Road Network Operations
& Intelligent Transport Systems
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Safety of Vulnerable Road Users

Mobility is part of daily life. Anyone using the roads is at risk of injury or death in the event of a road accident. Some people are more at risk than others and are commonly referred to as Vulnerable Road Users (VRU). The term has been defined in different ways:

  • World Health Organisation in 2013 considered VRUs to be “pedestrians, cyclists, and motorcyclists”
  • US DOT’s National Strategy on Highway Safety has a more complex definition: “road users who are most at risk for serious injury or fatality when they are involved in a motor-vehicle-related collision. These include pedestrians of all ages, types and abilities, particularly older pedestrians and people with disabilities. VRU‘s also include bicyclists and motorcyclists. Older drivers may also be considered to fit into this same user group”
  • European Union’s ITS Directive refers to “non-motorised road users, such as pedestrians and cyclists as well as motor-cyclists and persons with disabilities or reduced mobility and orientation”

Transport policy makers and road authorities who are responsible for road safety strategies and policies at national and local level need to provide safe road infrastructure that integrates protection for vulnerable road users. ITS technologies can help through:

  • design engineering of the road infrastructure to reduce accident risk, manage the conflicting requirements of different road users at critical locations and to reduce the impacts of any incidents
  • developing applications that raise awareness of the existence and needs of vulnerable road users, encourage safe road user behaviour by all road users and promote the use of dedicated road safety facilities where provided

Vehicle manufacturers are also exploring vehicle protection systems for Vulnerable Road Users (VRUs). These are often based on forward looking cameras mounted on the vehicle, used in conjunction with other in-vehicle safety applications such as forward looking radars and Collision Warning. (See Warning & Control) Video: Inside Ford’s Pedestrian Detection System


Walking is an essential part of daily mobility (if only from a parked vehicle to reach the final destination). As traffic on the roads increases, the potential risk of vehicle-pedestrian collisions increases also. The World Health Organisation’s 2013 statistics show that 22% of traffic fatalities globally are pedestrians.

Vehicle speed is a key factor in pedestrian fatalities. The Australian Federal Office of Road Safety and the UK Department for Transport assessed the relationship between the two. The table below hows a dramatic increase in fatalities at higher impact speeds.

Risk of pedestrian fatality upon collision with an approaching vehicle
Vehicle speed Odds of pedestrian death

20 mph


30 mph


40 mph


The role of ITS applications for enhancing pedestrian safety on the roads include:

  • detection of pedestrians at signal-controlled crossings
  • speed reduction at the approach to pedestrian-vehicle conflict points (such as school zones) through the use of roadside variable message signs linked to speed sensors or in-vehicle intelligent speed adaptation systems
  • improving the visibility of pedestrians through movement-activated roadside lighting and on-vehicle blind spot monitoring systems
  • raising awareness of potential conflicts – for example by providing countdown displays at crossings to alert the pedestrian to the green-time available for crossing
  • improving vehicle design for pedestrian protection – for example autonomous emergency braking systems which are activated to avoid collision or reduce the force of impact, when a vehicle senses that a collision is imminent

New ITS-based developments include:

  • dynamic traffic signal control activated by pedestrians carrying Radio Frequency Identification (RFID) devices that communicate directly with traffic lights
  • pedestrian activated warning signs that detect the presence of pedestrians waiting to cross the road
  • pedestrian warning lights to highlight for drivers, the presence of pedestrians

The key to putting appropriate measures in place is to identify where interventions are needed - high risk accident zones and locations – and to review the effectiveness of available countermeasures. (See Accident Analysis)

Further Information

WHO (2013) Pedestrian safety: a road safety manual for decision-makers and practitioners.


Encouragement of cycling as a mode of transport is one way of contributing to sustainable transport objectives. In most countries levels of cycling have declined with increased use of cars, vans and motorised two-wheelers – but an upward trend has been observed recently in highly urbanised areas such as Paris and London linked to deployment of ITS back-office support for city-wide bike hire schemes.

A significant barrier to achieving uptake of cycling are widely held concerns about road safety - due to the amount of traffic on the roads as insufficient provision of cycling-friendly infrastructure.

