MANAGEMENT OF TRAVEL SPEEDS ON THE ROAD NETWORK

MANAGEMENT OF TRAVEL SPEEDS ON THE ROAD NETWORK

Speeding is correctly recognized as the largest single behavioral contributor to road deaths globally, and this is also true of Brazil. Speeding is the key factor in road related trauma as identified in best quality research and reviews⁹³ including by world leading authorities: the World Health Organization, World Bank, and Global Road Safety Partnership⁹⁴ as well as the OECD⁹⁵.

A common misunderstanding is that speeding increases the severity of crashes, but does not cause crashes. Speeding contributes to the occurrence of crashes in a number of ways as well as contributing to the severity of the crash through: reducing capacity to stop in time; reducing maneuverability in evading a crash; making it impossible to negotiate curves and corners at speeds above those which simple physics will allow for the friction available; and causing others to misjudge gaps, for example by allowing pedestrians less gap to cross the road than expected because the vehicle is travelling above the speed limit.

Furthermore, in official figures speeding is generally underestimated as a factor in fatal and serious crashes. This claimed under-estimation in official figures is demonstrated by the effects of speed cameras in other countries. For example, official estimates (based on Police reports) indicated that speeding contributed to around 35 to 40% of fatal crashes in the state of New South Wales (NSW, the most populous state of Australia), yet the independent evaluation of the NSW fixed speed cameras revealed that at treated locations, the cameras resulted in a 71% reduction in speeding and an 89% reduction in fatalities⁹⁶. Because speed cameras only address speeding as a crash factor, these results suggest that speeding was contributing to most fatalities (at least 89%) not merely 35 to 40%. Evaluations of point-to-point (or section control) cameras in Europe has revealed similarly dramatic reductions in serious crashes when speeding is managed.

Travel speeds commonly remain excessive, and are a key contributor to both crash occurrence and severity. Part of the reason for this is the high tolerance which is accepted above the speed limit before drivers are penalized for speeding along with the low probability of being caught. Thus, engineering works are required to reduce speeds at many locations. Simply getting motorists to obey the speed limits would save many lives in Brazil.

Police officers in Brazil agree that official figures result in an under-estimate of the problem, with some estimating that speeding is a key factor in as much as 80% of fatal crashes. Speeding is readily observed on roads throughout Brazil, and this has been confirmed by a survey of speeds conducted in the state of Bahia for the Bank’s assessment there.

Speed Surveys in Bahia

Following the observation of cases of excessive speeding by the World Bank assessment team, a small on-road objective speed survey was conducted for the World Bank team by State Military Road Police. The study was undertaken in daylight on rural Highways BA262 and BA263 to check speeding. Police placed radars at several locations along these highways in 80km/h and 40km/h speed limit zones. The speed surveys confirmed a serious speeding problem on both highways: In the two locations on 80km/h zones excessive speeds were common: in a few hundred vehicles the following speeds were recorded: 147, 136, 130, 111, etc. For one of these locations the average speed of identified vehicles was 98km/h (18km/h above the limit). In 40km/h zones, many instances of speeds over 70km/h were observed, and for one of these locations speeds average 69km/h (29km/h above the speed limit). Such speeds are major contributors to crash occurrence and severity, and cannot be allowed to continue.

The success of speed cameras in reducing road deaths and serious injuries is irrefutable. Two practical examples of government management of speed cameras from Australia support the broad international reviews of evidence cited above. In the state of New South Wales, as noted above, independent analysis of the fixed speed camera program showed huge benefits at camera locations: speeding down by 71%, fatalities down by 89%, and injuries down by 20%.⁹⁷ Second, Police discontinued using mobile speed cameras in NSW and the cameras were not re-implemented until the NSW Centre for Road Safety was allowed to take over the program over a year later, after a large increase in the road toll. When the cameras stopped operation deaths rose by 21% and when the cameras were re-introduced the next year the deaths decreased by 11% but took another year to return to lower levels than before the cameras were discontinued.⁹⁸ Speed camera enforcement has been shown repeatedly to reduce the toll of deaths and injuries⁹⁹. Numerous studies have been reviewed by the OECD¹⁰⁰, and by the Cochrane Library Review,¹⁰¹ both concluding that the evidence shows that speed cameras clearly provide substantial Road Safety gains in terms of reduced deaths and injuries.

Fixed and mobile speed cameras are in use on federal highways, state highways and in some municipalities (Figure 21). However, federal requirements for visibility and signage (Figure 22) of cameras limit the cameras to primarily operating as location specific treatments rather than being able to provide a broader suppression of speeding across the network, which is preferable. Research has shown that generally drivers slow for signposted or visible cameras and speed up after they pass them.

Figure 21. Static (moveable) and fixed cameras in São Paulo state.



Figure 22. Extensive speed camera warning signs on urban and open roads in Brazil.



Figure 23. 85^th percentile speeds recorded on approach and departure around a sign-posted speed camera in in an 80km/h speed limit in New South Wales (Australia), showing the limited extent of effect of this approach to speed enforcement.

Signposted speed enforcement slows drivers down for around 600 m (see Figure 23 for the results of a study of the effects of a signposted speed camera in the state of New South Wales, Australia¹⁰²). Applying this finding of speed camera effects for about 600 m to Brazil, in which speed cameras are typically sign-posted, means that only a tiny proportion of the road network is effectively enforced for speeding.

In many instances, the fixed cameras are not in themselves highly visible which is an excellent feature encouraging broader suppression of speeding. Mobile cameras operate without signage, providing a balance to the signage around fixed cameras, though this is somewhat limited in effect by the requirement for visibility. In addition, penalties are sometimes avoided and are not sufficient to deter many drivers.

Speed limits in Brazil are also too high for the road usage occurring in many instances and should be reviewed. Although speed limits on rural roads are generally either appropriate or not far from appropriate for the environments in which they exits (with a few exceptions), travel speeds commonly remain excessive, and are a key contributor to both crash occurrence and severity.

Finally, it is important to employ road engineering treatments for speed management and to retain existing treatments such as speed humps and cobblestones which reduce traffic speeds. This can include transverse rumble strips, speed humps which should be sued more as an effective treatment, gateway treatments, and other devices (for examples see Figure 24).

Figure 24. Effective speed reduction device in Anhembi city, São Paulo state, and cobblestones in Bahia.

There is little results focus on speeding in Road Safety management, with no apparent intermediate outcome measures in use for monitoring. Within senior Police and some areas of government (including DNIT) there is a sound appreciation of the need for speed enforcement and speed management generally. However, more broadly in the community and among many government officials there is insufficient appreciation of the role of speed in serious crashes, and speeding continues to be normal and accepted behavior on the roads of the country.

It is important to appreciate that higher speeds are not simply better for the economy, because the costs of crashes, injuries, pollution, and fuel all increase.