Level of Service (LOS)

What is Level of Service (LOS) ?

Level of Service is a part and frequently used term and concept of transportation planning in urban planning. A transport planner finds it useful for number of surveys. It helps in planning for existing and upcoming projects.

Capacity standards are fixed normally in relation to the Level Of Service (LOS) adopted for the design. Level of Service is a part and frequently used term and concept of town planning. A transport planner finds it useful for number of surveys. is defined as a qualitative measure describing operational conditions within a traffic stream, and their perception by drivers/passengers.

LOS generally describes these conditions in terms of factors such as speed and travel time, freedom to maneuver, traffic interruptions, comfort, convenience and safety. Six levels of service are recognized commonly, designated from A to F, with Level of Service is a part and frequently used term and concept of town planning. A transport planner finds it useful for number of surveys. A representing the best operating condition i.e. free flow and Level of Service is a part and frequently used term and concept of town planning. A transport planner finds it useful for number of surveys. F the worst i.e. forced or break-down flow. On urban roads, the LOS is affected strongly by factors like the heterogeneity of traffic, speed regulations, frequency of intersections, presence of bus stops, on-street parking, roadside commercial activities, pedestrian volumes etc.

Level of Service is a qualitative measure used to symbolize the quality of traffic services. It is used to examine highways by categorizing traffic flow and allocating quality levels based on performances like speed, density, delay and many more.

  • This term is used for the transportation engineering field. Engineers evaluated the system of transport on quality based on different factors including roadways in peak period traffic volume.
  • There is a grading system which involves A to F to just like there is grade provided in elementary school that indicates roadway capacity in a better way.
  • There is a different flow of traffic on different days and different time too.
  • With List of Service, there would traffic service quality on a particular flow rate of traffic.
  • Different operating conditions are depended on the type of facility. Highway capacity manual is the research board of the USA that comes with some procedure to understand the level of service.

Level of Service | Transportation

Quality of traffic range in size different levels from A to F

  1. A is considered as the best quality of traffic where the driver can enjoy his drive with better flow and speed of their own choice. While level F stands for worst quality of traffic. A stands for free flow where the motorist has the ability to move between the lanes. There is a high level of physical and psychological comfort to the drivers.
  2. B stands for reasonable free flow where the speed of vehicles is maintained, flexibility for moving between the lanes within the traffic is slightly limited. There is a high level of physical and psychological comfort to the drivers.
  3. C stands for stable flow or near free flow. The mobility of changing lanes require drivers attention and is noticeably limited compared to other. Experienced drivers are comfortable. The minor occurrence may not have a great effect but service will show noticeable effects and there is a chance of traffic delays.
  4. D signifies proceed towards the unstable flow. Speed decreases as the number of vehicles slightly increase. Freedom for changing the lanes within the traffic stream is quite limited and the drivers level of comfort decreases. Minor occurrence on the roads can create delays for the others. This is usually found common on urban streets during the time of peak hours.
  5. E is unstable Flow because of the lesser or unusable gaps, the flow becomes irregular and the speed can increase or decrease. The traffic rarely reaches to its appropriate limit or suggested limit. Speed is nearby or above 50 ml/h. Shockwave is created when there is change is lane or merging of traffic. Any accidents may cause a noticeable delay. Level of comfortability in this flow becomes poor for the driver. In urban areas usually, we face this problem because of the road congestion which cannot be changed.
  6. F leads to a breakdown of the flow. The time for traveling is not predicted, usually, it takes more than its capacity. A Highway may face Level of Service D during its busy hours with C some days and F at other days or once in a week.

This considerably affects transportation and decisions of urban planning and overall it implies on our lives. The results are usually unconditional they indicate positive ways for wider roads with speeds of higher designs. Although, this degrades the condition like walking and cycling of people, that creates a barrier.

Factors affect the level of service

  • Speed and travel time
  • Traffic restrictions
  • Freedom to travel with the desired speed
  • Driver comfort and convenience
  • Operating Cost
  • One of the factors that are kept in consideration for service quality is the amount of time taken for traveling. Therefore, speed and traveling time are considered as important factors to upgrade or degrade the Level of service.
  • The classification of transportation facilities is depended on two factors, Uninterrupted flow and interrupted flow due to which Level of service is effected.
  • A flow of traffic where there is no obstruction of vehicles is known as Uninterrupted flow, a freeway is one of its examples. A vehicle does not stop anywhere till the freeway is finished. There are multi-lanes provided for the uninterrupted traffic flow. Interrupted flow is a condition where there is an obstruction on the way of a road due to some or other reasons. Bus transit where they have to stop at multiple bays that share a road with other vehicles are involved in an Interrupted flow.
  • The system of Level of Service was initiated for the development of highways for expanding its use and availability of private cars. The basic factor that involves was congestion. There are some professors who considered public transportation as an important factor for a delay.
  • There should be measurements of the level of service took for that transportation into account. As public transportation involves wait time, the frequency of service, quality of ride, accessibility, fares, and many other criteria. Level of service can be implied on surface streets.
  • Urban areas usually adapt C and E level of service and F in areas where pedestrian walking, bicycle or transits alternatives are present.

Bottom line

The level of service has helped in determining various factors that can help us in deciding well that what can be the possible causes of the accidents. Also, it has helped us recognize those highways which are deadly. It helps to fight the problem of congestion and the hazards it can lead to.

A to F levels of service govern the various road conditions and also indicate where all amendments are required. It is a mark of recognition about where we are required to process with the work in order to get good quality of hassle free traffic. Then, only road calamities be lessened. We hope that the above informative article will surely help you realize well the importance of studying public transport and how it can be modified in a better way. Stay tuned for more such interesting updates. Be safe and drive carefully.