The role of ITS applications for enhancing cyclist safety include:

  • traffic signal prioritisation based on the detection of cyclists - detection can be active (inductive loops) or passive (user activated)
  • intelligent cycling infrastructure which reflect patterns of cycle flows within defined areas (such as major destinations – schools, train stations or a university campus)
  • bicycle route planning as part of a wider journey planning ITS application supported by turn-by-turn navigation for the cyclist

New developments to benefit cyclists include:

  • crowd sourcing of digital maps which take account of road features that are obstructive to cyclists – such as dangerous intersections, cobbled streets, uneven road surfaces, pot holes and steep hills
  • bicycle-based devices that enhance the visibility of cyclists to other road users by projecting images ahead of, or to the side of, the bicycle
  • vehicle-based cycle detection systems – which are broadly of two types:
    • blind spot monitoring systems
    • systems that communicate with a Radio Frequency Identification (RFID) tag fitted on the bicycle - and other cooperative systems which register the presence of cyclists

The key to putting appropriate measures in place is to identify sites which are of concern for cyclist safety such as problematic junctions and roundabouts – together with assessing user acceptance of specific solutions, whether they are cyclists, drivers or other road users including nearby residents.

Further Information

Rutgersson (2013) A study of cyclists' need for an Intelligent Transport System. Masters dissertation. Chalmers University of Technology: Göteborg, Sweden.

Jordova et al (2012) Recommendations on standardisation, deployment and a research agenda. Deliverable D5.1 of the SAFECYCLE project.

De Jong et al (2012) State of the art applications to enhance the safety of cycling. Deliverable D2 of the SAFECYCLE project.

Children, Elderly, Disabled

Children, elderly and disabled are particularly vulnerable to road accidents. These groups have less resilience to falls or collisions and may have limited mobility. They often rely on mobility aids – walking sticks, wheelchairs and pushchairs. Children in particular have a great propensity to be distracted, and when they gain independence they are often inexperienced in road use and its consequences.

The role of ITS applications that benefit the safety of these vulnerable road users include:

  • Speed reduction at potential conflict points such as school zones, hospitals and sheltered housing – for example:
    • Speed Indicator Displays (SIDs) that display a motorist’s speed to encourage drivers to slow down (some include a smiling face)
    • in-vehicle intelligent speed adaption
  • improving driver awareness of the presence of highly vulnerable pedestrians
  • improving vehicle design to assist elderly and disabled drivers including in-vehicle information and control systems such as:
    • collision warning system, blind spot and obstacle detection systems, and e-call
    • routing advice to avoid specific types of road (such as motorways)
  • “intelligent” facilities for pedestrians – for example extending pedestrian crossing time for signalised crossings at appropriate locations. These can be enhanced by features that help people who have a sight or hearing impairment (using tactile and audible prompts)

The key to putting appropriate measures in place is to identify installation locations where pedestrians are at risk – such as crossing points or junctions adjacent to schools, nursing homes, or a high concentration of disabled pedestrians.

Road Workers

Roadworks occur all the time on the network. Highway authorities and road operators carry out maintenance and improvement works such as road widening, resurfacing, bridge and gantry maintenance, white line painting, litter collection and gully emptying. The providers of utilities such as gas, electricity, water, sewage and telecommunications - also carry out maintenance and repairs to their infrastructure located alongside or below the road.

Road workers are commonly exposed to serious risk of accidents and fatalities. Vehicle speed is often a key factor in road worker fatalities. The role of ITS application in reducing these risks include:

  • information and advance warnings to drivers through dynamic signs about the presence of road workers - including the temporary deployment of portable dynamic signs
  • speed management using variable speed limits and camera enforcement. Automatic Number Plate Recognition (ANPR) can be used to support enforcement or to display an offending vehicle’s registration number on a dynamic message sign to influence driving behaviour

The key is to make drivers aware of the presence and vulnerability of road workers. (See Work Zones)

Further Information

Safety at street works and road works: a code of practice 2013 (UK)

US Department of Transportation: work zone mobility and safety program

Working Animals

Working animals include guide dogs that help the visually impaired people and horses carrying riders or pulling carts that share the roadway. All are at risk of accidents, many of which are preventable.

There is very little reported experience of technology solutions for working animals. A potential application – for guide dogs and visually impaired people - would be cooperative systems which combine geo-location with communications - for example:

  • between the guide dog and the road infrastructure and/or vehicles
  • and by providing voice guidance and safety messages to the person at dangerous locations

This could be achieved through a combination of Global Positioning Satellites and Radio Frequency Identification. A similar concept might be appropriate for horse riders and horse drawn carts – enabling communication between the equipment worn on the animal and the road infrastructure.



Reference sources

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