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/3, e o owing c cx{ anal a t e eve -o -se ce c eept u nt. of the bans for the comparisons made to the analysts. "Level-of-service" is a term denotes any of a number of cumbinaliuna of traffic operating conditioru that may oc a given roadway when it is subject to various traffic volumes. Factors such as speed, time, traffic interruptions, freedom to maneuver, safety, driving comfort and conve affect the determination of level-of-aervtce. Analytically, it is related to a ratio of the ' volume to the theoretical traffic capacity of the roadway or intersection (V/C ratio, _ There are six levels-of-service, A through F, which describe driving condittons from beat to worst, respectively. They are described as follows: _ • I.avel-of•aervice A represents uncongested, free-tfow conditions. On a two- _ _ lane road, passing demand is well below passing capacity. Drivers would be delayed no more than 30 percem o~tne time by dow moving vehicles. For multi-lane highways, the abdrty to maneuver within the traffic stream is high. . Minor traffic flow disruptions at thin level are easily absorbed without causing significant delays or queuing. • Lerel-o[ service B is indicative of a stable flow where the presence of other vehicles begins to be noticeable. As passing demand approaches capacrry on two-lane roadways, platooning is common. At this level, minor traffic disruptions are still easily absorbed, but local deterioration in LOS will be more obvious. , • Lerel-ofservice C represents conditions at which noticeable delays occur and the Freedom to maneuver between lanes becomes restricted. Slowing of trafFic is particularly noticeable when vehicles turn jell and passing capacity is reduced. • level-of-service D represents congestion and the limits of stable traffic flow. Traffic congestion severely restricts speeds :loci the :tbiliry to maneuver. Only the most minor of traffic disruptions can occur without extensive queues forming. On two-lane roads, passing demand is iugh while passing capacity approaches zero. • I.evet-ot•setvice E represents unstable traffic flow operations at or near capacity. Any disruption, no matter how minor, causes queues and deterioration of LOS. Passing becomes virtually impossible on two-lane roadways. • Level•of-service F represents heavily congested flow with the traffic demand exceeding apaciry. Operation within queues are very unstable, with traffic experiencing short spurts of movement followed by stoppages.