Lane
Encyclopedia
A lane is a part of the roadway
Carriageway
A carriageway consists of a width of road on which a vehicle is not restricted by any physical barriers or separation to move laterally...

 (British: carriageway) within a road
Road
A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...

 marked out for use by a single line of vehicles in such a way as to control and guide drivers for the purpose of reducing traffic conflicts. Most public roads (highways) have at least two lanes, one for traffic in each direction, separated by Lane markings. Major highways often have two roadways separated by a median
Central reservation
On divided roads, such as divided highways or freeways/motorways, the central reservation , median, parkway , median strip or central nature strip is the area which separates opposing lanes of traffic...

, each with multiple lanes. A single-track road carries traffic in both directions within a single lane with passing places to allow vehicles to pass. In North America and Australia, the term also may refer to rear access roads which act as a secondary vehicular network in cities and towns. A minor rural road may be referred to as a country lane
Country lane
A country lane is a narrow road in the countryside.In North America and Australia, the term also may refer to rear access roads which act as a secondary vehicular network in cities and towns. Large cities in the US states of Nevada and Texas tend to apply the term to many arterial roads...

; some urban streets which began as country lanes are still called lanes, such as Drury Lane
Drury Lane
Drury Lane is a street on the eastern boundary of the Covent Garden area of London, running between Aldwych and High Holborn. The northern part is in the borough of Camden and the southern part in the City of Westminster....

 in London.

Types of lanes

  • A traffic lane or travel lane is a lane for the movement of vehicles traveling from one destination to another, not including shoulders
    Shoulder (road)
    A hard shoulder, or simply shoulder, is a reserved area by the verge of a road or motorway. Generally it is kept clear of motor vehicle traffic...

     and auxiliary lanes.
  • A through lane or thru lane is a traffic lane for through traffic. At intersections, these may be indicated by arrows on the pavement pointing straight ahead.
  • A carriageway
    Carriageway
    A carriageway consists of a width of road on which a vehicle is not restricted by any physical barriers or separation to move laterally...

    (Great Britain), roadway (United States) is a group of two or more lanes on a single paved surface. A rural 2-lane highway is usually built on a single surface with traffic in both directions, while large highways can be built with two (sometimes more) of these separated by buffers such as medians and barriers. On such highways, the lanes in each group usually travel in the same direction.
  • A deceleration lane is a paved or semi-paved lane adjacent to the primary road or street. It is used to improve traffic safety by allowing drivers to pull off the main road and decelerate safely in order to turn (e.g. right in the United States or left in Great Britain), so that the traffic behind the turning vehicle is not slowed or halted. Deceleration lanes are primarily found in suburban settings.
  • A fire lane
    Fire lane
    A fire lane is a marked lane in a parking lot that is near a structure. Parking is prohibited in fire lanes to ensure the access of safety equipment to the structure in the event of an emergency....

    is the area next to a curb
    Curb (road)
    A curb, or kerb , is the edge where a raised pavement/sidewalk/footpath, road median, or road shoulder meets an unraised street or other roadway.-Function:...

    , which is reserved for firefighting equipment, ambulance
    Ambulance
    An ambulance is a vehicle for transportation of sick or injured people to, from or between places of treatment for an illness or injury, and in some instances will also provide out of hospital medical care to the patient...

    s, or other emergency vehicles. Parking in these areas, often marked by red lines, usually warrants a parking ticket.
  • A loading lane (loading zone in the United States) is an area next to a curb, which is reserved for loading and unloading passengers and/or freight. It may be marked by a sign ("LOADING ONLY" or "LOADING ZONE") or by a yellow or white-painted curb.
  • A passing lane
    Passing lane
    A passing lane or overtaking lane is the lane on a multi-lane highway or motorway closest to the center of the road ....

