Field Evaluation of the PAS III Passive Alcohol Sensor

Passive alcohol sensors (PAS) are screening devices designed to sample nonintrusively the ambient air around a driver's mouth to determine the presence of alcohol. Studies have shown that PAS devices can aid police officers in the identification of unpaired drivers, particularly at sobriety checkpoints. Data from a 1996 nationwide survey, in which 5,392 drivers were evaluated for alcohol using both the PAS III (a passive sensor housed in a flashlight) and evidential breath test devices, have allowed the determination of appropriate criteria at various blood alcohol concentrations (BAC) for detecting impaired drivers in the field. Using the appropriate criteria, the PAS III can identify about 75% of the drivers with BACs at or above 0.10%, and 70% at or above 0.08%. This is a vast improvement over the 40-50% detection rate currently achieved by police officers at checkpoints not using sensors. Using the PAS III few drivers would be identified inappropriately. At the criterion recommended for detecting BACs at or above 0.08%, about 14% of drivers with BACs of 0.02-0.05% would be incorrectly identified as having a higher BAC. Field studies have shown that when police officers rely on observation alone about 20% of drivers with low BACs are detained for further evaluation. More widespread use of passive sensors by police officers would aid in the detection of drinking drivers. Sensors also could provide an additional deterrent to the general public if they believe that when stopped by the police after drinking they will be detained for further evaluation.     

Age Dependence of Female to Male Fatality Risk in the Same Crash: An Independent Reexamination

A 1988 study reported that females are more likely than males to be killed by the same physical insult. This was determined by analyzing 1975–1983 data. The present study revisits this question using 123,678 fatalities from 1984–1996 data. As none of these data contributed to the earlier study, the present investigation is therefore independent of the earlier one. Female to male fatality risk ratios are calculated for 14 categories of vehicle occupants, including six light truck occupants (belted and unbelted drivers and right front passengers, and unbelted left and right rear passengers). The earlier study did not include light trucks. Close agreement is found between the results of the present and prior studies, thus solidifying the interpretation that findings are of a general nature and not dependent on specific data sets. Except at ages less than about 10 years, or older than about 55, females are more likely to be killed than males. While obtained using traffic data, the results are interpreted to reflect fundamental differences in human physiological response to blunt trauma in general, and are expected to apply to blunt trauma from falls, being struck by objects, etc.     

The effectiveness of reducing illegal blood alcohol concentration (BAC) limits for driving: evidence for lowering the limit to .05 BAC

PURPOSE: This scientific review provides a summary of the evidence regarding the benefits of reducing the illegal blood alcohol concentration (BAC) limit for driving and providing a case for enacting a .05 BAC limit. RESULTS: Fourteen independent studies in the United States indicate that lowering the illegal BAC limit from .10 to .08 has resulted in 5-16% reductions in alcohol-related crashes, fatalities, or injuries. However, the illegal limit is .05 BAC in numerous countries around the world. Several studies indicate that lowering the illegal per se limit from .08 to .05 BAC also reduces alcohol-related fatalities. Laboratory studies indicate that impairment in critical driving functions begins at low BACs and that most subjects are significantly impaired at .05 BAC. The relative risk of being involved in a fatal crash as a driver is 4 to 10 times greater for drivers with BACs between .05 and .07 compared to drivers with .00 BACs. SUMMARY: There is strong evidence in the literature that lowering the BAC limit from .10 to .08 is effective, that lowering the BAC limit from .08 to .05 is effective, and that lowering the BAC limit for youth to .02 or lower is effective. These law changes serve as a general deterrent to drinking and driving and ultimately save lives. IMPACT ON INDUSTRY: This critical review supports the adoption of lower illegal BAC limits for driving.     

农村摩托车驾驶员驾驶行为调查分析——以山东莒南为例

为探究农村摩托车驾驶员常见的不安全驾驶行为及农村摩托车事故多发的原因,采用问卷调查的方法,从人、车、交通管理等几个角度对我国山东农村地区的480名摩托车驾驶员进行了入户问卷调查.通过SPSS17.0软件对收集的数据进行处理,重点对驾驶员的驾驶行为进行分析,结果显示在403名驾驶员中仅有60(14.9%)人拥有驾照、74...     

Residual road departure crashes after full deployment of LDW and LDP systems

Abstract

Objective: Road departures are one of the most severe crash modes in the United States. To help reduce this risk, vehicles are being introduced in the United States with lane departure warning (LDW) systems, which warn the driver of a departure, and lane departure prevention (LDP) systems, which assist the driver in steering back to the roadway. Previous studies have estimated that LDW/LDP systems may prevent one third of drift-out-of-lane road departure crashes. This study investigates the crashes that were not prevented, to potentially set research priorities for next-generation road departure prevention systems.

Methods: The event data recorder (EDR) data from 128 road departure crashes in the National Automotive Sampling System Crashworthiness Data System (NASS-CDS) from 2011 to 2015 were mapped onto the vehicle trajectory and simulated with LDW/LDP to assess the potential for crash avoidance. The model predicted that 63–83% of single-vehicle road departure crashes may not be prevented by an LDW system and 49% may not be prevented by an LDP system.

