KUNZMAN ASSOCIATES Traffic Engineering and Transportation Planning

Discussion of Current TRAFFIC ISSUES
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SUBJECT: Internally Illuminated Raised Pavement Markers

Internally Illuminated Raised Pavement Markers are also known as In-Pavement Flashing systems.

Internally Illuminated Raised Pavement Markers were first introduced nearly a decade ago in California. Today they are used primarily in California, and in a few other states. In the last few years their popularity has grown, but they are still rare.

Internally Illuminated Raised Pavement Markers are used in a variety of ways including to delineate curves to prevent cars from crossing the centerline, and in crosswalks.

They are typically yellow and flash. Flashing yellow means use caution and flashing red implies stop. Although stopping a vehicle may be the goal, a pavement marker should not be used as a STOP sign or traffic signal.

The cost for a crosswalk installation is about $30,000 but can vary by at least a factor of 2. Not only is location, and availability of installers a cost factor, but also traffic control, striping, sand or hydro blasting, and so forth are cost factors. Multiple installations at one time usually reduces cost per installation.

Internally Illuminated Raised Pavement Markers can either be permanently set on flash or they can be turned off and activated as the need arises either by a pedestrian push button for instance, or a presence detector. The ones which permanently flash can be either hard wired for an external energy source, or they can have an internal battery.

It is clear that Internally Illuminated Raised Pavement Markers will help the driver see either the curve in a roadway or the crosswalk, at least some of the time. And this clearly is a benefit. The devices are typically used above and beyond conventional treatments in problem locations.

The technology is new and is still being improved. There will be more and more applications and in varying designs and using varying control mechanisms beyond what we see today.

Internally Illuminated Raised Pavement Markers are recognized in the 2000 Manual of Uniform Traffic Control Devices where they are referred to as Internally Illuminated Raised Pavement Markers.

Internally Illuminated Raised Pavement Markers are not a cure all. They are not seen by everyone and some people may be confused by them.
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SUBJECT: Marked or Unmarked Crosswalks

The purpose of a painted crosswalk is to channel pedestrian crossings to one location versus another. Sounds simple, right?

But, many pedestrians view a painted crosswalk at an unsignalized intersection as a safe place to cross a street because the pedestrian has the right of way and the car is suppose to stop for the pedestrian.

Crosswalks come in two varieties. There are marked or painted crosswalks, and unmarked or unpainted crosswalks. There is a crosswalk at every intersection where there is a sidewalk, whether painted or not, unless there is a sign advising pedestrians not to cross. The definition of a crosswalk is the "prolongation or connection of the boundary lines of sidewalks at an intersection..." per the California Vehicle Code Section 275.

Whether the crosswalk is marked or unmarked is important. There is a substantial body of research that shows marking a crosswalk, rather than leaving it unmarked, in many cases increases the accident potential.

The reason this is the case is because a marked crosswalk is relatively hard for a driver to see even during day light hours, and is particularly hard to see at dawn or dusk, or at night, or during inclement weather.

On the other hand, the pedestrian in a marked crosswalk has a feeling of security since the cars are suppose to stop for a pedestrian in a crosswalk, and thus the pedestrian may feel that it is safe to proceed and walk out in front of an on-coming vehicle. The pedestrian assumes the driver sees the pedestrian and sees the crosswalk and will stop.

So whether to mark a crosswalk at an unsignalized intersection, and particularly whether to mark a mid-block crosswalk, is a difficult decision.

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www.traffic-engineer.com or www.traffic-expert.com

Kunzman Associates
1111 Town and Country Road, Suite 34
Orange, CA 92868