Lane control lights

rdf:langString Lane control lights

rdf:langString 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 (to permit) or by red lights or crosses (to prohibit). When used, they are usually repeated at regular distances to provide a continuous reminder of the lane status to drivers. On certain multiple-lane highways, one or more lanes may be designated as counterflow lanes, meaning that the direction of traffic in those lanes can be reversed at any time (see also reversible lane). Sometimes this is done as a way of managing rush hour traffic (one or more central lanes may flow inbound in the morning and outbound in the evening); in other cases the lanes are reversed only in unusual circumstances (such as a traffic accident or road construction closing one or more of the lanes). Lane control signals around the world follow their own universal pattern, as specified in the Vienna Convention on Road Signs and Signals. Typical signals include a green downward arrow, used to indicate a lane which is open to traffic facing the signal, a red cross, which indicates a lane is either reserved for opposing traffic or closed to traffic in both directions, and a flashing amber circle, arrow or cross, indicating to traffic facing the signal to immediately clear the lane. Unlike regular traffic lights, lane control signals either have one face each to indicate all lane conditions (the so-called "searchlight" configuration), or separate faces for each condition (as illustrated). Lane control signals of the latter type are usually placed horizontally. Signals that may indicate other conditions for roads without counterflow lanes also exist, such as those that indicate different speed limits for different lanes.