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A pedestrian crossing or crosswalk is a place designated for pedestrians to cross a road. Crosswalks are designed to keep pedestrians together where they can be seen by motorists, and where they can cross most safely across the flow of vehicular traffic.
Marked pedestrian crossings are often found at intersections, but may also be at other points on busy roads that would otherwise be too unsafe to cross without assistance due to vehicle numbers, speed or road widths. They are also commonly installed where large numbers of pedestrians are attempting to cross (such as in shopping areas) or where vulnerable road users (such as school children) regularly cross. Rules govern usage of the pedestrian crossings to ensure safety; for example, in some areas, the pedestrian must be more than halfway across the crosswalk before the driver proceeds.
Signalised pedestrian crossings clearly separate when each type of traffic (pedestrians or road vehicles) can use the crossing. Unsignalized crossings generally assist pedestrians, and usually prioritise pedestrians, depending on the locality. What appear to be just pedestrian crossings can also be created largely as a traffic calming technique, especially when combined with other features like pedestrian priority, refuge islands, or raised surfaces.
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Pedestrian crossings already existed more than 2000 years ago, as can be seen in the ruins of Pompeii. Blocks raised on the road allowed pedestrians to cross the street without having to step onto the road itself which doubled up as Pompeii's drainage and sewage disposal system. The spaces between the blocks allowed horse-drawn carts to pass along the road.
The first pedestrian crossing signal was erected in Bridge Street, Westminster, London in December 1868. It was the idea of John Peak Knight, a railway engineer, who thought that it would provide a means to safely allow pedestrians to cross this busy thoroughfare. The signal consisted of a semaphore arm (Manufactured by Saxby and Farmer, who were railway signaling makers), which was raised and lowered manually by a police constable who would rotate a handle on the side of the pole. The semaphore arms were augmented by gas illuminated lights at the top (green and red) to increase visibility of the signal at night. However, in January 1869, the gas used to illuminate the lights at the top leaked and caused an explosion, injuring the police operator. No further work was done on signalled pedestrian crossings until fifty years later.
In the early days of the 20th century car traffic increased dramatically. A reader of The Times wrote to the editor in 1911:
"Could you do something to help the pedestrian to recover the old margin of safety on our common streets and roads? It is heartrending to read of the fearful deaths taking place. If a pedestrian now has even one hesitation or failure the chance of escape from a dreadful death is now much less than when all vehilcles were much slower. There is, too, in the motor traffic an evident desire not to slow down before the last moment. It is surely a scandal that on the common ways there should be undue apprehension in the minds of the weakest users of them. While the streets and roads are for all, of necessity the pedestrians, and the feeblest of these, should receive the supreme consideration."
|The examples and perspective in this article deal primarily with North America and do not represent a worldwide view of the subject. (August 2013)|
Crossings are of various types.
Special markings are often made on the road surface, both to direct pedestrians and to prevent motorists from stopping vehicles in the way of foot traffic. There are many varieties of signal and marking layouts around the world and even within single countries. In the United States, there are many inconsistencies, although the variations are usually minor. There are several distinct types in the United Kingdom, each with their own name.
Pedestrian refuges or small islands in the middle of a street may be added when a street is very wide, as these crossings can be too long for some individuals to cross in one cycle. In places where there is very high pedestrian traffic, exclusive traffic signal phases for pedestrians (also known as Barnes Dances) may be used, which stop vehicular traffic in all directions at the same time. Another relatively widespread variation is the curb/kerb extension (also known as a bulb-out) which narrows the width of the street and is used in combination with crosswalk markings.
Reports suggest that many walk buttons in some areas, such as New York City and the United Kingdom, may actually be placebo buttons designed to give pedestrians an illusion of control while the crossing signal continues its operation as programmed. In New York City, many such buttons are now rendered useless due to the automatic programming of the crosswalk, and other buttons may work, but only at certain times of day or certain periods of the year. In the United Kingdom, pressing a button at a standalone pedestrian crossing that is unconnected to a junction will turn a traffic light red, but this is not necessarily the case at a junction.
In the United States, crosswalks are sometimes marked with white stripes, though many municipalities have slightly different methods, styles, or patterns for doing so, and the styles may vary over time as intersections are built and reconstructed. There are two main methods for road markings in the United States. Most frequently, they are marked with two thick white lines running from one side of the road to the other. A third "stop line", which is very thick and extends only across lanes going into the intersection, is usually also present. Left-turn stop lines are often set further back, to avoid conflict with left-turning traffic coming from the roadway on the right. The stop line acts as the legally mandated stopping point for vehicles, and discourages drivers from stopping in the middle of the crosswalk. The other method involves the use of the more easily visible continental stripes (like UK zebra crossings), which are becoming more popular in place of the two-line variant. The designs used vary widely between jurisdictions, and often vary even between a city and its county (or local equivalents). Where a road forms part of a city limit or other such political boundary—thus making the intersection shared between the two—there may be more than one design used on different sides, depending upon which government painted it.
