Speed Enforcement Research Articles

The Importance of ‘Blue Shirts’ in Traffic Policing

Abstract The requirement for transparency and accountability for public spending has seen a focus on quantitative cost–benefit analyses. In the context of traffic policing, the temptation is to emphasize the importance of automated systems of enforcement as these pose an arguably less expensive alternative to using uniformed police. In the context of speed enforcement, automated means of enforcement are a logical way to efficiently distribute resources. However, in other areas of traffic policing, like driver distraction, seatbelt use, random breath testing, the use of uniformed police is essential. Following an overview of empirical research examining traffic enforcement, this article explores theoretical explanations for compliance with the law, focusing on research that has examined the importance of procedural justice. It is suggested that an approach embracing both automated means of enforcement coupled with visible police presence is essential to encourage perceptions of procedural justice and police legitimacy. Further empirical research is needed to model the ideal allocation of funding across automated and non-automatic law enforcement in traffic to maximize public compliance with the law and ultimately reduce crashes.

Safety evaluation of four safety countermeasures on freeways in South Korea

We used data from seven freeways in South Korea to evaluate the safety impact of four safety countermeasures: (1) automated speed enforcement cameras, (2) chevron signs, (3) delineator posts, and (4) shoulder rumble strips. The evaluation was based on crash data from 2001 to 2008 and provided three years of before data and three years of after data for each countermeasure. We developed crash modification factors (CMFs) to show the safety impact of the countermeasures. We used the empirical Bayes before and after method to avoid regression-to-the-mean bias and take into account the impact of traffic volume changes in the before and after periods. We developed a safety performance function using a set of reference sites and a negative binomial regression technique. The CMFs for all crash data appeared that automated speed enforcement cameras and chevron signs decreased the frequency of crashes while delineator posts and shoulder rumble strips did not. The results were expanded by developing CMFs separately according to crash severity and crash type. The crash severity was divided into fatal and injury (FI) and property damage only (PDO) while the crash type was only focused on speeding-related crashes due to data limitations.

OTOMATİK KORİDOR HIZ KONTROLÜ’NÜN BİR EĞİTİM YERLEŞKESİNDEKİ TEKRARLI SÜRÜCÜLERDEN OLUŞAN BİR ÖRNEKLEM ÜZERİNDEKİ GÖRÜŞLER VE HIZ ETKİLERİ ÜZERİNE ANALİZİ

Trafikte kazalara sebep olan yüksek hız problemini çözmek için uygulanan hız denetim sistemlerinden biri olan Otomatik Koridor Hız Kontrolü, dünya çapında son derece yüksek seviyede motorize olmuş ülkelerde popülerliği artan yeni ve gelişmiş bir akıllı ulaştırma sistemi uygulamasıdır. Bu makalede bir üniversite kampüsü içindeki düşük hız limitli güzergâhlara 2013 yılında mobil olarak kurulan bu sistemin, tekrarlı (her gün kampüse gidip gelen) sürücülerin önce/sonra dönemlerindeki hızlarına ve görüşlerine etkisini araştıran bir çalışma sunulmaktadır. Sürücülere yapılan anketlerden ise 729 adedi geçerli sayılmıştır. Titizlikle yapılan tespitlere göre; anket katılımcılarından sadece 32 adedinin önce/sonra dönemlerinin her birinde en az 8 kere sistem tarafından ortalama hızları tespit edilenler olduğu tespit edilmiştir. Önce dönemine ait hızların ortalaması 38.73 km/s iken, sonra döneminde hızlar 35.13 km/s’e düşmüştür. Sürücülerin kampüste uygulanan hız limitleri hakkındaki düşünceleri sorulduğunda ise, %3.3’ü hız limitlerinin yüksek olduğunu, %56.7’si düşük olduğunu, %36.7’si ise yeterli olduğunu belirtmiştir. Ankete katılan ve ortalama hızları tespit edilen sürücülerin “cinsiyet, yaş, görev, kaza sayısı, hız sınırı hakkında düşünceler” değişkenlerine göre önce/sonra dönemlerine ait ortalama hız farklılıklarını bulmak için Bağımsız iki örnek T testi kullanılmış “eğitim düzeyi, araç kullanma yılı, diğer aracı geçme eğilimi” değişkenlerinin önce/sonra dönemlerine ait ortalama hız farklılıklarını bulmak için ise Tek değişkenli varyans analizi yapılmıştır. Analize göre farklar anlamlı değildir. Cezai yaptırım olmaksızın ortalama hızlar anlamlı düşüş göstermiştir; fakat hız sınırlarına daha yüksek bir uyum, bir uygulama yaptırımı ile sağlanabilir. Sürücülerin kaza geçmişleri ile ortalama hızlarındaki düşüşler arasında anlamlı fark görülmemiştir.

