mid-block location
          during an average day is 100 or more for each of any 4 hours or 190 or more during any
          hour, and
     •    There are fewer than 60 gaps per hour in the traffic stream of adequate length to allow
          pedestrians to cross during the same period when the pedestrian volume criterion is
          satisfied. Where there is a divided street having a median of sufficient width for
          pedestrians to wait, the requirement applies separately to each direction of vehicular
          traffic.


The pedestrian volume signal warrant is generally not applied when the distance to the nearest
existing traffic control signal along the major street is less than 90m (300 ft), unless the
proposed traffic control signal will not restrict the progressive movement of traffic.


A slightly different warrant is used for school crossings. This warrant calls for a traffic control
signal when the number of adequate gaps in the traffic stream during the period when children
are crossing is less than the number of minutes in the same period and there are a minimum of
20 students during the highest crossing hour.




Image: Graphic Illustration of Pedestrian Signal Heads. Note: The standard was recently changed from the
text signal version “WALK” and “DON’T WALK” to the “Walking Person” and “Upraised Hand” symbols.
                         Newly installed signals are equipped with the new symbol versions.



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If a traffic control signal is justified by both these signal warrants and a traffic engineering study,
the traffic control signal shall be equipped with pedestrian signal heads conforming to
requirements set forth in Chapter 4E of the MUTCD (see below). If a signal is justified by both
conditions outlined above, further guidance applies.


Guidance:
     •    If installed within a signal system, the traffic control signal should be coordinated.
     •    At an intersection, the traffic control signal should be traffic-actuated and should include
          pedestrian detectors. As a minimum, it should have semi-actuated operation, but full-
          actuated operation with detectors on all approaches would also be appropriate.
     •    At non-intersection crossings, the traffic control signal should be pedestrian-actuated;
          parking and other sight obstructions should be prohibited for at least 30m (100ft) in
          advance of and at least 6m (20ft) beyond the crosswalk, and the installation should
          include suitable standard signs and pavement markings.


It is optional to reduce the pedestrian volumes warrant crossing the major roadway as much as
50 percent if the average crossing speed of pedestrians is less than 1.2 m/sec (4ft/sec).
Furthermore a traffic control signal may not be needed if adjacent coordinated traffic control
signals consistently provide gaps of adequate length for pedestrians to cross the street, even if
the rate of gap occurrence is less than one per minute.


Enhancements

Brick Crosswalks
An important component of creating a more pedestrian-friendly environment is to enhance
facilities and to send a clear message to motorists that pedestrians are and could be present.
This can be done for example through implementation of brick paved crosswalks. In fact, the
Pedestrian Guide states that brick pavement of crosswalks can also be beneficial in that they
provide an aesthetically pleasing effect if, however, the following concerns are addressed:


•         They should be laid to a great degree of smoothness;
•         The surface must be slip-resistant when wet; and
•         Long-term maintenance costs should be considered.


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Although the NJDOT has not yet done so on any state highway, various municipalities and
counties have implemented brick paved crosswalks
including the business and/ or downtown districts of Red
Bank, South Orange, Riverton, Maple Shade, Mount
Holly, Morristown (and Moorestown under construction).


Although one of the crosswalks has been in place for
almost ten years now, in most of the locations mentioned
above the installments were made rather recently. The
brick crosswalks are generally outlined with white-
reflective thermoplastic material. Unfortunately in almost
all cases the brick pavement seems to deteriorate rapidly
and has raised safety concerns especially during wet
                                                                           Image: South Orange, NJ.
weather conditions. In addition, if the bricks are not
smooth or even, the surface can add confusion to blind
people using canes or relying on tactile cues for                       Image: South Orange, NJ
wayfinding.


Milwaukee, Wisconsin seems to have come up with a
good solution to the problem. An entire intersection in
downtown was colored and textured to resemble brick
paving stones, except for the crosswalks. The
crosswalks are smooth white concrete, with the
textured surface on either side. The distinctive texture
and color makes the intersection stand out for drivers,
but the pedestrians still have a smooth surface. In
addition each edge of the crosswalk has a border of
                                                                      Image: Smooth crosswalks within
paving stones, providing a tactile guide for blind                         textured intersection.
                                                    i
pedestrians using a cane to navigate .




i
    Perils for Pedestrians, John Z. Wetmore, http://www.pedestrians.org/examples.htm

