Killing Speed: a good Practice Guide to Speed Management

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Killing Speed: A Good Practice Guide to Speed Management

© Slower Speeds Initiative 2001
Speed management is central to road safety. Controlling speeds at appropriate levels is the most significant action local authorities can take to meet national targets for reducing road traffic casualties. In order to be effective, speed management requires active partnership between highway authorities, the police and local communities. Only through such collaboration can the four Es of speed management – Engineering, Enforcement, Education and Evaluation– deliver real road safety gains.
This Guide aims to support local authorities in their responsibility for reducing road traffic casualties and improving road safety. It brings together examples of effective speed management schemes which have already been introduced by local authorities. It also provides guidance in creating environments which reduce the danger caused to vulnerable road users by motor traffic, in both urban and rural areas.
The majority of examples in the Guide come from within Britain, where the ‘transferability’ of schemes is relatively unproblematic. There are also some examples of good practice from other countries, in order to illustrate the potential benefits of particular approaches to speed management.
The Guide takes account of relevant national policies and policy guidance documents, including:
A New Deal for Transport – Better for Everyone: The Government’s White Paper on the Future of Transport (DETR, 1998)

Modern Local Government: In Touch with the People (DETR, 1998)

Independent Inquiry into Inequalities in Health (Stationery Office, 1998)

Rural Safety Management (Institution of Highways and Transportation, 1999)

Places, Streets and Movement: A Companion Guide to Design Bulletin 32 (Residential Roads and Footpaths) (DETR, 1998)

Saving Lives: Our Healthier Nation (Department of Health, 1999)

Tomorrow’s Roads – Safer for Everyone: The Government’s Road Safety Strategy and Casualty Reduction Targets for 2010 (DETR, 2000)

New Directions in Speed Management: A Review of Policy (DETR, 2000)

Guidance on Full Local Transport Plans (DETR, 2000)

Transport 2010: The 10 Year Plan (DETR, 2000)


Casualty reduction

There is overwhelming evidence that lower speeds result both in fewer collisions and in reduced severity of collisions (Finch et al, 1994; MASTER Project, 1999). One of the most powerful research findings of recent years has been that an increase in average speed of 1mph results in an average 5% increase in the total number of crashes. Correspondingly, a 1mph reduction in average speed results in an average 5% reduction in crashes. This means that even marginal reductions in average speeds can result in major road safety gains.
Research by the Transport Research Laboratory shows that the reduction varies by road type, as follows:
around 6% for urban roads with low average speeds

around 4% for medium speed urban roads and lower speed rural main roads

around 3% for higher speed urban roads and rural main roads

Furthermore, a reduction of just 2mph in average speeds could result in an annual saving of around 23,000 casualties nationally, including more than 200 deaths and around 3,500 serious casualties (Taylor et al, 2000). The cost benefit to society from such a reduction in casualties would be over £830 million per year (DETR, 2000a).

Fatality rates also increase sharply with speed. A recent government road safety message warns drivers that they are twice as likely to kill someone when travelling at 35mph as they are at 30mph. Yet already 90% of pedestrians hit by a car travelling at 30mph will be seriously injured. Nearly half of them will be killed (DETR, 2000b).
There is also a distributional effect across society. The impact of vehicle speed is felt more by children and young people and those living in poorer communities; child pedestrian fatalities in socio-economic classes IV and V are five times those in class I. Moreover, reductions in speeds driven result not only in fewer physically harmed children (over 60% reduction in casualties in 20mph zones) but also in fewer psychological problems too. This is often overlooked. Children involved in road crashes appear to suffer more post-traumatic stress than adults, and girls slightly more so than boys. Research suggests that over one third of children involved in such crashes suffer post-traumatic stress, as opposed to one fifth of adults (Stallard et al, 1998).
The Independent Inquiry into Inequalities in Health (1998) made specific reference to the need to address inequalities arising from traffic speed. It recommended:
"further measures to reduce traffic speed, by environmental design and modification of roads, lower speeds in built up areas, and stricter enforcement of speed limits." (Independent Inquiry into Inequalities in Health, 1998, p61)