Towards Low-Carbon Interurban Road Strategies: Identifying Hot Spots Road Corridors in Spain

Reducing traffic emissions is key in transport planning and infrastructure management in order to achieve a sustainable transport system. This paper contributes to this topic in two ways. The first step describes a comprehensive methodology for identifying hot spots road segments and corridors with problems of GHG emissions to enable low-carbon actions. The Highway Energy Assessment (HERA) methodology is applied to the national road network of Spain in order to estimate interurban traffic emissions and calculate the emissions index to assess strategies. The results are shown graphically on a GIS, allowing to identify seven corridors with emissions problems comprising 25% of the network and being responsible for 51% of the total GHG emissions in 2012. Inefficient corridors were those with high rates of heavy vehicles, high speeds and steep gradients. The second step consists of the application of a set of strategies to reduce their emissions and their comparison to the reference scenario. The Mediterranean corridor—the most inefficient corridor—was selected to apply a set of abatement strategies. The most effective strategy was speed enforcement for light vehicles. A speed reduction of 10 km/h could produce a 3.5% savings in emissions compared to the reference scenarios, and decrease emissions intensity from 254 gCO2eq/veh-km to 246 gCO2eq/veh-km.

Impact of automated photo enforcement of vehicle speed in school zones: interrupted time series analysis

ObjectiveMeasure the impact of automated photo speed enforcement in school zones on motorist speed and speeding violation rates during school travel.MethodsAutomated enforcement cameras, active during school commuting hours, were installed...

An examination of the increases in pedestrian motor-vehicle crash fatalities during 2009–2016

IntroductionPedestrian fatalities increased 46% in the United States during 2009–2016. This study identified circumstances under which the largest increases in deaths occurred during this period. MethodAnnual counts of U.S. pedestrian fatalities and crash involvements were extracted from the Fatality Analysis Reporting System and General Estimates System. Poisson regression examined if pedestrian fatalities by various roadway, environmental, personal, and vehicle factors changed significantly during 2009–2016. Linear regression examined changes over the study period in pedestrian deaths per 100 crash involvements and in horsepower per 1000 pounds of weight among passenger vehicles involved in fatal single-vehicle pedestrian crashes ResultsPedestrian deaths per 100 crash involvements increased 29% from 2010, when they reached their lowest point, to 2015, the most recent year for which crash involvement data were available. The largest increases in pedestrian deaths during 2009–2016 occurred in urban areas (54% increase from 2009 to 2016), on arterials (67% increase), at nonintersections (50% increase), and in dark conditions (56% increase). The rise in the number of SUVs involved in fatal single-vehicle pedestrian crashes (82% increase) was larger than the increases in the number of cars, vans, pickups, or medium/heavy trucks involved in these crashes. The power of passenger vehicles involved in fatal single-vehicle pedestrian crashes increased over the study period, with larger increases in vehicle power among more powerful vehicles. ConclusionsEfforts to turn back the recent increase in pedestrian fatalities should focus on the conditions where the rise has been the greatest. Practical applicationsTransportation agencies can improve urban arterials by investing in proven countermeasures, such as road diets, median crossing islands, pedestrian hybrid beacons, and automated speed enforcement. Better road lighting and vehicle headlights could improve pedestrian visibility at night.