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Exclusive Pedestrian Signal Phasing
According to NJDOT, exclusive pedestrian signal phases, - all traffic movement restricted while
the pedestrian has the WALK indication – to enhance safety at crossings for pedestrians are
hardly ever implemented on state highways. In one known instance (City of Salem), such signal
timing was implemented after a pedestrian was fatally hit by a tractor-trailer. After it had been
implemented for a couple of years, the State DOT wanted to remove the signal because it
required pedestrians to push a button to activate the signal. Video taping of the situation
indicated that a majority of people attempting to cross, either did so without pushing the button,
or pushed the button and crossed without waiting for the WALK indication. The result was that
often all traffic stopped and no pedestrians would cross. The city of Salem would, however, not
consent to the removal of the exclusive pedestrian signal. In a second known case
(Bernardsville), it was claimed that very long vehicle delays were associated with the activation
of the exclusive pedestrian phase. In addition, the town of Morristown has an exclusive
pedestrian phase signal on state Route 124. The signal is not activated via a push button, but is
allowed to come up with each cycle of the timing. According to local engineers, the signal works
well for pedestrians and only causes minor delays to motor vehicle traffic. According to some
local and state engineers, exclusive pedestrian phasing in general is considered to have an
extremely adverse affect on highway capacities especially during peak hours.

Actuated vs. Responsive
Pedestrian-activated or actuated crossing signals are signals that initiate the crossing phase by
a pedestrian triggering the process by means of a button or other mechanism. Such actuation
tells the signal system that a pedestrian wants to cross, and factors that into the next cycle,
adding to the minimum green time for that move. Generally the response time is not immediate,
in fact, as mentioned above, we often witness that pedestrians cross before they get the cue
because it simply took too long for the signal to change. In contrast, in some of the European
countries where walking and bicycling accounts for a much greater share of all trips made, we
can witness that the majority of pedestrians obey signals. This is to some extent a result of the
way signals are timed (other factors include stronger enforcement and pedestrian safety
education. Especially in busy pedestrian generating areas and school zones with many young
pedestrians, signals are generally pedestrian-responsive rather than just actuated. Pedestrian-
responsive means the light immediately responds (within a matter of seconds) to a pressed
button (or other trigger mechanism). Pedestrian-activated/ actuated signals only make sense
when response time is almost immediate or at minimum very fast (far less than 60 seconds).

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Walking/ Crossing Speed
Another issue besides the response time is the time a pedestrian has and needs to cross a
street. The WALKING PERSON (symbolizing WALK) signal indication is usually displayed for
4-7 seconds, to provide the pedestrian sufficient time to leave the curb/ shoulder. Pedestrian
clearance time (flashing UPRAISED HAND) begins immediately following the WALK indication
and the length of that indication is based upon crossing distance and speed calculations. As
mentioned earlier, the Manual on Uniform Traffic Control Devices suggests 4 feet per second as
a normal walking speed, a speed that as suggested by the Traffic Control Devices Handbook,
(TCDH) perhaps already as many as 30 percent of the current population cannot achieve.
Although the MUTCD states that it is optional to reduce warrants of the pedestrian volumes
crossing the major roadway as much as 50 percent if the average crossing speed of pedestrians
is less than 1.2 m/sec (4ft/sec), it does not make any mention or recommendation to time
signals according to the slower walking speeds. With the proportion of people over the age of
65 increasing, however, we can expect that current signal standards will not ensure safe and
convenient crossing for a majority of our elderly population in the near future. TCDH
emphasizes that, once people enter an intersection, they have the “moral and legal right to
complete the crossing.” ii Today, as a result of various research studies, it is recommended to
use a design walking speed of 2.8 feet/ seconds to accommodate and consider all pedestrians
and longer start-up times of the elderly.iii


Innovations
Some locations in New Jersey have gone beyond the common practice in recognition of the
needs to enhance walking within their communities and/ or counties.

Illuminated Crosswalks
A good example offers Burlington County, which has shown a significant response to pedestrian
and also cyclists needs.



ii
      Richard L. Knoblauch, Martin T. Pietrucha, and Marsha Nitzburg, Field Studies of Pedestrian Walking
Speed and Start-Up Time, Transportation Research Record No. 1538, Transportation Research Board,
1996.
iii
      Staplin, L., Lococo, K., and Byington, S., Older Driver Highway Design Handbook (FHWA-RD-97-135)
Federal Highway Administration, Washington DC, January 1998.