Marked crosswalks are usually placed at traffic intersections or crossroads, but are occasionally used at mid-block locations where pedestrian generators are present such as at transit stops, schools, retail, or housing destinations. In the United States, these so-called "mid-block" crossings may include additional regulatory signage such as "PED XING" (for "pedestrian crossing"), flashing yellow beacons, stop or yield signs, or by actuated or automatic signals. Some more innovative crossing treatments include in-pavement flashers, yellow flashing warning lights installed in the roadway, or HAWK beacon, an overhead signal with two pair of red beacons above an amber beacon, when a pedestrian is detected or actuates the device it begins a sequence of amber flashing followed by a solid red [when vehicles may not cross], followed by a flashing red phase that allows motorists to proceed, only if the pedestrian[s] are clear of the travel way. In the United States, crossing laws vary from state to state and sometimes at the local level. All states require vehicles to yield to a pedestrian who has entered a marked crosswalk.
At crossings controlled by signals, the most common variety is arranged like this: At each end of a crosswalk, the poles which hold the traffic lights also have white "walk" and Portland Orange "don't walk" signs. These particular colors are used in North America (excluding Ontario and Quebec)to provide conspicuity against the backdrop of red, yellow, and green traffic lights. Modern signals generally use pictograms of an orange upraised hand and a white walking pedestrian rather than words. As a warning, the "don't walk" or hand signals begin to blink when the transition to "don't walk" is imminent. This normally occurs several seconds before the light turns yellow, usually going solid orange when the traffic light turns yellow. Some signals continue flashing the hand/"don't walk" phase during the yellow light, and go steady at red. Sometimes the "walk" signal does not come on in a steady pattern; it will sometimes blink/flash on and off instead to warn pedestrians to cross the street with caution due to the possibility of a turning vehicle. On pedestrian signals displaying text, "don't walk" is spelled without an apostrophe so that it fits easily on the sign. A black baffle is customarily placed in front of the lights to shield them from the sun and increase their visibility, as well as protect them from damage.
Legally speaking, in most states crosswalks exist at all intersections meeting at approximately right angles, whether they are marked or not. All states except Maine and Michigan require vehicles to yield to a pedestrian who has entered an unmarked crosswalk.
Crosswalks have also been adapted for the blind by adding accessible pedestrian signals [APS] that include two small distinct speakers at the actuator for each crossing location. The current accepted APS units have a continuous audible chirp that is easy to detect from a close distance but is not so loud as to be intrusive to neighboring properties [originally many versions of audible pedestrian signals used extremely loud buzzers or even bird-like whistles to convey information, the new standards have improved upon some of these earlier devices].
In the United Kingdom and certain parts of the Commonwealth of Nations, animal names are often used to distinguish several types of such crossings:
Belisha beacons are found at zebra crossings. The other types of crossing use coloured pictogram lights, depending on the intended users of the crossing this will be a man, a bicycle or a horse.
In Australia, the terminology pedestrian crossing is used.
Pictograms are standard on all traffic light controlled crossings. Like some other countries, a flashing red sequence is used prior to steady red to clear pedestrians. Moments after, in some instances, a flashing yellow sequence (for motorists) can begin indicating that the vehicles may proceed through the crossing if safe to do so; this is fairly uncommon however. 'Zig zag' lines are not used. In districts with heavier traffic warranting the use of a traffic light such as inner city areas, the equivalent of the US 'standard' configuration is used.
Only one usage derived from animal terminology is present in Australia, the Zebra Crossing. Given the lack of a traffic light, these are common in low traffic areas and aren't usually controlled by signals.
Reflector signposting is used at crossings in school zones, however given that most school crossings in the country are manned, these signs only serve as a warning to motorists.
Some pedestrian signals integrate a countdown timer, showing how many seconds are remaining for the crossing phase. These signals have been piloted in many cities (such as San Francisco, Boston, Las Vegas, Washington DC, Detroit, Albany, New York City, and Baltimore) and other cities around the United States. The 2009 edition of the Manual on Uniform Traffic Control Devices (MUTCD) requires countdown signals be used at all signalized intersections with pedestrian clearance intervals (flashing upraised hand phases) longer than 7 seconds. These, along with the current movement for wider smart traffic lights implementation, are anticipated to help improve the safety and overall smoothness of traffic on roads.