    is often provided on steep mountain grades, in order to allow smaller vehicles to pass larger, slower ones. This is sometimes called a climbing lane if on the uphill side. (See truck lane below). Passing lanes may also be provided on long stretches of other roadway. On two-lane roads, using the lane of oncoming traffic as a passing lane is sometimes allowed given a long enough straightaway. In many countries permission is indicated by a broken line on the same side of the centerline as the vehicle intending to pass.
  • A collector lane of a road is used for slower moving traffic and has more access to exits/off ramps.
  • An express lane of a road is used for faster moving traffic and has less access to exits/off ramps. In other areas, an express lane may refer to a HOV lane (see below).
  • A transfer lane of a road is used to move from express lanes to collector lanes, or vice-versa; it is somewhat similar to an auxiliary lane.
  • A merge lane is a lane or onramp used to merge two flows of traffic into one, with the merge lane being the lane that disappears at the end of the merging area. Merge lane lengths depend mainly on the speed differential of the two merging flows, as the slower flow has to use the lane to accelerate.
  • An auxiliary lane along a highway
    Highway
    A highway is any public road. In American English, the term is common and almost always designates major roads. In British English, the term designates any road open to the public. Any interconnected set of highways can be variously referred to as a "highway system", a "highway network", or a...

     or motorway connects slip roads, with the entrance ramp
    Inclined plane
    The inclined plane is one of the original six simple machines; as the name suggests, it is a flat surface whose endpoints are at different heights. By moving an object up an inclined plane rather than completely vertical, the amount of force required is reduced, at the expense of increasing the...

     or acceleration lane from one interchange
    Interchange (road)
    In the field of road transport, an interchange is a road junction that typically uses grade separation, and one or more ramps, to permit traffic on at least one highway to pass through the junction without directly crossing any other traffic stream. It differs from a standard intersection, at which...

     leading to the exit ramp or deceleration lane of the next.
  • The emergency lane of a road (also known as the breakdown lane, shoulder or hard shoulder) is reserved for breakdowns
    Breakdown (vehicle)
    A vehicle breakdown is the operational failure of a motor vehicle in such a way that the underlying problem prevents the vehicle from being operated at all, or impedes the vehicle's operation so much, that it is very difficult or nearly impossible, or dangerous to operate, or else at risk of...

    , and for emergency vehicle
    Emergency vehicle
    An emergency vehicle is any vehicle that is designated and authorized to respond to an emergency. These vehicles are usually operated by designated agencies, often part of the government, but also run by charities, non-governmental organizations and some commercial companies...

    s. The inner boundary of the lane often features rumble strips
    Rumble Strips
    Rumble Strips may refer to:* Rumble strip, the road safety feature* The Rumble Strips, the British band...

     in order to physically warn drowsy or inattentive drivers that they are drifting off the roadway. This feature is seen especially often on highways and motorways, where the minimally-stimulating and monotonous nature of high-speed driving at night increases the chances for driver disorientation and serious injury or death if an accident does take place.
  • An HOV lane or carpool lane is reserved for carpool
    Carpool
    Carpooling , is the sharing of car journeys so that more than one person travels in a car....

    ing. In the US, they may be marked with a diamond icon every few hundred feet (hence the nickname "diamond lane
    Diamond lane
    A diamond lane is a special lane on a street or highway that is reserved for specific types of traffic. These lanes are usually marked with white diamonds, hence their name. Diamond lanes are generally the right-most or left-most lane on the road...

    "), or separated from other lanes by double broken white lines, a continuous pair of double yellow lines, or just a single broken white line.
  • A High-occupancy toll lane is a combination of an HOV lane and toll collection technology that allows drivers without passengers to use the HOV lane by paying a premium price for the privilege
  • A turn lane is set aside for slowing down and making a turn, so as not to disrupt traffic. At a full intersection
    Intersection (road)
    An intersection is a road junction where two or more roads either meet or cross at grade . An intersection may be 3-way - a T junction or fork, 4-way - a crossroads, or 5-way or more...

     with a traffic light
    Traffic light
    Traffic lights, which may also be known as stoplights, traffic lamps, traffic signals, signal lights, robots or semaphore, are signalling devices positioned at road intersections, pedestrian crossings and other locations to control competing flows of traffic...