Benefits to children and young people

Slower traffic speed is of immediate relevance to children and young people as they are major users of the outdoor environment, through play, school travel, leisure activities and employment. Walking and cycling are important for long-term health and well-being, and establishing a habit of physical activity early in life helps to foster an active lifestyle in adulthood. Walking and cycling can help children to learn about their local environment, acquire and develop road sense, assess risk and learn to rely more upon themselves (Moore, 1986).
In addition, being physically active can help children build a strong sense of identity, make creative use of their own minds and develop the capacity to take responsibility for themselves (Kegerreis, 1993). Speed management initiatives such as 20mph zones can significantly reduce parental fears about traffic safety and traffic danger, at the same time as they promote children’s health.
Restoring freedoms to communities
There is an inverse relation between motor traffic volume and street level non-traffic activity: the more traffic there is, the less streets are used by people (Appleyard, 1981). Neighbourhoods which are dominated by high traffic volumes and speed are indicative of communities stripped of their ‘social capital’ (Kawachi et al, 1997), and quality of life declines. Cyclists and pedestrians find it harder to get around. Older people and families with young children report that high road traffic volumes result in insecurity (Kaeboe, 1992; Copenhagen Healthy City Project, 1994).
The severance effect of motor traffic reduces access for those travelling on foot or by bicycle to health promoting facilities, including shops, health facilities, parks and friends. The latter is important because of the health protective function of social support networks (Fox, 1988; Glass et al, 1999) and the evidence that lack of social support can increase mortality from coronary heart disease by up to four times (Greenwood et al, 1996). Good social support networks are most important for vulnerable groups, such as children and the elderly.
Economic benefits
The government has stated that speed is the major factor in one third of all road crashes (DETR, 2000c). This figure is widely believed to be too low. Evidence from projects to reduce traffic speeds indicates that speed is the major factor in up to 50% of all road crashes, and a contributory factor in many more.
Yet applying even the government’s one third figure indicates the scale of economic impact caused by speed-related crashes and casualties. DETR puts the total value of prevention for all crashes and casualties in Britain during 1999 at an estimated £16.3 billion (DETR, 2000a). On these figures, preventing the one third of road crashes in which the government identifies speed to be the major factor would bring society a cost benefit of over £5 billion per year.
In addition, if reduced speeds help to reduce perceived and actual road danger, more people will choose to make journeys by alternative modes to the car. Aside from providing increased opportunities for people to be physically active (in itself a Department of Health recommendation in order to help reduce the incidence of heart disease and stroke), such a change in travel behaviour could also help to improve air quality.
This would be especially important in towns and cities, and could lead to a reduction in the demand for health services. The Department of Health’s Committee on the Medical Effects of Air Pollution (COMEAP) has estimated that periods of high air pollution may hasten up to 24,100 deaths each year in Britain, mainly among older and less healthy people. A further 23,900 hospital admissions are brought forward, in addition to extra admissions. This does not include chronic effects. It is likely that long-term exposure to air pollutants also damages health, although this is currently not quantifiable (Department of Health, 1998). Correlations between neighbourhood traffic volumes and child respiratory symptoms have also been reported (Duhme et al, 1996; Oosterlee et al, 1996; Boezen et al, 1999), including hospital admissions for asthma (Edwards et al, 1994; Weiland et al, 1994).
In suburban and rural areas there are likely to be comparable but so far unexamined problems of health and social exclusion brought about by unsuitable traffic conditions on minor roads (which constitute 60% of the overall road network in Britain). The Greenways and Quiet Roads projects initiated by a number of local authorities, including Kent and Norfolk, attempt to tackle precisely this issue.
Wider environmental benefits
Many additional benefits would result from drivers choosing appropriate speeds on all classes of roads. On high speed roads and those in urban areas where smoother driving styles are achieved through speed management, both fuel consumption and air pollution can be reduced through lowering speeds. Driving at 50mph instead of 70mph can reduce fuel consumption by 30%. Interurban road journeys thus offer immediate scope for reductions in CO2 emissions.
Half of all journeys made in Britain are less than two miles in length. When driven from a cold start, these journeys produce disproportionate amounts of CO2. A road environment which encourages more people to make these shorter journeys on foot or by bicycle should be a priority in the quest for CO2 reductions.
Road traffic is the most important source of noise nuisance, and noise increases with speed. In addition, lower and better enforced speed limits would reduce the pressure for road building by increasing the capacity of the existing highway network. Lower speeds can also help to reduce the damage done by heavy goods vehicles, and thus reduce road maintenance costs (Plowden and Hillman, 1996).
Transport 2010: The 10 Year Plan
In July 2000 the government published its 10-year strategy for transport expenditure. A total of £180 billion is to be invested in road and rail over the next 10 years. Of this, £59 billion is to be spent on local transport, out of which £30 billion is allocated to highway maintenance. The remainder amounts to a doubling of the funds available to highway authorities in 2000-01. There are therefore unprecedented opportunities to fund environmentally sustainable programmes, such as:
safer walking and cycling routes

more 20mph and home zones, particularly around schools

the extension of Rural Bus Subsidy Grants to cover more journeys serving market towns

a one third increase in the proportion of rural households living within 10 minutes’ walk of an hourly (or better) bus service

Review of Speed Policy and Road Safety Strategy

The government set up a review of speed policy as an outcome of its Transport White Paper (DETR, 1998). The review was:

"to develop a speed policy that takes account of the contribution of reduced speeds to environmental and social objectives as well as to road safety." (DETR, 2000b, p7)

The findings of the review are reflected in the government’s Road Safety Strategy (DETR, 2000c); both reports were published in March 2000.

