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Level crossing - Wikipedia, the free encyclopedia

Level crossing

From Wikipedia, the free encyclopedia

An automatic level crossing in France, with half-barriers, flashing lights and a bell.
An automatic level crossing in France, with half-barriers, flashing lights and a bell.

The term level crossing (also called a railroad crossing, road through railroad, railway crossing, train crossing or grade crossing) is a crossing on one level ("at-grade intersection") — without recourse to a bridge or tunnel — of a railway line by a road, path, or another railroad. It also applies when a light rail line with separate right-of-way (or a reserved track tramway) crosses a road.

Contents

[edit] Safety

A level crossing at Chertsey, England, as the barriers rise.
A level crossing at Chertsey, England, as the barriers rise.
A level crossing with flashing lights but no barriers on the Tyne and Wear Metro, England.
A level crossing with flashing lights but no barriers on the Tyne and Wear Metro, England.
A level crossing on China National Highway 109 in Beijing, China.
A level crossing on China National Highway 109 in Beijing, China.
A level crossing in Vancouver, BC where there are trolley wires above the roadway.
A level crossing in Vancouver, BC where there are trolley wires above the roadway.
A level crossing at Diemen railway station in the Netherlands. Trains run on the right, and the platforms are after the crossing in each direction.
A level crossing at Diemen railway station in the Netherlands. Trains run on the right, and the platforms are after the crossing in each direction.
A rural level crossing in Western Australia. Notice the "Railway Crossing" wording used on the crossbuck, as distinct from the "Railroad Crossing" seen in the United States.
A rural level crossing in Western Australia. Notice the "Railway Crossing" wording used on the crossbuck, as distinct from the "Railroad Crossing" seen in the United States.
A manually-operated level crossing in India.
A manually-operated level crossing in India.
A Finnish railroad crossing at Järilä, Kokemäki
A Finnish railroad crossing at Järilä, Kokemäki

Early level crossings had a flagman in a nearby booth who would, on the approach of a train, wave a red flag or lantern to stop all traffic and clear the tracks. Manual or electrical closable gates that barricaded the roadway were later introduced. The gates were intended to be a complete barrier against intrusion of any road traffic onto the railway. In the early days of the railways much road traffic was horsedrawn or included livestock. It was thus necessary to provide a real barrier. Thus, crossing gates, when closed to road traffic, crossed the entire width of the road. When opened to allow road users to cross the line, the gates were swung across the width of the railway, preventing any pedestrians or animals getting onto the line. The first U.S. patent for such crossing gates was awarded on August 27, 1867, to J. Nason and J. F. Wilson, both of Boston, Massachusetts.[1]

With the appearance of motor vehicles, this barrier became less and less effective and the need for a barrier to livestock diminished dramatically. Many countries therefore substituted the gated crossings with less strong but highly visible barriers and relied upon road users following the associated warning signals to stop.

In many countries, level crossings on less important roads and railway lines are often "open" or "uncontrolled", sometimes with warning lights or bells to warn of approaching trains. Ungated crossings represent a safety issue; many accidents have occurred due to failure to notice or obey the warning. Railways in the United States are adding reflectors to the side of each train car to help prevent accidents at level crossings. In some countries, such as Ireland, instead of an open crossing there may be manually operated gates, which the motorist must open and close. These too have significant risks, as they are unsafe to use without possessing a knowledge of the train timetable: motorists may be instructed to telephone the railway signaller, but may not always do so.

The director of rail safety at the UK Railway Inspectorate commented in 2004 that "the use of level crossings contributes the greatest potential for catastrophic risk on the railways." Eighteen people were killed in the UK on level crossings in 2003-4. Bridges and tunnels are now favoured, but this can be impractical in flat countryside where there is insufficient space to build a roadway embankment or tunnel (because of nearby buildings).

At railway stations a pedestrian level crossing is sometimes provided to allow passengers to reach other platforms in the absence of an underpass or bridge.

Where third rail systems have level crossings, there is a gap in the third rail over the level crossing, but the power supply is not interrupted since trains have current collectors on multiple cars.

[edit] Crossings around the world

[edit] Australia

Australian railroading generally follows United States practice, and has increasingly been employing American-made crossing warning equipment, such as grade crossing predictors, which attempt to provide a consistent amount of warning time for a trains of widely varying speeds.

One recent innovation in Australia is to provide crossbucks with flashing yellow lights at a distance from the level crossing itself, particularly where there are curves and visibility problems.