    , turn lanes are used more to hold traffic until the light changes.
  • A designated bicycle lane is a portion of the roadway or shoulder designated for the exclusive or preferential use of bicyclists. This designation is indicated by special word and/or symbol markings on the pavement and "BIKE LANE" signs.
  • A motorcycle lane
    Motorcycle lane
    Motorcycle lane is a main term for special lane for small vehicles such as motorcycles, scooters, bicycles, trishaw and many more.- Malaysia :...

    is provided at certain roads and highways such as the Federal Highway
    Federal Highway, Malaysia
    Federal Highway, or Lebuhraya Persekutuan in Malay is a Malaysian highway connecting the capital city of Kuala Lumpur, and Klang, Selangor. The highway starts from Seputeh in Kuala Lumpur to Klang, Selangor...

     in Malaysia to segregate the motorcycle traffic from the main roadways to reduce motorcycle-related accidents. The motorcycle lane may form a part of the hard shoulder, or may be built as completely separated lanes.
  • A bus lane
    Bus lane
    A bus lane or bus only lane is a lane restricted to buses, and generally used to speed up public transport that would be otherwise held up by traffic congestion...

    is reserved for buses providing public transportation on a fixed route, sometimes with overhead catenary
    Overhead lines
    Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains at a distance from the energy supply point...

     for trolleybus
    Trolleybus
    A trolleybus is an electric bus that draws its electricity from overhead wires using spring-loaded trolley poles. Two wires and poles are required to complete the electrical circuit...

    es. In some countries, bus lanes may also be used by some other traffic, such as taxis, bicycles and motorbikes.
  • A reversible lane
    Reversible lane
    A reversible lane , called a counterflow lane or contraflow lane in transport engineering nomenclature, is a lane in which traffic may travel in either direction, depending on certain conditions...

    (contraflow lane
    Contraflow lane reversal
    Contraflow lane reversal refers to plans that alter the normal flow of traffic, typically on a controlled-access highway , to either aid in an emergency evacuation or, as part of routine maintenance activities, to facilitate widening or reconstruction of one of the highway's carriageways...

     in Hawaii
    Hawaii
    Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

    ) uses overhead lane light markers
    Lane control lights
    Lane control lights are a specific type of traffic light used to manage traffic on a multi-way road or highway. Typically they allow or forbid traffic to use one or more of the available lanes by the use of Green lights or arrows or by red lights or crosses...

    , signs, poles or barriers to indicate the current direction of travel. They are used to accommodate periods of high traffic flow, especially rush hour
    Rush hour
    A rush hour or peak hour is a part of the day during which traffic congestion on roads and crowding on public transport is at its highest. Normally, this happens twice a day—once in the morning and once in the evening, the times during when the most people commute...

     where the flow is predominantly in one direction, on roads that cannot be easily widened. One or more lanes are removed from the opposing flow and added to the peak flow. Outside peak hours, the lanes revert to their normal configuration, perhaps with a center turn lane. To reduce the chance of head-on accidents, a resting period of an hour is often employed when reversing a lane; no traffic is allowed in the lane during this time. Some roads use portable barriers or plastic poles that are manually rearranged by work crews before and after the peak period, others use both lights and on-street markings (broken double-yellow line) or overhead lights. In some areas, the term suicide lane became a common slang description for this design because many people ignore the traffic control devices. Because of their history of numerous accidents and collisions, reversible lanes are rarely used.
  • A tram lane is a lane reserved for the use of buses, trams and taxicabs. It is usually encountered in cities with curbside tram network, such as Zagreb
    Zagreb
    Zagreb is the capital and the largest city of the Republic of Croatia. It is in the northwest of the country, along the Sava river, at the southern slopes of the Medvednica mountain. Zagreb lies at an elevation of approximately above sea level. According to the last official census, Zagreb's city...