In some cities, other methods of pedestrian detection are being tested, including infrared and microwave technology, as well as weight sensors built in at curbside. On fully actuated signals, or semi-actuated traffic signals, pressing the button to cross a smaller side street will cause an "instant walk signal".
In most states, drivers only have to wait until the pedestrian has finished crossing the half of the crosswalk that the driver is driving on, after which the driver may proceed. In some states, such as Utah, if the driver is in a school zone with the lights flashing, the driver must wait until the entire crosswalk is clear before he may proceed. To gain the right-of-way in some parts of Canada, the pedestrian holds out his hand in a position much like that used to shake hands, and steps off the curb.
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In Mexico City, as in São Paulo, Brazil, the walking man moves his feet.
In Taiwan there is generally no crossing manner. The majority of crossings cannot be controlled by pedestrians, although there are exceptions in Taipei. All the crossings feature animated men who will walk faster immediately before the traffic signal will change. There is also always a countdown timer to inform the pedestrian how long they have left to cross. However, many motorists will ignore the crossing and continue driving even if pedestrians are crossing it.
In some countries, instead of "don't walk", a depiction of a red man or hand indicating when not to cross, the drawing of the person crossing appears with an "X" drawn over it.
Some countries around the Baltic Sea in Scandinavia duplicate the red light. Instead of one red light, there are two which both illuminate at the same time.
In many parts of eastern Germany, the design of the crossing man (Ampelmännchen) has a hat.
Pedestrian controlled crossings are sometimes provided with enhanced features to assist the disabled (disabled people). Enhancements may include:
There are two types of crosswalk lights: those that illuminate the whole crosswalk area, and warning lights.
The Illuminating Engineering Society of North America currently provides engineering design standards for highway lighting. In the USA in conventional intersections, area lighting is typically provided by pole-mounted luminaires. These systems illuminate the crosswalk as well as surrounding areas, and do not always provide enough contrast between the pedestrian and his or her background.
There have been many efforts to create lighting scenarios that offer better nighttime illumination in crosswalks. Some innovative concepts include:
In areas with heavy snowfall, using in-pavement lighting can be problematic, since snow can obscure the lights, and snowplows can damage them.
In certain circumstances, there are needs to install temporary pedestrian crossing signals. The reasons may include redirecting traffics due to roadworks, closing of the permanent crossing signals due to repairs or upgrades, and establishing new pedestrian crossings for the duration of large public events.
The temporary pedestrian crossings can be integrated into portable traffic signals that may be used during the roadworks, or it can be stand-alone just to stop vehicles to allow pedestrians to safely cross the road without directing vehicle movements. When using the temporary pedestrian crossings signals for roadworks, there should be consideration on signal cycle time. The pedestrian crossing cycles may add longer delay to the traffics which may require additional planning on road work traffic flows.
Depending on the duration and the nature of the temporary signals, the equipment can be installed in different way. One way is to use the permanent traffic signals mounted temporary poles such as poles in concrete-filled barrels. Another way is to use portable pedestrian crossing signals.
Fences in the footpath approaching the crossing force pedestrians and bicycles to slow down to navigate a zigzag path, which also tends to force that user to lookout for the train.
Pedestrian crossings across railways may be arranged differently, such as in New South Wales. Here they consist of
In France, when a train is approaching, a red man is shown with the word STOP flashing in red (R25 signal).
The safety of unsignalled pedestrian or zebra crossings is somewhat contested in traffic engineering circles.
Research undertaken in New Zealand showed that a zebra crossing without other safety features on average increases pedestrian crashes by 28% compared to a location without crossings. However, if combined with (placed on top of) a speed table, zebra crossings were found to reduce pedestrian crashes by 80%.
A five-year U.S. study of 1000 marked crosswalks and 1000 unmarked comparison sites found that on most roads, the difference in safety performance of marked and unmarked crossings is not statistically significant, unless additional safety features are used. On multilane roads carrying over 12,000 vehicles per day, a marked crosswalk is likely to have worse safety performance than an otherwise similar unmarked location, unless safety features such as raised median refuges or pedestrian beacons are also installed. On multilane roads carrying over 15,000 vehicles per day, a marked crosswalk is likely to have worse safety performance than an unmarked location, even if raised median refuges are provided. The marking pattern had no significant effect on safety. This study only included locations where vehicle traffic was not controlled by a signal or stop sign.
The Queensland government no longer builds pedestrian crossings due to safety concerns, preferring pedestrian refuges instead.
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