In Melbourne, Australia, there are several level crossings where the electrified train tracks cross roads with electrified tram tracks. These crossings are fitted with equipment to change the voltage supplied to the overhead wiring depending on the vehicle using the crossing at that point in time. Trains are severely speed-limited across these intersections.

Although all cases where a train line crosses a road are level crossings whether or not they are signed, a tram track in its own right of way crossing a road can also be a level crossing if it is signed with a crossbuck which can read either "TRAM WAY CROSSING" or "RAIL WAY CROSSING". Otherwise, it is a regular intersection and usually has either traffic lights or a give way sign facing the road.

[edit] Belgium

At a level crossing, any overhead electric power cables must also cross. This led to a conflict where a mainline railway that crossed one of the country's once extensive interurban tramlines (vicinal or buurtspoorweg) was electrified. In at least one location, this led to the tram overhead being dismantled.

Automatic Level crossings in Belgium have two red lights, an amber light and sometimes barriers. However, the amber flashes for a second every certain number of seconds just to inform drivers and pedestrians that they don't need to check if a train is coming, if the amber light is absent you proceed at your own risk.

[edit] Canada

Grade crossing protection practices in Canada are virtually identical to those in the United States (see below) using the same alternating flashing red lights and gate arms. The only significant differences are the crossbucks, which have no wording but are white with a red outline, and the advance-warning sign, which is a yellow diamond shape with a diagram of a track crossing a straight segment of road (similar to a crossroads sign, except that the horizontal road is replaced by a track). Before changes in regulations mandated bilingual (English and French) or no-wording signs, crossbucks were nearly identical to those in the States, except that they read "Railway Crossing" instead of "Railroad Crossing."

[edit] Italy

The cable-hauled section of the tramway up the hill from Trieste to Opicina has an interesting level crossing with a minor road at midpoint. As well as the rails, people crossing have to step or drive over two haulage cables, separated by wooden planking.

[edit] New Zealand

On the Taieri Gorge line, and in two places on the Hokitika Branch, in rural South Island, New Zealand, roads and railways share the same bridge when crossing a river; the rails are in the road and both motorists and the train driver must ensure that the bridge is clear, end to end, before starting to cross.

[edit] East and Southeast Asia

Level crossings in China, Thailand, and Malaysia are still largely manually-operated, where the barriers are lowered using a manual switch when trains approach. A significant number of crossings are without barriers.

[edit] Taiwan

As most railways in Taiwan were built during Japanese administration, railway level crossings remain very common, though many urban crossings have been eliminated when the railroads have been moved underground, e.g., segments of the Western Line in Taipei City, or abolished, e.g. the former Danshui TRA Line that is now the DanShui Line of the Taipei Rapid Transit System with no level crossings.

The Act Governing the Punishment of Violation of Road traffic Regulations (zh:道路交通管理處罰條例) defines three types of railway level crossing violations:

  1. Not obeying a direction of a flagman or insisting to cross when the gate starts lowering or when the bell rings or the (alternate red) lights flash is a violation for drivers of motorized and non-motorized vehicles and pedestrians.
  2. Directly crossing a railway level crossing not guarded by any flagman, gate, bell, or flashing light equipment without stopping as required when a warning sign is present is also a violation for drivers of motorized and non-motorized vehicles and pedestrians.
  3. Overtaking, making a U-turn, backing up, stopping or parking on a railway level crossing is a violation for drivers of motorized and non-motorized vehicles but not pedestrians.

The same Act provides different penalties against different types of railway level crossing violators as follows, with very heavy penalties against drivers of motorized vehicles and much lighter penalties against drivers of non-motorized vehicles and pedestrians:

  • Article 54: A driver of a motor vehicle shall be administratively fined 6000 to 12000 new Taiwan dollars for a railway level crossing violation. Should an accident occur, the driver license shall also be revoked, which is for life pursuant to Article 67. This lifetime revocation used to be absolute, but the amendment of the law proclaimed on 28 December 2005 and effective on 1 July 2006 has allowed a possible waiver after serving at least 6 years of the revocation.
  • Article 75: A driver of a non-motorized vehicle (e.g., a bicycle) shall be administratively fined 1200 to 2400 New Taiwan dollars for a railway level crossing violation.
  • Article 80: A pedestrian shall be administratively fined 1200 New Taiwan dollars for a railway level crossing violation.