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Burlington County was the first county in the state to install in-pavement lighting at a crosswalk.
It is located on CR 616 in Pemberton Township, between two schools that share facilities.


The device is supposed to alert motorists to the
presence of a pedestrian crossing or preparing to
cross the street. The lights are embedded in the
pavement on both sides of the crosswalk and
oriented to face oncoming traffic. The pedestrian
activates the system (by activating a push-button
but actuation is also possible through passive
detection) and the lights begin to flash, warning
the motorists that pedestrians are in the vicinity of
the crosswalk. Several requests from other
                                                          Image: Graphic illustration of illuminated
municipalities and one hospital have since been           crosswalk. Source: www.walkinginfo.org
made to ask permission to install lighted
crosswalks as well. In fact, in Denville NJDOT recently installed a pavement mounted
strobelight system on a jughandle to Route 46 on Savage Road. The yellow strobes in the
pavement start flashing automatically when a pedestrian is near or enters the crosswalk. The
system is being tested at this location after it was requested by the community as a response to
a series of crashes that occurred at the intersection.

Pedestrian Signals and Phasing
The Burlington County engineering department implemented an exclusive pedestrian phase at
one intersection in downtown Mount Holly servicing pedestrian traffic between the ROW for the
main flow of traffic and the minor approach. With this it was hoped that the perception to the
pedestrians would be a shorter wait and it would encourage them to obey the signals. The
county went even further and installed “No Turn On Red” blank-out signs that are lit during the
pedestrian phase to eliminate conflicts with right turning vehicles during the exclusive pedestrian
phase.


At a second location in downtown Mount Holly, the county also implemented a pedestrian phase
that operates with a low volume driveway that is the fifth leg of an offset intersection. This has
eliminated most of the potential conflicts that could occur during a pedestrian crossing at this
location.

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In another case, in Springfield Township, at the intersection of CR 670 and Island Road, the
township had requested a traffic signal, however, an engineering study showed that a traffic
signal was not warranted and would decrease the efficiency of the intersection. The location
encountered an elementary school on one side of the road and the municipal building and
recreational facilities on the opposite side. Since it turned out all school children were bussed to
school, the location was not considered a school crossing. As a result, a pedestrian–actuated
flashing assembly instead of a traffic signal was implemented. This solution was the likely result
of MUTCD standards that do not indicate that a signal can be installed on the basis of
engineering judgement if it does not meet the volume criteria. Facilities adjacent to the roadway
indicate that there is a potential for pedestrian activity and that probably was the reason the
township had requested a signal. County engineering was, however, unable to justify such
since existing standards prioritize vehicular movements and efficiency of an intersection.


Burlington County generally installs two push buttons on each corner of a signalized intersection
regardless of whether there is a background cycle or the signal operates in a semi-actuated or
fully-actuated free mode. During the background cycles, half of the push buttons are in-
operable as the walk indication operates with the major traffic flow. However, during the free
plan the signal rests in the “DON’T WALK” phase until the push buttons are activated. This
method provides pedestrians with the full allocation of the pedestrian timing and also reduces
the wait for vehicles on the minor approaches when there is no pedestrian activity.


Burlington County engineers have also recognized the differences in walking speeds.
Typically, where there are many young children and/ or senior citizens, the County times signals
based upon a 3 feet/ second walking speed (instead of 4 feet/ second as recommended within
the MUTCD) and in addition calculates the crossing distance from curb to curb instead of the
more common calculation of curb to shoulder or curb to the middle of the furthest travel lane.


Morris County also seems to be more progressive in accommodating pedestrians. According to
a Morris County engineer, 3 feet/ second walking speed calculations have also been used near
senior citizen complexes, schools and hospitals.


All signals in Morris County have push buttons. The county uses the three section head
(red/amber/green) in most rural areas. In urban areas, the “Walk/ “Don’t Walk” text message
was used until the requirement changed to use the “hand/ man” indication. This signal is used

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whenever an established crosswalk exists at the intersection at the time the signal is installed,
or at the request of the municipality that the signal is located in.


Different from Burlington County, the “hand/ man” signals used in Morris are timed to allow the
pedestrian a minimum amount of time to cross to within half a lane width of the opposite curb
line. This time is the timing used for the flashing “hand” (don’t walk indication) portion of the
timing (clearance time). The amount of time the “man” (walk) indication is lit, is dependant upon
the amount of time allotted to that phase of the signal. It should be noted that the “man”
indication only appears if the pedestrian uses the push button. If they do not, the correct
amount of time will not be allotted to that phase of the signal.