At its launch, the Prime Minister affirmed that controlling speed lies at the heart of the Road Safety Strategy (UK Government, 2000). Yet the Strategy focuses principally on compliance with existing speed limits rather than on reducing them to more appropriate levels. It should therefore provide the starting point for more ambitious local speed management strategies drawn up in conjunction with local communities.
The Road Safety Strategy states that DETR will revise its guidance to local authorities "on the setting of local speed limits to achieve appropriate and consistent national standards to reflect, as far as possible, the needs of all road users on different classes of roads" (p49). In addition, it identifies the need to:
develop new hierarchies of rural and urban roads defined by their function and quality, which would combine flexibility at the local level with consistency nationally

provide better information to help drivers choose appropriate speeds, including more effective speed limit signing, speed-activated signs at hazards, and additional signing for speed cameras

target enforcement (including use of speed cameras) to improve compliance and safety

make changes to simplify the making of speed limit orders by highway authorities.

The Road Safety Strategy encourages local authorities to use the increased powers they have to introduce 20mph zones and speed limits in residential areas. It suggests that this should be a priority in areas with large numbers of children, such as near schools. It also sets casualty reduction targets for road traffic collisions by the year 2010 (against an average for 1994-98). These are:

a 40% reduction in the number of people killed or seriously injured

a 50% reduction in the number of children killed or seriously injured

a 10% reduction in the slight casualty rate

The government’s Guidance on Full Local Transport Plans (DETR, 2000d, para 186) repeats the Road Safety Strategy’s call for local authorities to take action on speed management:

"local safety strategies should include speed management to achieve safe vehicle speeds on all roads and ensure that the speed limits set are appropriate, consistent and enforceable (agreed with the police), especially where children are about. Traffic calming measures should be employed to encourage both speed reduction and compliance with limits... Self-enforcing 20mph zones have proved very effective at reducing both the likelihood and severity of accidents."

As a public response, safety and environmental groups have advocated stronger action on speed, and specifically more efforts targeted at speed reduction. For example, the national coordinating group Transport 2000 has especially called for a speed limit reduction to 20mph on built-up roads, in order to halve child deaths and serious injuries. Transport 2000 has also called for a Safe Streets Fund to pay for more traffic calming. At present the British government and local authorities spend around 10p per head per year on traffic calming. Their Dutch equivalents spend £1.60 (Transport 2000, 2000).

The Society of Chief Officers of Transportation in Scotland has proposed a ‘zero tolerance’ approach to breaking speed limits. This has included the introduction of ‘speed wardens’ to issue routine fines for everyday offences, thus freeing up police resources and "increasing the likelihood of being ‘done’ for speeding so much that nearly everyone sticks to the limits" (Society of Chief Officers of Transportation in Scotland, 1999).