Accidents at railway level crossings remain a very serious concern. The Taiwan Railway Administration alone has hundreds of level crossings along its routes of slightly more than 1100 km. In average, there is a level crossing in less than 2 km.[2][3]

Red emergency buttons have been installed to allow the public to report an emergency at a level crossing, such as stalled vehicles or any obstacles that would be very dangerous should any train approach.[4] However, willfully misusing the emergency button is a criminal offense. In an emergency, the public is asked to:

  1. First, press the button and be sure of its activation with a flashing light.
  2. Second, try to clear any obstacles, including any vehicles.
  3. Third, if unable to clear the obstacles and the warning bell rings, leave quickly. "A train is coming and please quickly leave the level crossing" will be announced in Mandarin, Taiwanese and Hakka.

[edit] United Kingdom

British Rail sign at Manor Road railway station in Hoylake, United Kingdom, indicating dangers of (mis-)using crossing and the financial penalty for not protecting it after use.
British Rail sign at Manor Road railway station in Hoylake, United Kingdom, indicating dangers of (mis-)using crossing and the financial penalty for not protecting it after use.

There are 8200 level crossings remaining in the United Kingdom in 2005. Of these, 1600 are road crossings. This number is gradually being reduced as the risk of accident at level crossings is considered high. The director of the Health and Safety Executive commented in 2004 that "the use of level crossings contributes the greatest potential for catastrophic risk on the railways."[5] Bridges and tunnels are now favoured, and there is a commitment on the part of UK rail authorities not to build new level crossings, and to reduce the number of existing level crossings. The cost of making significant reductions, other than by simply closing the crossings, is substantial, and a number of commentators argue that the money could be better spent. Some 6500 crossings are user-worked crossings or footpaths with very low usage. The removal of crossings can also improve train performance as some crossings have low rail speed limits enforced on them to protect road users.

In November 2004 there were two major accidents on UK level crossings: one involved a car driver committing suicide, who caused the death of seven people (Ufton Nervet rail crash); another involving a train carrying 50 school children resulted in no fatalities but a number of injuries. These incidents have increased efforts to review the placing of level crossings and to eliminate them where this is practicable. In the UK it has also been suggested that cameras similar to the type used to detect drivers who run traffic lights be deployed at level crossings, and that penalties for ignoring signals should be much more severe. A particular problem has been that the responsibility for the road safety at crossings is entirely outside the control of the railways. In 2006 legislative activities are in progress to permit Network Rail to be involved in the road side safety of crossings. This will allow the introduction of anti-slip surfaces and also barriers to prevent motorists driving around crossing arms and, it is hoped, reduce the number of crossing related deaths.

In the United Kingdom, major crossings were normally situated within easy viewing distance of a signal box, and usually directly adjacent to the signal box. This ensured that the signalman could verify that the road was clear before allowing a train onto the crossing. Many gated crossings have been replaced by lifting barriers, which are easier to mechanise. "Full barriers" consist of barriers each side of the track, which block the full width of the road and "half barriers" consist of a single arm each side of the road, which block only oncoming traffic. Half barriers were considered to have an advantage as motorists are less likely to be stranded on the crossing and unable to exit, but cases where impatient motorists have driven around the barriers have raised safety concerns. Video cameras are now often used at crossings to allow the human operator to be some distance from the crossing. On lightly-used railways many crossings are sited next to station stops or other stopping points and are crew operated. The guard pushes a plunger to operate the crossing. On completion of the crossing sequence, an indicator light permits the train to proceed if the crossing is observed by the train driver to be clear. After the train has cleared the crossing, it re-opens to road traffic.

To ensure that the barriers are noticed and to draw attention, public road crossings may be fitted with a ringing warning bell or siren and with lights. Some crossings also have a telephone which connects to the relevant signal box so that in case of an emergency the signalman's attention can be drawn promptly to the hazard and action can be taken. Some "automatic open crossings", with warning lights and bells but no barriers, were introduced, but their expansion was largely halted after the Lockington rail crash. Some smaller crossings, particularly pedestrian crossings on low-speed lines consist of nothing but a warning sign and raised pathway across the track itself.

The use of pedestrian crossings at stations is now rare, although historically it was common that passengers walked across the line between platforms on branch lines. At Settle, for example, before the footbridge was installed in the 1990s, the time taken while passengers from Leeds walked across the line was happily used to top up the driver's kettle with hot water. With a few exceptions, such as at Carmarthen, the remaining examples occur only on heritage railways or as a means for passengers who cannot climb stairs to move between platforms where the only other route is a footbridge.