Results and Conclusions: For LDP systems, which were assumed to have zero latency, no crashes were avoided if the time-to-collision (TTC) from lane crossing to impact was less than 0.55?s. Obstacles such as guardrails and traffic barriers, which tend to be very close to the road, were more common among the remaining crashes. The study shows that LDW/LDP systems are limited by two factors, driver reaction time and TTC to the roadside object. Thus, earlier driver response and longer TTC may help in these situations.     

Trends in motor vehicle crash mortality in Europe, 1980-2007

Recent trends (1980-2007) in mortality from road traffic crashes in European countries, and, for comparative purposes, in the USA and Japan were reviewed. Data came from the World Health Organisation database. Age-standardised rates, at all ages and at 15-24, 25-64, ?65 years, were computed. Joinpoint regression analyses to evaluate significant changes in trends were performed. In the European Union as a whole rates declined from 20.2 in 1987 to 13.5/100,000 in 2007 in men, and from 6.3 to 3.7/100,000 in women; European Union rates remained lower than USA, but higher than Japanese ones. In 2007, the highest male rates were in Lithuania (36.7/100,000), the Russian Federation (35.2), Ukraine (29.8), and Latvia (28.5), and the lowest ones in the Netherlands (6.2) and Sweden (6.9); the highest female rates were in the Russian Federation (11.3), Lithuania (9.7), Belarus, Latvia, and Ukraine (around 8), and the lowest ones in Switzerland (1.7), the UK, and Nordic countries (around 2). Mortality from motor vehicle crashes declined in northern and western European countries and - though to a lesser extent - in southern European countries, too. Mortality trends were also favourable in the Czech Republic and Poland since the mid 1990’s, whereas they were still upwards in Romania and the Russian Federation. No trend was observed in Hungary and Ukraine. Trends were consistent in various age groups considered. Thus, additional urgent and integrated intervention is required to prevent avoidable deaths from motor vehicle crashes, particularly in selected central and eastern European countries.     

Severity of motorcycle crashes in Dar es Salaam,Tanzania

Objective: Motorcycles are a common mode of transportation in low- and middle-income countries. Tanzania, in particular, has experienced an increased use of motorcycles in the last decade. In Dar es Salaam, motorcycles provide door-to-door travel and often operate where more conventional services are uneconomical or physically impossible to maneuver. Although motorcycles play a crucial role in improving mobility in the city, they have several safety issues. This study focuses on identifying factors influencing the severity of motorcycle crashes.

Method: A multinomial logit analysis was conducted to identify factors influencing the severity of motorcycle crashes in Dar es Salaam, Tanzania. The severity categories were fatal, severe injury, minor injury, and property damage only (PDO). The analysis was based on a total of 784 motorcycle crashes that occurred from 2013 to 2016.

Results: The following factors were found to increase the probability of a fatality: Speeding, driving under the influence, head-on impact, presence of horizontal curves, reckless riding, off-peak hours, violations, and riding without a helmet. The results indicate that crashes occurring on weekdays, during peak hours, at intersections, involving a rear-end impact, in daylight, on street roads, and under clear weather conditions decrease the probability of a fatality. However, minor injury and PDO crashes were found to be associated with crashes occurring during peak hours, at intersections, and on street roads, as well as failure to yield right-of-way.

Conclusions: Several countermeasures are recommended based on the study findings. The recommended countermeasures focus on the holistic safety improvement strategies constituting the three Es of highway safety, namely, engineering, education, and enforcement.     

Influence of pedestrian age and gender on spatial and temporal distribution of pedestrian crashes

Objectives: Every year, about 1.24 million people are killed in traffic crashes worldwide and more than 22% of these deaths are pedestrians. Therefore, pedestrian safety has become a significant traffic safety issue worldwide. In order to develop effective and targeted safety programs, the location- and time-specific influences on vehicle–pedestrian crashes must be assessed. The main purpose of this research is to explore the influence of pedestrian age and gender on the temporal and spatial distribution of vehicle–pedestrian crashes to identify the hotspots and hot times.

Methods: Data for all vehicle–pedestrian crashes on public roadways in the Melbourne metropolitan area from 2004 to 2013 are used in this research. Spatial autocorrelation is applied in examining the vehicle–pedestrian crashes in geographic information systems (GIS) to identify any dependency between time and location of these crashes. Spider plots and kernel density estimation (KDE) are then used to determine the temporal and spatial patterns of vehicle–pedestrian crashes for different age groups and genders.

Results: Temporal analysis shows that pedestrian age has a significant influence on the temporal distribution of vehicle–pedestrian crashes. Furthermore, men and women have different crash patterns. In addition, results of the spatial analysis shows that areas with high risk of vehicle–pedestrian crashes can vary during different times of the day for different age groups and genders. For example, for those between ages 18 and 65, most vehicle–pedestrian crashes occur in the central business district (CBD) during the day, but between 7:00 p.m. and 6:00 a.m., crashes among this age group occur mostly around hotels, clubs, and bars.

Conclusions: This research reveals that temporal and spatial distributions of vehicle–pedestrian crashes vary for different pedestrian age groups and genders. Therefore, specific safety measures should be in place during high crash times at different locations for different age groups and genders to increase the effectiveness of the countermeasures in preventing and reducing vehicle–pedestrian crashes.