§ 2.5. Level of Service Standards

Level of service, as used in transportation planning and engineering, is a qualitative measure describing operational conditions within a traffic stream and their perception by motorists. The qualitative descriptions are equated to quantitative measures for the purposes of planning and engineering analyses. Factors which affect the qualitative measures include vehicle density, average travel speed, volume to capacity ratio, average stopped delay, etc.

Level of Service A:	Level of Service B :
-Uninterrupted flow	-Stable flow conditions
-No restriction on maneuverability	-Operating speed begins to be restricted
-Little or no delay
Level of Service C:	Level of Service D:
-Speed and maneuverability restricted by higher traffic volumes	-Low speeds
-Satisfactory operating speed for urban conditions	-Major delays at signals
-Delay at signals	-Little freedom to maneuver
Level of Service E:	Level of Service F
-Lower operating speeds	-Low speeds
-Volumes at or near capacity	-Stoppages for long periods because of downstream congestion
-Major delays and stoppages