For the episode of British motoring show Top Gear on the 25 February 2007, Network Rail staged a mock train crash in which an old locomotive was driven into a Renault Espace at around 80mph to graphically illustrate the dangers of "running the risk". There is a video of this scene shown posted on YouTube [1]

[edit] United States

An example of a typical rail crossing in the United States.
An example of a typical rail crossing in the United States.
A railroad crossing in Belton, MO, with only the crossbuck, flashing lights, and warning bell
A railroad crossing in Belton, MO, with only the crossbuck, flashing lights, and warning bell
A level crossing with road gates. Some level crossings, such as this one in Acton, Massachusetts, are also equipped with sidewalk gates.
A level crossing with road gates. Some level crossings, such as this one in Acton, Massachusetts, are also equipped with sidewalk gates.
Railroad Crossing in Montana, USA
Railroad Crossing in Montana, USA
A traditional mechanical crossing bell. Newer crossings have electronic bells that produce a clearer warning sound.
A traditional mechanical crossing bell. Newer crossings have electronic bells that produce a clearer warning sound.
A traditional electronic crossing bell made by General Signals Inc.
A traditional electronic crossing bell made by General Signals Inc.

In the United States and in countries following U.S. practices, a locomotive must have a bright headlight and ditch lights (short-throw bright lights located below the headlight), a working bell, and a whistle or horn that must be sounded four times (long-long-short-long, or the letter Q in Morse code) as the train approaches the crossing.

Some American cities, in the interest of noise abatement, have passed laws prohibiting the sounding of bells and whistles; however, their ability to enforce such rules is debatable. In December 2003, the U.S. Federal Railroad Administration published regulations that would create areas where train horns could be silenced, provided that certain safety measures were put in place, such as concrete barriers preventing drivers from circumventing the gates or automatic directional whistles (also called wayside horns) mounted at the crossing (which reduce noise pollution to nearby neighborhoods). Additional information can be found at the FRA website under "Train horn rule." Implementation of the new "Quiet Zone" Final Rule was delayed repeatedly but was finally implemented in the summer of 2005. Rail "Quiet Zone" crossings still require bells as part of the AWDs in addition to the wayside horns.

All crossings in the United States are required to be marked by at least a crossbuck; most crossings that intersect rural roads have this setup. In the event that the crossing contains more than one railroad track the crossbuck will usually have a small sign below denoting the number of tracks at the crossing. As traffic on the road crossing or the rail crossing increases, safety features are increased accordingly. More heavily trafficked crossings have automatic warning devices (AWDs), which feature alternately flashing red lights to warn automobile drivers and a bell to warn pedestrians. Additional safety is attained through crossing gates that block automobiles' approach to the tracks when activated. Increasingly, crossings are being fitted with four-quadrant gates to prevent circumventing the gates and crossing the tracks.

Operation of a typical AWD-equipped railroad crossing in the United States is as follows:

  • Approximately 30 seconds before arriving at the crossing, the train trips a track circuit near the crossing, triggering the crossing signals. The lights begin to flash alternately, and a bell mounted at the crossing begins ringing. After several seconds of flashing lights and ringing bells, the crossing gates (if equipped) begin to lower, which usually takes 5-10 seconds. Some AWDs will silence the bell once the gates are fully lowered; most continue ringing the bells throughout. The lights continue to flash throughout regardless.
  • Approximately 15 to 20 seconds before arriving at the crossing, the train begins ringing its engine bell and sounds its horn in accordance with NORAC rule 14L or GCOR rule 5.8.2(7): two long blows, one short blow, and one long blow. This signal and engine bell ringing is prolonged or repeated until the engine occupies the crossing. If the AWD is equipped with a directional horn in accordance with FRA Quiet Zone rules, the AWD may provide the whistle signal instead of the train; however, the engine is required to ring its bell regardless.
  • After the train has cleared the crossing, the gates (if equipped) begin to rise, and the bells (if silenced) may begin ringing again. Once the gates have completely risen back to their fully raised position, all warning signals, including the lights and bells, are deactivated.

Some AWD track circuits are equipped with motion detectors that will deactivate the crossing signal if the train stops or slows significantly before arriving at the crossing.