The government’s Review of Speed Policy and Road Safety Strategy remain wedded to an ethos of casualty reduction rather than a wider ethos of danger reduction. Communities and local authorities need to take this further in order to achieve the wider road safety benefits which speed reduction offers.
Nonetheless, the Road Safety Strategy can still stimulate positive changes in street design, road user attitudes and behaviour and a more effective use of enforcement technology. Speed management can in turn support other recent national policy initiatives to increase levels of walking and cycling. Guidance on Full Local Transport Plans states that national government will be looking to local authorities to demonstrate that they will implement policies to promote walking and cycling (paras 120-128). Local authorities are expected to make their contribution to the national target of quadrupling the number of cycle trips by 2012 from the 1996 baseline, and Local Transport Plan funding in subsequent years will be determined, in part, by the progress which local authorities make on such issues. Without effective road speed management, these targets for non-motorised travel are unlikely to be met.
It is inspirational to learn of the ambitious goals set in other European countries and the philosophies which underpin them. In both Sweden and the Netherlands, as elsewhere, the national governments have had to consider competing political demands, such as the balance between economic prosperity, environment and safety. They have concluded that stronger action needs to be taken to reduce deaths and injuries arising from transport activity. They take account of the fundamental vulnerability of the human body and the consequent need to reduce the potential for collisions at speeds which threaten life and limb.
This means that the safety of the most vulnerable is the litmus test for the safety of their overall road transport system. Such an approach reflects the knowledge that a pedestrian struck by a vehicle at 20mph or less will most likely receive only a minor injury, but that a pedestrian struck by a vehicle at 30mph or above will most likely be seriously injured, and very possibly killed (Ashton and Mackay, 1979; Kallberg, 1999). This leads to the conclusion that speeds in mixed use sections of the road network must be reduced.
Sweden: Vision Zero
The Swedish parliament’s decision of 9 October 1997 to pursue a policy goal of no fatal or serious injuries is probably the most ambitious road safety policy of any Western government (Carlsson, 1998). The parliament has stated that:
"The long term goal is that no one should be killed or seriously injured within the Swedish road transport system, and the structure and the function of the road transport system must be brought into line with the demands this goal entails."
Within this goal, the most important measure is to reduce current traffic speeds. The transport system will always create a substantial number of crashes, but it is possible to limit the effect on the human body by reducing speeds to a level which will almost eliminate fatalities and prevent most serious injuries. Vision Zero requires that the needs of vulnerable road users determine the safety demands on the system. For example, on streets where pedestrians and cyclists cannot be effectively separated from cars, the speed of the cars must be reduced to below 30kph in order almost to guarantee that no one is killed in a crash. Calculations show that investments in a safer road environment of around £7-10 billion can reduce the number of fatalities by 80-90% per year. The socio-economic cost of the crashes and casualties is an estimated £3.3 billion per year (Carlsson, 1998).
The Swedish government has established a target for the minimum pace of improvement, stating that the national total of fatalities should not exceed 400 in the year 2000 and 250 by 2007. In order to achieve this, every fatality – and later on every serious injury – will have to be investigated with the aim of finding out what could have been done to prevent it. To advance Vision Zero further, the Swedish government introduced an 11-point programme in 2000. The most important aspects of this were more efficient speed enforcement using speed cameras, and the lowering of speed limits (Carlsson, 2000).
The Netherlands: Sustainable Safety Programme
The Netherlands instigated its Sustainable Safety Programme in 1997 (Wegman, 1997; Ministry of Transport, Public Works and Water Management, 1997; Talens, 1999). The demands of the programme for traffic and transport are:
infrastructure adapted to the limitations of human capabilities

vehicles equipped to simplify the tasks of drivers and constructed to protect vulnerable road users

adequate education and information for road users

Measures taken as part of the start-up programme for Sustainable Safety since 1997 include:

a road classification (road hierarchy) programme for the complete Dutch road network, which enables the roads to fulfil their functions satisfactorily and forms a basis for solving problems of contradictory requirements

a low-cost introduction of 30kph zones inside built-up areas so that 50% of the possible zones are implemented by 2000 (excluding roads with a ‘flow function’, enabling high speeds for long distance traffic and high traffic volumes, and those with a ‘distributor function’, serving scattered destinations)

implementing 60kph zones for minor rural roads, with some 3,000km to be achieved by 2000

a public information campaign to support the introduction of Sustainable Safety, as well as better police enforcement and education programmes

Both the Swedish and Dutch policies are equity-based in that they recognise that speed has distributional effects in the way that different road users (and residents) are affected.
Speeding is endemic
The majority of drivers regularly break speed limits. This is true for all classes of roads, all times of day and all days of the week (DETR, 1999). It is testimony to the fact that speeding is not confined to a deviant minority. Indeed, many drivers treat posted speed limits as minimums rather than maximums, and fail to recognise the risks they pose to themselves, their passengers and those outside their vehicles (McKenna, 1994).
A key finding of the European MASTER project (Managing Speeds of Traffic on European Roads) is that just having speed limits by themselves is insufficient for managing speeds at a desired level. For example, 90% of pedestrian and cyclist fatalities in London (roughly 150 per year) occur on 30mph roads. A Metropolitan Police survey found that 63% of all drivers on such roads exceed the speed limit – that is, two million drivers driving over 30mph in London alone. The survey, carried out during June and July 1999 on 10 roads in London with 30mph limits, found that of those drivers breaking the speed limit, 10% were driving at over 50mph and a very small percentage (but still hundreds of drivers) exceeded 70mph.
Motorists choosing to drive at the highest speeds pose the greatest risk to vulnerable road users. Yet all speeding traffic imposes costs on society beyond the tragedies of road crashes. In the words of Chief Inspector Brooks of the Metropolitan Police:
"When traffic speeds up it becomes much more difficult for pedestrians, for instance, and in particular the elderly and the young, to actually cross roads because the opportunities are reduced. You could call it road theft – it is about road exclusion for significant sectors of road users." (Traffic Engineering and Control, 2000)

Breaking the speed limit is one form of excess speed. Another is inappropriate speed: driving within the speed limit but too fast for the conditions. On 27 November 2000 the High Court awarded £3.5 million damages to a schoolboy hit by a car travelling within the 30mph speed limit in west London. Insurers for the driver – who had been warned by local residents on several occasions to drive more carefully – accepted that he had been negligent. Residents had long campaigned for a reduction of the speed limit in the area, which they had covered with ‘Kill Your Speed’ posters.

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