A pedestrian crossing or crosswalk is a designated point on a road at which some means are employed to assist pedestrians wishing to cross. They 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. 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.
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. Pedestrian crossings, especially when combined with other features like pedestrian priority or raised surfaces, can be used as a traffic calming technique.
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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, pedestrian scrambles (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 (or 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 are actually placebo buttons designed to give pedestrians an illusion of control while the crossing signal continues its operation as programmed.[1] This can also be witnessed at Anniesland Cross, a large road junction in Glasgow, Scotland. While each pedestrian crossing has a push button, all roads and pedestrian crossing run on a cycle and the pedestrian crossing will change only at the correct point of the cycle, whether the buttons are pushed or not.
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.[2]
In the United Kingdom and parts of the Commonwealth, 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, 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, a flashing yellow sequence begins for the motorist who can proceed through the crossing if safe to do so.
Other types of crossings also exist in Australia. The Zebra Crossing is common in low traffic areas. These crossings aren't usually controlled by signals. Belisha beacons are also commonly used for school crossings. Since most school crossings in the country are manned, these signals or beacons only serve as a warning to motorists.
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 traffic signal, 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, most laws require vehicles to either yield or even come to a complete stop right-of-way for a pedestrian or bicyclist who has entered, or is intending to enter the 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 to provide conspicuity against the backdrop of red, yellow, and green traffic lights. Modern signals generally use pictograms of an red hand and a green 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.
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].
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 Washington, D.C.) and other cities around the United States, and the current draft update of the Manual on Uniform Traffic Control Devices (MUTCD) will require that countdown signals be used at all intersections within 10 years of the manual being adopted (anticipated early 2010).
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". Contrary to popular belief that the buttons are placebos,[3] most buttons do work, but some only at certain times of day and even certain times of the year. In an event that the pedestrian button is malfunctioning, the pedestrian signal will be always given automatically until the button is repaired.
Legally speaking, in most states crosswalks exist at all intersections meeting at approximately right angles, whether they are marked or not.[4] Some states, such as California, have pedestrian safety laws requiring cars to stop for pedestrians in both marked and unmarked crosswalks.[5]
In most states, drivers only have to wait until the pedestrian has finished crossing the half of the crosswalk that the driver in 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.
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.
In Mexico City, 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.
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.[6]
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.[7] 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.
Pedestrian crossings across railways may be arranged diffently, such as in New South Wales. Here they consist of
In France, when a train coming a red man brighten with the word STOP flashing red.
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