Finally, Morris County engineering generally recommends using exclusive pedestrian signal
phases where pedestrian volumes dictate their need. However, thus far only one location in the
center of Morristown is known to have an exclusive pedestrian phase. At this location
pedestrian volumes are high and the layout of the intersection and the varied directions in which
people can cross dictated its installation.

Count-Down Signal
One of the new devices, countdown signals counting down the time
you have left before through traffic has the green (go) light,
supposedly give pedestrians enough time to cross the street. A
countdown signal was installed in Trenton adjacent to a senior
citizens complex. When the light turns red for oncoming traffic, the
pedestrian signal immediately starts counting down the seconds,
from 27 seconds.                                              Image: Graphic Illustration of Count-Down
                                                                 Signal. Source: www.walkinginfo.org

It is claimed that seniors have enough time to reach the median dividing the four-lane highway.
And, once at the median, they can press another button to get an additional 27 seconds to cross
the second part of the roadway. It is unclear whether this system has significantly enhanced the
crossing experience for pedestrians regarding the time it takes and the convenience. After all,
although about ten times as expensive, this system did not provide the seniors more time than
the traditional “Walk/ Don’t Walk” indication, it simply tells them exactly when the signal will
change. This system also seems more beneficial to traffic flow than to pedestrians. It is
claimed that pedestrians use the information to make better decisions about when to enter a

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crosswalk. On the other hand, however, one may also argue that people and especially the
elderly could misjudge the information and decide not to cross even though there would be
sufficient time left for them to cross. Especially at locations where we can expect many elderly
people to cross, consideration should first be given (but not be limited) to providing more time to
cross, reducing vehicular speeds and alerting motorists of pedestrians still in the crosswalk.

Moving Eyes
Not yet tested in New Jersey but in place in a few locations in Philadelphia, is the moving eye
signal, which features two large eyes that glance left and right to remind pedestrians to look
both ways before crossing. Though simple, according to a district traffic engineer for
Philadelphia, studies have shown that the device proves to be effective. The signal points out
the order where pedestrians have to pay attention and research has
shown that as the eyes glance left and right, the pedestrian watches.


                                                    Image: Graphic Illustration of Animated
                                                       Eyes. Source: www.walkinginfo.org

Additional Considerations

Alerting Pedestrians
Special warning signs and pavement markings designed to encourage or prompt pedestrians to
look for turning vehicles as they cross the street may help lower pedestrian collisions; an
Institute study found the use of sign prompts and crosswalk warning messages increased the
percentage of pedestrians looking for threats from turning vehicles and decreased the number
of conflicts between them.

Advanced Stop Lines
Other Institute research found that moving painted stop lines farther back from crosswalks than
the standard 4 feet resulted in a significant increase of drivers who stopped at least 4 feet from
the crosswalks and a significant decrease in the percentage of drivers who stopped within the
crosswalks.

Combined Measures
To have a traffic calming effect on vehicular movement, textured crosswalks by themselves are
not particularly effective, however, in conjunction with other measures such as bulbouts, raised


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crosswalks, and raised intersections, they can have a successful traffic calming effect. In
addition, area wide implementations rather than just spot improvements can be much more
effective in enhancing safety and comfort for pedestrians.
exclusive pedestrian signals should generally be considered.

Infrared and Microwave Detectors
Infrared detectors (passive detection) detect the presence of pedestrians in either the targeted
curbside area or within the crosswalk. The pedestrian entering the infrared detection zone
activates the walk indicator. Within the crosswalk the device detects the presence of individuals
requiring additional time to cross and accordingly extends the clearance interval and provides
more time to cross. This type of device can be beneficial when, due to extremely varied
characteristics and thus resulting speeds of pedestrians, establishing the right signal timing
becomes difficult.




       Images: Graphic Illustration of Infrared and Microwave Detectors. Source: www.walkinginfo.org


In these cases the predominate speed of the slower pedestrians may be used to control the
signals but cause unnecessary delays to motorists when slower pedestrians aren’t present.
Thus, infrared or microwave detectors can be good solutions in cases where pedestrian
characteristics are very diverse or unknown.

