Pedestrian crossing

A pedestrian crossing is a place designated for pedestrians to cross a road, street or avenue. The term "pedestrian crossing" is also used in the Vienna and Geneva Conventions, both of which pertain to road signs and road 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 or where vulnerable road users 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, and in other areas, jaywalking laws are in place which restrict pedestrians from crossing away from marked crossing facilities. Even in some jurisdictions with jaywalking laws, unmarked pedestrian crossings are assumed to exist at every intersection unless prohibited by signage.
Pedestrian crossings using signals clearly separate when each type of traffic can use the crossing. Crossings without signals generally assist pedestrians, and usually prioritise pedestrians, depending on the locality. Pelican crossings use signals to keep pedestrians together where they can be seen by motorists, and where they can cross most safely across the flow of vehicular traffic, whereas zebra crossings are uncontrolled and more appropriate for lower flow numbers. What appears 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.

History

The first pedestrian crossing signal was erected in London in December 1868. It was installed to allow pedestrians, especially Members of Parliament hurrying to vote, to cross Bridge Street to reach the Parliamentary Estate. It was the idea of John Peake Knight, a railway engineer. The signal consisted of three semaphore arms surmounted by a gas lantern which at night showed green and red aspects as appropriate to pedestrians and those on the carriageway. The semaphore arms were raised and lowered manually by a police constable who would rotate a handle on the side of the pole. However, in January 1869, the gas 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 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 vehicles 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.

On October 31, 1951, in the town of Slough, west of London, the first pedestrian crossing in history was marked. The black and white striped crossings were dubbed "zebra crossings", and the Ministry of Transport had installed 1,000 experimental versions across the UK in 1949 during a "Pedestrian Safety Week". The exact source of the name "zebra crossing" cannot be confirmed with certainty, but it is believed that it came from the visual similarity of the crossing with the stripes on zebra fur. It is believed that the term "zebra crossing" was first used by British politician and military officer James Callaghan.
According to Zegeer,

Pedestrians have a right to cross roads safely and, therefore, planners and engineers have a professional responsibility to plan, design, and install safe crossing facilities.

Criteria

Pedestrian crossing warrants are guidelines for the appropriate pedestrian crossing type for a site's traffic conditions. There are several guidelines in use across the world, and guidance and practice differ between jurisdictions. An over-emphasis by traffic engineers on vehicular movement in these criteria is criticised for neglecting the safety of pedestrians.
In some jurisdictions, the decision to mark a crossing is given a quantitative veneer through formulae such as PV², a prescription developed in the United Kingdom in 1987 and later expanded to India and Iran. Under this prescription, the pedestrian traffic volume rate P and vehicle traffic volume rate V are both estimated during peak hours, and the product PV² is used to determine which type of crossing, if any, should be installed. For example, if 500 pedestrians cross the road per hour and 600 vehicles per hour use that road section, the resulting PV² of 1.8×10⁸ pedestrian×vehicle²/hr³ dictates that a pelican crossing should be installed.
The US Manual on Uniform Traffic Control Devices advises that crosswalk markings should 'not be used indiscriminately' and encourages engineering studies at sites away from signalized intersections and STOP or Yield signs. It admonishes against crossing markings on high-traffic routes if the speed limit exceeds. The Manual is criticised for enabling motorist-focused traffic engineers to avoid implementing street safety measures.
Tactical urbanist groups implement guerrilla crosswalks by public nomination, especially at junctions where nominations for marked crossings via formal channels have been repeatedly ignored by city government, or where the government's stated timeline for marking a crossing is implausibly long. In Los Angeles, a low-intensity conflict between the government and the guerrilla groups frequently results in the removal of the guerrilla crosswalks, although a few are normalised; occasionally, city police have arrested guerrillas.

Types and design

Type	Image	Description	Notes
Informal crossings		Crossings giving equal priority to pedestrian and vehicular traffic.	A refuge is sometimes installed so that a pedestrian can cross in two stages; called 'unmarked crosswalk' in North America.
Zebra crossing		Formed of black and white stripes. Pedestrians normally have priority over vehicular traffic.	Called a 'marked crosswalk' in North America.
Signal-controlled crossing		Crossing with call buttons, pedestrian signals, and traffic lights, HAWK beacons, or Rectangular Rapid Flashing Beacons for vehicular traffic.	Sometimes known as a 'pelican crossing'
Multi-user crossing		Crossings allowed to be used by non-pedestrians, such as cyclists or horse riders.	Sometimes known as 'toucan crossing'
Pedestrian underpass		A pedestrian pathway in a tunnel under a road, providing a crossing without interrupting pedestrian or vehicular traffic.	Also known as a subway.
Pedestrian overpass		Footbridge over a pedestrian pathway, allowing pedestrians to cross without interrupting vehicular traffic.	Also known as a footbridge.

Unmarked crossings

In some countries, including the US, "unmarked crosswalks" are presumed to occur at intersections even if a crossing is not marked, except at locations where pedestrian crossing is expressly prohibited.
Pedestrian refuges are uncontrolled crossings with two dropped kerbs and a central traffic island, protected by kerbs. The island allows pedestrians to cross the road one direction of traffic at a time, which can be quicker and safer than a lack of crossing. Additionally, they can narrow the road, slowing down vehicles and preventing them from overtaking. However, they may not afford pedestrians priority, meaning pedestrians may have a longer wait than a controlled crossing. They can also create pinch points, which can be dangerous for cyclists.
Courtesy crossings are uncontrolled crossings with coloured surfacing or some other non-formal suggestion that pedestrians may cross. They aim to encourage concentrated pedestrian crossings and to encourage drivers to let pedestrians cross the roads out of courtesy, rather than obligation. The inclusion of stripes, the presence of narrowing and visual narrowings of the road positively affect courtesy.

Marked crossings

The simplest marked crossings may just consist of some markings on the road surface. In the US these are known as "marked crosswalks". In the UK these are often called zebra crossings, referring to the alternate white and black stripes painted on the road surface. If the pedestrian has priority over vehicular traffic when using the crossing, then they have an incentive to use the crossing instead of crossing the road at other places. In some countries, pedestrians may not have priority, but may be committing an offence if they cross the road elsewhere, or "jaywalk". 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 cross striping machines are special equipment professionally used to paint zebra lines on the intersections or other busy road sections. Because of the characteristics of zebra crossings, parallel stripes that are wide but not long, the striping machine is often a small hand-guided road marking machine, which can easily be made to change direction. There are differences between the engineering regulations in different countries. The marking shoe of a pedestrian cross striping machine, which determines marking lines' width, is much wider than on other marking machines. A smaller marking shoe with wheels may be used to perform the road striping.
The section of road should be swept clean and kept dry. The painter first pulls a guiding line straight and fix the two ends on the ground. Then they spray or brush a primer layer on the asphalt or concrete surface. The thermoplastic paint in powder form is then melted into a molten liquid state for painting. Finally, the painter pulls or pushes the striping machine with the guide rod along the guiding line. As an alternative to thermoplastics, household paint or epoxy can be used to mark crosswalks.