Using Traffic Signal Control to Limit Speeding Opportunities on Bidirectional Urban Arterials

Although controlling speed on urban arterials is important for safety, conventional traffic calming techniques cannot usually be applied on arterials, and many jurisdictions prohibit automated speed enforcement. Moreover, unlike unidirectional arterials, bidirectional arterials with short intersection spacing are not amenable to green waves that can remove the incentive to speed. This research explores the ways that traffic signal coordination creates – or limits – speeding opportunities on bidirectional arterials. Two measures of speeding opportunity are proposed: number of unconstrained vehicles, meaning vehicles arriving at a stopline on green and with no vehicle less than 5 s ahead of them, and number of speeders in a traffic microsimulation in which 20% of the vehicles have been assigned a desired speed in the “speeding” range. Theoretical analysis, confirmed by two case studies, show how speeding opportunities are related to degree of saturation, cycle length, specified progression speed (as in input to signal timing software), intersection spacing, and recall settings. The important role of clusters of intersections with near-simultaneous greens, a byproduct of bidirectional coordination with short intersection spacing, is examined. Clusters with many intersections are shown to create a strong speeding incentive, and cluster size can be reduced by lowering the cycle length and the progression speed. Case studies show it is sometimes possible to substantially reduce speeding opportunities with little or no increase in vehicular delay by lowering cycle length, lowering progression speed, dividing an arterial into smaller “coordination zones” with each zone having its own cycle length, and by abandoning coordination altogether.

Safety and operational impacts of setting speed limits below engineering recommendations

This study quantifies the operational and safety impacts of setting posted speed limits below engineering recommendations using field data from rural roads in Montana. Vehicle operating speeds and historical crash data were collected at multiple sites with posted speed limits set equal to engineering recommendations and sites with posted speed limits set lower than engineering recommendations. Linear, quantile and logistic regression models were estimated to predict mean operating speed, 85th percentile operating speed and speed limit compliance, respectively, as a function of various roadway characteristics and level of speed enforcement. The Empirical-Bayes before-after approach was also used to develop crash modification factors (CMFs) that describe the expected change in total and fatal + injury crash frequency when setting posted speed limits lower than engineering recommendations. Because safety data were collected over a long time period, temporal adjustments were incorporated to account for yearly changes in crash reporting, traffic characteristics and other variables. The results revealed that speed limit compliance worsened as the difference between the engineering recommended and posted speed limits increased. The presence of verified heavy police enforcement reduced both mean and 85th-percentile operating speeds by approximately 4 mph and increased speed limit compliance. The safety analysis found a statistically significant reduction in total, fatal + injury, and property damage only (PDO) crash frequency at locations with posted speed limits set 5 mph lower than engineering recommendations. Locations with posted speed limits set 10 mph lower than engineering recommendations experienced a decrease in total and PDO crash frequency, but an increase in fatal + injury crash frequency. The safety effects of setting speed limits 15 to 25 mph lower than engineering recommendations were less clear, as the results were not statistically significant, likely due to the small sample of sites included in the evaluation. Overall, the results suggest that setting posted speed limits 5 mph lower than the engineering recommended practice may result in operating speeds that are more consistent with the posted speed limits and overall safety benefits.

Well-Deployed Speed Enforcement can Help Achieve Vision Zero

Well-Deployed Speed Enforcement can Help Achieve Vision Zero

Off Camera

With probe data providing everything from weather and accident reports to speed enforcement and mapping, could traditional ITS be on its way out? Paul Willis assesses the current state of play, as the EU's recent eCall mandate looks set to send the connected vehicle revolution into overdrive

Effective interventions for unintentional injuries: a systematic review and mortality impact assessment among the poorest billion.