Traffic Signal Warrants
As mentioned earlier in this paper, per MUTCD national warrants, a requirement for installing a
traffic signal is that there are a certain number of pedestrians present (see section on Common
Practice, p. 6). However, these warrants ignore the fact that current roadway design

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discourages people from walking, and therefore dismisses the latent potential for moderate to
high pedestrian volumes (e.g. in rural town centers, school areas, retail/ commercial
establishments etc.). In addition, new developments such as recreational facilities, libraries,
stores, bike and walking paths, create new demand and signals should be installed in
conjunction with such new facilities based on projected crossing demand.


The National Pedestrian and Bicycle Information Center and the FHWA “Pedestrian Facilities
User Guide”iv, both emphasize when high pedestrian traffic exists (or is anticipated) during a
majority of the day, fixed-time signals should be used to consistently allow crossing
opportunities. Although pedestrian-activated/ actuated signals are common practice in New
Jersey, they should only be used when pedestrian crossings are intermittent.

Signal Timing
Shorter cycle lengths and longer WALK intervals generally provide better service to pedestrians
and encourage better signal compliance. And for optimal pedestrian service, fixed-time signal
operation usually works best. If push buttons are installed, quick response should be
incorporated into the system. They should also be well signed and fully accessible to
pedestrians in wheelchairs.

Exclusive Pedestrian Intervals
Exclusive pedestrian intervals stop traffic in all directions. This type of signal timing has proven
to reduce pedestrian crashes significantly especially in downtown locations with heavy
pedestrian volumes and slower speeds. However, unless quick in response and timed for
pedestrians (which may mean to take more time from vehicular phases), exclusive pedestrian
signals may continue to be ignored by pedestrians.

Leading Pedestrian Interval
A Leading Pedestrian Interval included in signals (LPI) has proven to be a very simple but useful
solution at pedestrian crossings. An LPI provides pedestrians an advanced walk signal before
the motorists get the green light, thus giving the pedestrian several seconds to proceed into the
crosswalk where there is a concurrent signal. A misperception is that leading pedestrian


iv
     Pedestrian and Bicycle Information Center, http://www.walkinginfo.org, Walking Design and Engineering
– Signals and Signs.

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intervals increase crash risks since they expose pedestrians to turning vehicles by giving them a
head start to cross the street. However, in contrast, the leading pedestrian interval 1) makes
the pedestrians much more visible to motorists and motorists more likely to yield to them, and 2)
ensures that the pedestrians get to cross when they have the legal right to do so and prevent
turning traffic to delay and intervene their crossing. Studies have demonstrated a reduction in
conflicts for pedestrians where leading pedestrian intervals have been used (e.g. New York
City). Although pedestrian lead signal phasing has been known to increase safety and
convenience for pedestrians, NJDOT does not use such signal phasing.

Other Signal Enhancements
Various other signal enhancements can also benefit pedestrians at crossings. These include
providing left turn phasing separate from pedestrian walk intervals (or LPI), timing signals in
sequence to encourage desired vehicle speeds, a brief all-red interval, avoidance of post-
mounted signals and right-turn-on-red (RTOR) restrictions.


Whereas most of these enhancements are self-explaining, the issues with post-mounted signals
and right-turn-on-red need further clarification.


Post-Mounted Signals
As per MUTCD, traffic signals are required both, on the near side and far side of an intersection.
The problem with far-side signals is that the focus of driver’s attention is directed away from
where pedestrians wait and attempt to cross. In addition, far-side signals allow motorists to
proceed into the crosswalk to wait for the “go” indication, rather than waiting at the stop line, and
clear the way for pedestrians. (The near-side signal requires drivers to stay behind the signal
and behind the crosswalk so that they can see the signal). The issue of motorists pulling into
the crosswalk is a tremendous concern of pedestrian safety, since people on foot are often
forced to walk around the nose of the car, exposing themselves to oncoming traffic. Signals in
general, but at minimum in downtown, busy pedestrian generating areas and school zones,
should only be placed on the near side of an intersection. Three significant safety benefits
could result for pedestrians: 1) cars would likely slow down further in advance of an intersection,
2) cars would stop in advance of the crosswalk rather than within it, and 3) if the signal was
placed on the side of the roadway, the view of drivers would lead towards the sidewalk and they
would better see when pedestrians attempt to cross.