    .
  • A truck lane (United States) or crawler lane (Great Britain) is a lane provided on long and steep uphill stretches of high-speed roads to enhance the ability of vehicles which can maintain speed up the incline to pass those vehicles (usually heavy trucks) which cannot. In addition, these lanes are intended to optimize pavement performance and minimize pavement fatigue. The lane is marked only on the uphill stretch and usually a short distance afterward (for regaining speed). A truckway often allows longer box length; for instance, the Florida Turnpike allows 29.3 meter double trailer combinations, in contrast to normal Florida highways' 16.2 meter limit. Since the major cost of trucking is the fixed cost of the same trailer with its driver the cost per ton of operating with truckway size and weight allowances is 35 to 40 percent below the cost of operations on the non-truckways.
  • An operational lane or auxiliary lane is an extra lane on the entire length of highway between interchanges, giving drivers more time to merge in or out. The lane is created when an entrance ramp meets the highway, and drops out (with an "exit only" sign) to become the ramp at the next exit.
  • An overtaking lane is the lane furthest from the shoulder of a multi-lane carriageway/roadway (sometimes called the fast lane, although this is deprecated by the authorities).
  • The slow lane is the lane nearest to the shoulder of a multi-lane carriageway/roadway. This usage leads to the phrase Life in the Slow Lane, used as the title of various books and songs.
  • A driving lane is an area in a parking lot
    Parking lot
    A parking lot , also known as car lot, is a cleared area that is intended for parking vehicles. Usually, the term refers to a dedicated area that has been provided with a durable or semi-durable surface....

    /car park in between parking space
    Parking space
    A parking space is a location that is designated for parking, either paved or unpaved.Parking spaces can be in a parking garage, in a parking lot or on a city street. It is usually designated by a white-paint-on-tar rectangle indicated by three lines at the top, left and right of the designated area...

    s so that vehicles can drive into and out of the spaces.
  • A farm lane, which typically is the private property of one or more landowners, provides access to rural dwellings and agricultural buildings. It may be paved with concrete, asphalt, tar macadam, water bound macadam, gravel, or nothing more than earth, compressed with use.
  • The term country lane, by contrast, typically denotes a public rural road. Farm lanes connect properties to country lanes (or to main roads).

Lane width and capacity

The U.S. Interstate Highway System
Interstate Highway System
The Dwight D. Eisenhower National System of Interstate and Defense Highways, , is a network of limited-access roads including freeways, highways, and expressways forming part of the National Highway System of the United States of America...

 uses a 12 feet (3.7 m) standard for lane width. 11 feet (3.4 m) lanes are found to be acceptable by the Federal Highway Administration
Federal Highway Administration
The Federal Highway Administration is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two "programs," the Federal-aid Highway Program and the Federal Lands Highway Program...

 for automobile traffic, but as lane width decreases (9 feet (2.7 m) lanes are found in some areas) traffic capacity decreases. A full-width freeway lane typically has a capacity of 2,000 cars per hour.

In the United Kingdom, many lanes are found in the countryside, and most of these lanes are wide enough for one car at a time and often have a lay by for cars to pass. In general, European laws and road width vary per country, with the minimum widths of lanes being anywhere between 2.5 m to 3.25 m (thus comparable to US lanes).

Lane markings

Painted lane markings vary widely from country to country. In the United States, Canada and Norway, yellow lines separate traffic going opposite directions and white separates lanes of traffic traveling the same direction, but this is not the case in many European countries.

Medians or central reservations

Besides a painted line, lanes of traffic moving in opposing directions can also be separated by any of the following:
  • Grass strip or ditch
  • A central turning lane that allows vehicles to turn into driveways or streets on the opposite side of the road without stopping traffic
  • A wide paved area with special paint markings indicating that it should never be crossed
  • Metal guard rail (or guide rail) affixed to metal or wooden posts
  • Cable barriers
  • Concrete barriers such as Jersey barrier
    Jersey barrier
    A Jersey barrier or Jersey wall is a modular concrete barrier employed to separate lanes of traffic. It is designed to both minimize vehicle damage in cases of incidental contact while still preventing crossover in the case of head-on accidents....

    s


Such separations between opposing traffic are referred to as a median in American English
American English
American English is a set of dialects of the English language used mostly in the United States. Approximately two-thirds of the world's native speakers of English live in the United States....

 and as a central reservation
Central reservation
On divided roads, such as divided highways or freeways/motorways, the central reservation , median, parkway , median strip or central nature strip is the area which separates opposing lanes of traffic...

 in British English
British English
British English, or English , is the broad term used to distinguish the forms of the English language used in the United Kingdom from forms used elsewhere...