Between 1990 and 2015, the global injury mortality declined, but in countries where the poorest billion live, injuries are becoming an increasingly prevalent cause of death. The vulnerability of this population requires immediate attention from policy makers to implement effective interventions that lessen the burden of injuries in these countries. Our aim was two-fold; first, to review all the evidence on effective interventions for the five main types of unintentional injury; and second, to estimate the potential number of lives saved by effective injury interventions among the poorest billion. For our systematic review we used references in the Disability Control Priorities third edition, and searched PubMed and the Cochrane database for papers published until Sept 10, 2016, using a comprehensive search strategy to find interventions for the five major causes of unintentional injuries: road traffic crashes, falls, drowning, burns, and poisoning. Studies were included if they presented evidence with significant effects sizes for any outcome; no inclusions or exclusions made on the basis of where the study was carried out (ie, low-income, middle-income, or high-income country). Then we used data from the Global Burden of Disease 2015 study and a Monte Carlo simulation technique to estimate the potential annual attributable number of lives saved among the poorest billion by these evidence-based injury interventions. We estimated results for 84 countries where the poorest billion live. From the 513 papers identified, 47 were eligible for inclusion. We identified 11 interventions that had an effect on injury mortality. For road traffic deaths, the most successful interventions in preventing deaths are speed enforcement (>80 000 lives saved per year) and drink-driving enforcement (>60 000 lives saved per year). Interventions potentially most effective in preventing deaths from drowning are formal swimming lessons for children younger than 14 years (>25 000 lives saved per year) and the use of crèches to supervise younger children (younger than 5 years; >10 000 lives saved per year). We did not find sufficient evidence on interventions for other causes of unintentional injuries (poisoning, burns, and falls) to run similar simulations. Based on the little available evidence, key interventions have been identified to prevent lives lost from unintentional injuries among the poorest billion. This Article provides guidance to national authorities on evidence-based priority interventions that can reduce the burden of injuries among the most vulnerable members of the population. We also identify an important gap in knowledge on the effectiveness and the mortality impacts of injury interventions. Partly supported by the Fogarty International Center of the US National Institutes of Health (Chronic Consequences of Trauma, Injuries, Disability Across the Lifespan: Uganda; #D43TW009284).

A Vehicular Mobile Standard Instrument for Field Verification of Traffic Speed Meters Based on Dual-Antenna Doppler Radar Sensor.

Traffic speed meters are important legal measuring instruments specially used for traffic speed enforcement and must be tested and verified in the field every year using a vehicular mobile standard speed-measuring instrument to ensure speed-measuring performances. The non-contact optical speed sensor and the GPS speed sensor are the two most common types of standard speed-measuring instruments. The non-contact optical speed sensor requires extremely high installation accuracy, and its speed-measuring error is nonlinear and uncorrectable. The speed-measuring accuracy of the GPS speed sensor is rapidly reduced if the amount of received satellites is insufficient enough, which often occurs in urban high-rise regions, tunnels, and mountainous regions. In this paper, a new standard speed-measuring instrument using a dual-antenna Doppler radar sensor is proposed based on a tradeoff between the installation accuracy requirement and the usage region limitation, which has no specified requirements for its mounting distance and no limitation on usage regions and can automatically compensate for the effect of an inclined installation angle on its speed-measuring accuracy. Theoretical model analysis, simulated speed measurement results, and field experimental results compared with a GPS speed sensor with high accuracy showed that the dual-antenna Doppler radar sensor is effective and reliable as a new standard speed-measuring instrument.

