HOV lanes are normally created to increase higher average vehicle occupancy and person throughput with the goal of reducing traffic congestion and air pollution.

Vehicles registered prior to July 2006 were exempted from occupancy requirements in all ( HOV ) facilities in Virginia until July 1, 2009.

As of 2010 High occupancy vehicle lane | HOV lanes exist on the co-signed QEW-403.

High occupancy vehicle lane | HOV lanes on the co-signed 403-QEW

Additional general purpose lanes and a high occupancy vehicle lane ( HOV ) are being constructed along the eastern stretch of Loop 101 from Scottsdale to Chandler, starting at Princess Drive to Loop 202, Santan Freeway.

However, they are divided up into general use / frontage roads / HOV lanes, restricting the traverse traffic flow.

A high-occupancy vehicle lane ( also HOV lane, carpool lane, diamond lane, and transit lane or T2 or T3 lanes in Australia and New Zealand ) is a restricted traffic lane reserved at peak travel times or longer for exclusive use of vehicles with a driver and one or more passengers, including carpools, vanpools and transit buses.

Motorcycles are permitted in the HOV lanes for safety reasons.

The introduction of HOV lanes in the U. S. progressed slowly during the 1970s and early 1980s.

As of 2005, the two lanes of this HOV 3 + facility were carrying during the morning peak hour ( 6: 30 am to 9: 30 am ) a total of 31, 700 people in 8, 600 vehicles ( 3. 7 persons / veh ) while the 3 or 4 general purpose lanes carried 23, 500 people in 21, 300 vehicles ( 1. 1 persons / veh ).

Average travel time in the HOV facility is 29 min while 64 min in the general traffic lanes.

As of 2012, the I-95 / I395 HOV facility is long and extends from Washington, D. C. to Dumfries, Virginia, has two reversible lanes separated from the regular lanes by barriers, with access through on and off elevated ramps.

As of 2012 the Interstate 95 in Virginia | I-95 / Interstate 395 ( District of Columbia – Virginia ) | I-395 HOV facility operates as a two-lane barrier-separated reversible lane | reversible HOV 3 + facility ( center lanes ) with access through elevated on-and off-ramps.

In the 1970s the FHWA began to allow state highway agencies to spend federal funds on HOV lanes.

As a result of the 1973 Arab Oil Embargo, interest in ridesharing picked up and the states began experimenting with HOV lanes.

However, it took until 1985 before any HOV project was constructed in Los Angeles County, and by 1993 there were only of HOV lanes countywide.

" Express bus transportation and an interstate with HOV lanes that ends five miles south of Huntersville provide access to the downtown business areas of Charlotte, making Huntersville primarily a town of commuters.

** HOV lanes, for vehicles with at least three ( sometimes at least two ) riders, intended to encourage carpooling

This marking is most often used to denote high-occupancy vehicle lanes or bus lanes, with accompanying signage reading "◊ HOV LANE " or "◊ BUS LANE " and giving the requirements for a vehicle to be accepted.

The corridor may be in addition to GRTA Xpress or even CCT buses on the parallel Interstate 575, which is scheduled to get new HOV lanes soon.

All 400-series highways should have at least two lanes in each direction, with HOV lanes separated from general traffic with a striped buffer zone and full shoulder if necessary.

In addition, 400-metre or longer " weave lanes " are required for transitions to / from HOV lanes across the buffer zones to allow for safe mergers.

Slugging lines are common in some places, where solo drivers pick up a passenger to share the ride and allow use of the HOV lane.

Three or more people in a vehicle ( HOV 3 +) are required to travel on the facility during rush hours on weekdays.

The HOV lanes run between Downtown Houston ( inbound A. M. and outbound P. M .) and the suburbs and are found on portions of the Katy Freeway, Gulf Freeway, North Freeway, Southwest Freeway, Eastex Freeway, and Northwest Freeway.

In an effort to reduce traffic and encourage carpooling some countries have introduced high-occupancy vehicle ( HOV ) lanes in which only vehicles with two or more passengers are allowed to drive.

However, HOV lanes which are additional to existing capacity do result in an induced rise in overall traffic, because the shift of HOVs to the new lane releases capacity in the existing lanes, reducing the generalised cost of journeys in those lanes and thus increasing demand.

Motorcycles and " clean fuel " vehicles ( hybrid and compressed natural gas ) are exempt from HOV restrictions in Virginia, allowing single-passenger vehicles of those types to use the lanes as well.

There are HOV lanes in operation 24 hours a day in each direction of SR-170 between I-5 and the Hollywood Split interchange.

While there are no such current plans, the design of the bridge allows for rail or other mass transit to replace the HOV / bus lanes in the future.

Where HOV lanes are present for carpooling, the ramps of a diamond interchange may be folded to the inside lanes instead of the outside.

HOV lanes are not usually considered hammer lanes, but are also used for express travel by commuters.

Currently, Sound Transit and the Washington State Department of Transportation are relocating HOV lanes from the reversible express lanes to the eastbound and westbound lanes of Interstate 90.

Motorcycles, alternative fuel cars, hybrids registered in Virginia before July 1, 2006, and federal law enforcement vehicles are also permitted to use HOV lanes, even if carrying only one occupant.

There are currently 52 lane-miles of roadways and ramps, with four freeway junctions and numerous local ramps, and with several interchanges to the reversible express ( HOV ) roadway, all within a section of the Shirley Highway.

There are no HOV lanes currently, but the medians have been designed with sufficient clearance for their construction should the need arise in the future.

Many improvements are slated for I-270, including the construction of three new interchanges and the widening of the route between Shady Grove Road and Frederick that would add HOV and express toll lanes.

The new lanes, and frustration over failures of public-transport systems and high fuel prices, led to the creation in the 1970s of " slugging ", a form of hitchhiking between strangers that is beneficial to both parties, as drivers and passengers are able to use the HOV lane for a quicker trip.

While passengers are able to travel for free, or cheaper than via other modes of travel, and HOV drivers sometimes pay no tolls, " slugs are, above all, motivated by time saved, not money pocketed ".

Concern for the environment is not their primary motivation ; Virginia drivers of hybrid automobiles are, for example, eligible to use HOV lanes with no passenger.

Double lines indicate that lane-changing ( for example to overtake ) is prohibited, such as in tunnels or sometimes for HOV lanes and HOT lanes.

For example, part of the southbound HOV lane on I-5 between Seattle and Tacoma is a contraflow lane on what is otherwise the northbound side of the highway.