.

Numbering of freeway lanes in California

Traffic reports in California often refer to accidents being "in the number X lane." The California Department of Transportation (Caltrans) assigns the numbers from left to right. The far left passing lane is the number 1 lane. The number of the slow lane (closest to freeway onramps/offramps) depends on the total number of lanes, and could be anywhere from 2 to 6.

History

For much of human history, roads did not need lane markings because most people walked or rode horses at relatively slow speeds. Another reason for not using lane markings is that they are expensive to maintain.

When automobiles, trucks, and buses came into widespread use during the first two decades of the 20th century, head-on collision
Head-on collision
A head-on collision is one where the front ends of two ships, trains, planes or vehicles hit each other, as opposed to a side collision or rear-end collision.-Rail transport:...

s became more common.

Without the guidance provided by lane markings, drivers in the early days often erred in favor of keeping closer to the middle of the road, rather than risk going off-road into ditches or trees. This practice often left inadequate room for opposing traffic.

There are two people who have been credited with the invention of lane markings. In 1911, Edward N. Hines
Edward N. Hines
Edward N. Hines , was a member of the Wayne County, Michigan, Road Commission from 1906 to 1938. He is one of the most important innovators in road development....

, the chairman of the Road Commission of Wayne County, Michigan
Wayne County, Michigan
-History:Wayne County was one of the first counties formed when the Northwest Territory was organized. It was named for the American general "Mad Anthony" Wayne. It originally encompassed the entire area of the Lower Peninsula of Michigan, as well as small sections that are now part of northern...

 was trying to make roads safer. He supposedly came up with the idea of painting stripes to separate lanes of traffic after riding behind a milk truck that leaked milk onto the center of the road, leaving a stripe.

June McCarroll
June McCarroll
June Hill Robertson McCarroll was a nurse with the Southern Pacific Railroad in the early twentieth century who is credited by Caltrans with the simple but revolutionary idea of delineating highways with a painted line to separate lanes of traffic...

, a physician
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...

 in Indio
Indio, California
Indio is a city in Riverside County, California, United States, located in the Coachella Valley of Southern California's Colorado Desert region. It lies east of Palm Springs, east of Riverside, and east of Los Angeles. It is about north of Mexicali, Baja California on the U.S.-Mexican border...

 California started experimenting with painting lines on roads in 1917 after she was run off of a highway by a truck driver. In November 1924, after years of lobbying by Dr. McCarroll and her allies, California officially adopted a policy of painting lines on its highways. A portion of Interstate 10
Interstate 10
Interstate 10 is the fourth-longest Interstate Highway in the United States, after I-90, I-80, and I-40. It is the southernmost east–west, coast-to-coast Interstate Highway, although I-4 and I-8 are further south. It stretches from the Pacific Ocean at State Route 1 in Santa Monica,...

 near Indio has been named the Dr. June McCarroll Memorial Freeway in her honor.

By 1939, lane markings had become so popular that they were officially standardized throughout the United States, and they were soon copied worldwide.

See also

  • Lane departure warning system
    Lane departure warning system
    In road-transport terminology, a lane departure warning system is a mechanism designed to warn a driver when the vehicle begins to move out of its lane on freeways and arterial roads. These systems are designed to minimize accidents by addressing the main causes of collisions: driver error,...

  • Road surface marking
    Road surface marking
    Road surface marking is any kind of device or material that is used on a road surface in order to convey official information. They can also be applied in other facilities used by vehicles to mark parking spaces or designate areas for other uses....

  • Traffic directionality
  • Green lane (road)
  • Country lane
    Country lane
    A country lane is a narrow road in the countryside.In North America and Australia, the term also may refer to rear access roads which act as a secondary vehicular network in cities and towns. Large cities in the US states of Nevada and Texas tend to apply the term to many arterial roads...

  • Shoulder (road)
    Shoulder (road)
    A hard shoulder, or simply shoulder, is a reserved area by the verge of a road or motorway. Generally it is kept clear of motor vehicle traffic...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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