Speeding in highway work zone: An Evaluation of methods of speed control

Highway workers frequently work in close proximity of live traffic in highway work zones, traffic accidents therefore have devastating effects on worker safety. In order to reduce the potential for such accidents, methods involving use of advisory signs and police presence have been used to mitigate accident risks and improve safety for highway workers. This research evaluates the magnitude of the speeding problem in highway work zones and the effects of four levels of police presence on improving work zone safety. Speed data were collected in six different work zone locations in northern and southern California and used to determine the magnitude and nature of speeding problem in highway work zones. In addition data were collected over 11 test-days in four work zones with four levels of police presence: radar speed display with police decal and lighting, passive use of a police vehicle with radar speed display, passive use of a police vehicle without radar speed display, and active police speed enforcement near work zones. This paper analyzes this data using statistical methods to evaluate the effectiveness of these different methods of speed control on the safety of the work zone. Four Measures of Effectiveness (MOE) were used in this evaluation consisting of average speed reduction, speed variance, 85th percentile speed, and proportion of high speed vehicles. The results indicate that all levels of police presence provided statistically significant improvements in one or more of the MOEs.

Road traffic accidents in children: the 'what', 'how' and 'why'.

Road traffic accidents (RTAs) in Singapore involving children were evaluated, with particular focus on the epidemiology, surrounding circumstances and outcomes of these accidents. Key factors associated with worse prognosis were identified. We proposed some measures that may be implemented to reduce the frequency and severity of such accidents. This was a retrospective study of RTAs involving children aged 0-16 years who presented to the Children's Emergency at KK Women's and Children's Hospital, Singapore, from January 2011 to June 2014. Data was obtained from the National Trauma Registry and analysed in tiers based on the Injury Severity Score (ISS). A total of 1,243 accidents were reviewed. RTA victims included motor vehicle passengers (60.4%), pedestrians (28.5%), cyclists (9.9%) and motorcycle pillion riders (1.2%). The disposition of emergency department (ED) patients was consistent with RTA severity. For serious RTAs, pedestrians accounted for 63.6% and 57.7% of Tier 1 (ISS > 15) and Tier 2 (ISS 9-15) presentations, respectively. Overall use of restraints was worryingly low (36.7%). Not restraining increased the risk of serious RTAs by 8.4 times. Young age, high ISS and low Glasgow Coma Scale score predicted a longer duration of intensive care unit stay. The importance of restraints for motor vehicle passengers or helmets for motorcycle pillion riders and cyclists in reducing morbidity requires emphasis. Suggestions for future prevention and intervention include road safety education, regulation of protective restraints, use of speed enforcement devices and creation of transport policies that minimise kerbside parking.

A Case Study on Speed Behavior Determination Via Average Speed Enforcement at The Akdeniz University Campus Area

Average speed enforcement is a new traffic safety measure that is used increasingly in recent years. The advantage of this enforcement system is that the average speed of drivers can be recorded along a whole section in order to determine whether they obey the speed limits or not. In this study, the speeding behavior and violation behaviors of drivers were quantified in accordance with only the traffic signs and the provided speed limits with no penal sanctions on 11 sections at the Akdeniz University with speed limits of 20, 30 and 50 km/h .Two month average travel speeds of each vehicle that passes from the application sections were measured via mobile average speed enforcement system without announcing to the drivers which were then analyzed via Independent Sample t test .The results of the speed study indicate that they differ on sections with different physical properties according to the preferences of drivers.Low compliance in general to the speed limits indicate non-optimal speed limits. A higher compliance to the speed limits may be ensured by an enforcement measure in the follow-up of the violations.

Introducing the Methodology of Transplanting a New National Speed Management Strategy

Abstract This paper explains the most important methodological steps of introducing a new speed management strategy. The development of a speed monitoring system with a long term effect on the progress of road safety, makes it necessary to identify its strategic goals, main functions and system components. The strategy should investigate current speed management methods, regulation framework of road signs, tendencies represented by statistics, enforcement campaigns, control equipment, and last but not least the penalty system. Assessment of the applied speed enforcement practices and framework should involve the revision of the recently operating institutional, legal and technical framework of speed enforcement structure.