As indicated above, the pattern of the bells at each individual crossing can be different. (These bells should not be confused with the bells that are mounted on the trains themselves.) Generally, the bells follow one of these patterns:

  • The bell begins ringing when the lights begin flashing and ringing ceases when the gates have completely lowered.
  • The bell begins ringing when the lights begin flashing and ringing ceases when the gates begin to go up (following the passing of the train.)
  • The bell begins ringing when the lights begin flashing and ringing temporarily stops when the gates have completely lowered. However, when the gates begin to rise, the bell begins ringing again, and rings until the gates have returned to their original position.
  • The final, and most common, practice is for the bells to begin ringing when the lights begin flashing, keep ringing after the gates have completely lowered, and continue ringing while the gates are rising, only to cease when they have risen completely back to their original position.

A handful of level crossings still use wigwag signals, which were developed in the early 1900s by the Pacific Electric Railway interurban system in the Los Angeles region to protect its many level crossings. Though now considered to be antique, around 100 such signals are still in use, almost all on branch lines. By law, these signals must be replaced by the now-standard alternating red lights when they are retired.

A special kind of crossing sign assembly was introduced on an experimental basis in Ohio in 1992, the "Buckeye Crossbuck". It includes an enhanced crossbuck, reflective and with red lettering, and also a reflective plate reading "YIELD" below the crossbuck, whose sides are bent backwards in order to catch and reflect at a right angle the light of an approaching train. The experiment's final report ("Evaluation of the Buckeye Crossbuck at Public, Passive Railroad/Highway Grade Crossings in Ohio", Ohio Department of Transportation State Job Number 14612, December 2000) gave the device a favorable review.[6] However, the plate was rejected for inclusion in the 2003 Manual on Uniform Traffic Control Devices.[7]

A track that will run high-speed trains in excess of 120 mph (193 km/h) is being tested in Illinois between Chicago and St. Louis, Missouri. Here, due to the high speed of the trains, gates that totally prevent road traffic from reaching the tracks are mandatory on all level crossings. Steel mesh nets were tested on some crossings to further prevent collisions, but these were removed because of maintenance issues in 2001.

A new device called "StopGate" has been installed at four locations, one in Madison, Wisconsin; another in Monroe, Wisconsin and two in Santa Clara, California (on a light rail system)[citation needed]. This system resembles a fortified version of a standard crossing gate, with two larger arms blocking the entire width of the roadway and locking into a securing device on the side of the road opposite the gate pivot mechanism. The gate arms are reinforced with high-strength steel cable, which helps the gate absorb the impact of a vehicle attempting to crash through the gate. The manufacturer claims that the StopGate can arrest a 2,000 kg (4,400 lb) truck within 13 feet (four meters)[citation needed]. Already the system has been tested at the Madison crossing, when the system stopped a truck while a Wisconsin and Southern Railroad train was in the crossing.[citation needed]

Another new type of barrier is being tested in Michigan that is hoped will reduce the number of times drivers attempt to drive around lowered crossing gates. The new devices are called "delineators" consisting of a series of flexible cylinders that raise vertically out of vertical tubes in the pavement when the crossing signal is activated. The delineators are designed so that they will not be broken and will not damage vehicles if they are hit, allowing vehicles to exit the level crossing if they are already within it when the gates are activated. The test period for the new barrier began on December 5, 2007, and will run for a period of 17 months.[8][9]

[edit] Gallery


[edit] Major accidents

[edit] See also

[edit] References

  1. ^ Rivanna Chapter, National Railway Historical Society (2005). This Month in Railroad History: August. Retrieved on 2006-08-25.
  2. ^ Statistics of level crossings, Taiwan Railway Administration, 2002 (Chinese)
  3. ^ Statistics of level crossings, Taiwan Railway Administration, 2005 (Chinese)
  4. ^ Level crossing emergency button, Taiwan Railway Administration, (Chinese)
  5. ^ BBC report on Ufton Nervet rail crash
  6. ^ Russ College of Engineering and Technology (December 2000). Evaluation of the Buckeye Crossbuck at Public, Passive Railroad/Highway Grade Crossings in Ohio (PDF). Ohio Department of Transportation. Retrieved on 2007-12-06.
  7. ^ Manual on Uniform Traffic Control Devices - Part 8: Traffic Controls for Highway-Rail Grade Crossings (PPT). United States Federal Highway Administration (2003). Retrieved on 2007-12-06.
  8. ^ Mulcahy, John. "Railroad barrier put to the test", Ann Arbor News, 2007-12-06. Retrieved on 2007-12-07. 
  9. ^ Helms, Matt. "Railroad crossing in Wayne Co. to test new technology", Detroit Free Press, 2007-12-06. Retrieved on 2007-12-07. 

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