Pedestrian and Bicycle Resource Project
Rutgers’ Voorhees Transportation Policy Institute                                          16
Review of Traffic Signal Standards and Striping Schemes
Accommodating Pedestrians in NJ                                                                3/20/02


Right-Turn-On-Red
RTOR permission was introduced in the 1970’s and has been found to sometimes have
detrimental effects on pedestrians, including creating safety hazards. A general problem with
the RTOR is that while the law requires motorists to come to a full stop and yield to cross street
traffic and pedestrians prior to turning, many motorists do not comply with the regulation.
Motorists are often very intent on looking for traffic approaching on their left; they are not alert to
pedestrians on their right. In addition motorists pull into the crosswalk to wait for a gap in the
traffic stream, thus intervening with pedestrian flow.


A recent study conducted by the Insurance Institute for Highway Safetyv, found that time of day
restrictions of RTOR (not in effect at hours with low pedestrian volumes e.g. at night) have the
potential to reduce crashes. However, due to safety benefits to pedestrians, all day RTOR
restrictions should principally apply where and/ or when there are high/ anticipated all-day
pedestrian volumes (e.g. downtown, near busy transit stops, etc.).


A concern that is often raised when RTOR is prohibited is that this may lead to higher RTOG
(right-turn-on-green) conflicts when there are concurrent signals. Use of the Lead Pedestrian
Interval can usually best address this issue. However, when pedestrian volumes (or anticipated
volumes) are high, exclusive pedestrian signals should generally be consideredvi.




Conclusion


The focus of pedestrian planning and engineering should be on enhancing the walking
experience through the elimination of safety hazards. Traditionally the focus has concentrated
on increasing pedestrian awareness and alerting them of faulty driver behavior. The scope
needs to be broadened. With enhanced crosswalk and signal technology, it is quite possible to
provide less-stressful and more meaningful enhancements to our roadways. Whereas traffic
signals and crosswalk striping schemes are an important component of these efforts, other
safety enhancements need to be considered. These other safety enhancements include but are

v
     Status Report, Insurance Institute for Highway Safety, Vol. 36, No. 4, April 2001, p.3.
vi
     www.Walkinginfo.org. Design and engineering: signals and signs: right turn on red.

Pedestrian and Bicycle Resource Project
Rutgers’ Voorhees Transportation Policy Institute                                                  17
Review of Traffic Signal Standards and Striping Schemes
Accommodating Pedestrians in NJ                                                      3/20/02


not limited to reducing traffic speeds in certain locations, traffic calming measures, reducing
crossing distances by narrowing travel lane width and/ or implementing bulb-out/ neckdowns at
crossings, center island median refugees and RTOR restrictions. These are proactive
measures rather than reactive measures that could have a profound impact on overall safety
and convenience for pedestrians.


Simply stated, if we take a holistic approach to enhancing pedestrian travel we will be
eliminating the hazards that impede safety, not just alerting the public (pedestrians and drivers)
to the hazards.




Pedestrian and Bicycle Resource Project
Rutgers’ Voorhees Transportation Policy Institute                                         18
Review of Traffic Signal Standards and Striping Schemes
Accommodating Pedestrians in NJ                                                                3/20/02



References


     •    Pedestrian Compatible Planning and Design Guidelines, New Jersey Department of
          Transportation, Trenton, NJ, April 1996.
     •    New Jersey Department of Transportation Roadway Design Manual, Trenton, NJ, updated
          January 2000.
     •    Manual on Uniform Traffic Control Devices 2000, Millennium Edition, U.S. Department of
          Transportation, Federal Highway Administration, Washington D.C., 2000.
     •    A Policy on Geometric Design of Highways and Streets, American Association of State Highway
          and Transportation Officials, Washington D.C., 1994.
     •    Richard L. Knoblauch, Martin T. Pietrucha, and Marsha Nitzburg, Field Studies of Pedestrian
          Walking Speed and Start-Up Time, Transportation Research Record No. 1538, Transportation
          Research Board, 1996.
     •    Staplin, L., Lococo, K., and Byington, S., Older Driver Highway Design Handbook (FHWA-RD-97-
          135) Federal Highway Administration, Washington DC, January 1998.
     •    Perils for Pedestrians, John Z. Wetmore, http://www.pedestrians.org/examples.htm
     •    Pedestrian and Bicycle Information Center, http://www.walkinginfo.org, Walking Design and
          Engineering – Signals and Signs.
     •    Status Report, Insurance Institute for Highway Safety, Vol. 36, No. 4, April 2001, p.3.
     •    www.Walkinginfo.org. Design and engineering: signals and signs: right turn on red.




Pedestrian and Bicycle Resource Project
Rutgers’ Voorhees Transportation Policy Institute                                                   19

								
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