Appraisal of speed-enforcement warning messages among young drivers: Influence of automatic versus human speed enforcement in a known or unknown location

The present study investigated how young drivers assess speed-enforcement warning messages and how these messages affect their motivation to reduce speed. Stemming from deterrence theory (Gibbs, 1985; Homel, 1988) the factors of “celerity”, “certainty”, and “severity” of the sanction were explored as a function of type of speed enforcement (automatic radars vs. police officers) and knowledge of enforcement location (known vs. unknown). Coping factors (e.g., self-efficacy, response cost) from protection motivation theory (PMT; Rogers, 1983) were also considered as critical variables of compliance. Participants (245 students, 51% men) had to choose their speed behavior in a mental simulation of a driving episode on a freeway. As expected, the intention to speed was lower when speed-enforcement warning messages were announced than in the control situation. Threat-certainty ratings were higher when automatic radars were announced, but speeding intentions did not vary according to the automatic versus human type of speed enforcement. Furthermore, automatic radars were perceived as easier to cope with in a maladaptive way (i.e., self-efficacy for avoiding a sanction and adapting speed as a function of speed-enforcement location). An unknown speed-enforcement location was one way of decreasing both women’s and men’s speed. Men calculated a cost-benefit balance to avoid slowing down when they knew the enforcement location. Concerning the predictors of speeding intentions and motivations to reduce speed, self-efficacy ratings for reducing one’s speed proved to be the best PMT predictor.

Speed variation for different drivers, situations, and road geometry: Simulator and survey analysis

ABSTRACTDrivers' speed selection has been a great interest to road safety researchers. In this study, a driving simulator (STISIM) was used to explore drivers' speed choices, and how they are influenced by infrastructure, traffic, risk/benefit, and driver characteristics. Drivers also filled out a stated-preference survey, which included speed selection items and demographic characteristics. The experimental design included four scenarios of a specific risk or benefit to the driver: A daily trip, a higher speed enforcement scenario, a higher crash-risk scenario, and a scenario with high time pressure. The driver sample included 111 drivers from different ages between 20 and 65, with 44% women. The database included 9,768 observations. The largest effect on drivers' speed was under time-saving benefits with an average increase of 10 km/hr. Infrastructure effects included horizontal curves, longitudinal slope changes, and design speed. Age and gender also influenced speed selection. Thus, the most effective measures for speed reduction may be (1) enforcement, (2) design speed, and (3) horizontal curves, in contrast to (1) time-saving benefits and (2) a high average speed of close-by vehicles, which motivated drivers to increase their speed but may be reduced by counteracting policies.

Effect of speed limits at speed transition zones

Speed limits are a common traffic regulation for balancing traffic mobility and safety on roadways. Speed transition zones bear complicated driver behaviours. However, driver behaviours are even more complex when speed transition zones are dynamically created and shifted by variable speed limits (VSLs). Much existing research has estimated long-term driver compliance, evaluated effectiveness of speed enforcement, and attempted to involve compliance into VSL control algorithms. Whereas, limited research provides convincing solutions for representing speed limit effect and estimating real-time driver compliance at speed transition zones. To fill this research gap, this paper analyses field data from two speed transition zones along southbound of 97th Street, Edmonton, Canada. Temporal and spatial variations of speed and driver compliance are investigated in detail using statistical tests. A linear regression is then established to rank the contributions of the selected factors. Finally, some suggestions and guidelines for VSL algorithm design and implementation are proposed.

Addressing Key Concerns Regarding Automated Speed Enforcement via Interactive Survey

Speeding is a public health crisis that accounts for approximately one-third of roadway deaths each year in the United States. One countermeasure with clearly documented efficacy to reduce speed is automated speed enforcement (ASE). Public acceptance, however, has been marginal, with many drivers calling into question its need and legality. This project aimed to measure public rejection of ASE and to provide individualized information strategically to determine if opinions may be shifted more favorably as a result. Statistically significant movement on ASE opinion was achieved after respondents engaged with a tailored survey that addressed their particular concerns about ASE. Almost half (47%) of those who began with a neutral or negative opinion of ASE moved toward a more favorable opinion of it. Those who changed their opinion were more engaged (e.g., considered the opposite of their current stance more fully) and were persuaded by evidence of safety benefits that result from effective speed reduction with ASE deployment.