Vinod Vasudevan

Effectiveness of Media and Enforcement Campaigns in Increasing Seat Belt Usage Rates in a State with a Secondary Seat Belt Law

Objective: In 2005, in terms of seat belt usage rates, Nevada ranked third nationally and first among states with secondary seat belt use enforcement laws in the United States. An effective combination of a media-based education and enforcement campaign helped in this regard. The objective of this article is to document the effectiveness of enforcement and media-based education and outreach campaigns on the seat belt usage rates in Nevada, a state with a secondary seat belt usage law Methods: Observational data on seat belt usage and passenger fatality data are used to evaluate the effectiveness of enforcement campaigns and media-based education and outreach campaigns. Data based on observations of about 40,000 vehicles in each of the years 2003 to 2005 were analyzed. Results: Statistical analyses show that a significant increase in seat belt usage rates among both drivers and passengers for both genders resulted from the accompanying the media and enforcement campaigns. Conclusions: The results from this study indicate that effective and well-planned media/enforcement campaigns can have a significant impact on seat belt usage rates even in a state where the enforcement of seat belt laws can only be as a secondary violation. They validate and expand on findings from other efforts documented in the literature. These results demonstrate that, if coordinated properly, media and enforcement campaigns work very effectively in increasing seat belt usage rates even in states with secondary seat belt laws.

Evaluating Effectiveness of Infrastructure-Based Countermeasures for Pedestrian Safety

This paper summarizes an evaluation of the effectiveness of selected infrastructure-based countermeasures to enhance pedestrian safety. The countermeasures evaluated in this paper were high-visibility crosswalk, median refuge, Danish offset, and pedestrian channelization. The selected countermeasures were deployed at eight locations in the Las Vegas, Nevada, metropolitan area. The evaluations were based on field observations of pedestrian and driver behaviors before and after the installation of the countermeasures. The selected countermeasures were evaluated with measures of effectiveness such as pedestrians who were trapped in the street, pedestrians who looked for vehicles before they began to cross, pedestrians who looked for vehicles before they crossed the second half of the street, pedestrians who were captured (those who modified their path to use the crosswalk but did not go out of their way to do so), pedestrians who were diverted (those who had to go out of their way to use the crosswalk or changed their course of action), drivers who yielded to pedestrians, the distance at which drivers yielded or stopped before the crosswalk, and drivers who blocked the crosswalk. Results showed that a high-visibility crosswalk and a median refuge helped to improve pedestrian as well as driver behavior, whereas a Danish offset increased the proportion of diverted pedestrians. At sites with those countermeasures, the distance at which drivers stopped or yielded for pedestrians before the crosswalk increased. Results based on analysis of data at the site with pedestrian channelization were inconclusive.

Effectiveness of Automatic Pedestrian Detection Device and Smart Lighting for Pedestrian Safety

A summary is given of an evaluation of the effectiveness of an automatic pedestrian detection device and a smart lighting system in improving pedestrian safety. These countermeasures were deployed at a midblock location in the Las Vegas metropolitan area in Nevada. The evaluations are based on field observations of pedestrian and motorist behaviors before and after the installation of the countermeasures. Their effectiveness was evaluated by using the following measures: percentage of pedestrians who looked to their left and right before and while crossing, percentage of pedestrians who changed their course of action, percentage of pedestrians trapped in the middle of the road, percentage of motorists who yielded to pedestrians, distance from the crosswalk at which motorists yielded to pedestrians, and delays. The results show an increase in pedestrians’ observational behavior and an improvement in motorists’ yielding behavior. A reduction in the number of pedestrians trapped in the roadway was also observed. Overall, the installation of the automatic pedestrian detection device and the smart lighting showed positive safety benefits for motorists’ and pedestrians’ behaviors at the test location. The findings from this study could be used to enhance pedestrian safety on arterial roads in other cities with similar demographic characteristics and traffic conditions.

Methods to Prioritize Pedestrian High-Crash Locations and Statistical Analysis of Their Relationships

This paper presents a summary of various methods that can be used to identify pedestrian high-crash locations (HCLs) and statistical evaluations of the relationship between the ranking methods. The indices and methods used to identify and rank pedestrian HCLs include individual methods such as crash indices based on frequency, weighted severity factor, vehicular traffic volume, and pedestrian age group, as well as composite methods such as the sum-of-the-ranks method and the crash score method. The ranks for individual HCLs obtained by these methods may vary, as they are based on different data. There is thus a need to evaluate the statistical relationships between the results obtained by the various methods. Data for 30 pedestrian HCLs in the Las Vegas, Nevada, metropolitan area were used to illustrate the methods and conduct statistical analyses. The results indicated that the rankings based on the individual methods were strongly correlated to the rankings from the composite methods, as were the rankings between the composite methods. The results also indicated that the rankings based on individual methods were correlated among themselves, although this correlation was not as strong. Furthermore, when only the top few highest-ranked HCLs were considered, their ranks were strongly correlated, regardless of the method chosen. Although any of the methods could be used to identify pedestrian HCLs, use of the simple frequency- or weighted frequency-based methods would be adequate as a first step.

Impacts of Energy Regulations and Vehicular Technologies on Fuel Tax Revenues

Various energy regulations including corporate average fuel economy (CAFE) are forcing auto manufacturers and auto distributors to improve the fuel efficiency of vehicles significantly over the next decade. Conversely, improved automotive technologies and higher gasoline fuel prices enable better alternative-fuel vehicles (AFV), including hybrid vehicles (HV) and electric cars. This research evaluates the impacts of CAFE regulations in automobile and light truck fleet fuel economies, and effects of HV and AFV in the fleet, on gasoline-tax-based revenues. The new sales survivability (NSS) model, along with new vehicle sales data and vehicle survivability data from 1980 to 2005, were used to estimate the fleet mix, vehicle miles traveled (VMT) by fleet mix, and revenue projections through the year 2025. Five scenarios were considered to analyze the impacts of CAFE regulations and introduction of HV and AFV on fuel consumption and fuel-tax-based revenues for highway revenues. The results show that the CAFE regulation alone is expected to reduce the fuel-tax-based revenue by more than 21% in the year 2025. Similarly, the introduction of HV and AFV along with CAFE regulations is expected to reduce fuel-tax-based revenues by more than 31 and 37%, respectively, in the year 2025. This paper shows the significance of considering the effects of new regulations and technological improvements in estimating future fuel-based revenues. The revenue estimated in this paper is much lower than the estimates developed by previous studies. This shows that modifications to the existing system of highway financing would be required much earlier than anticipated.

A Model to Estimate Passenger Vehicle Fleet Composition, Vehicle Miles Traveled, and Fuel Consumption

A significant portion of funds in the United States for road maintenance and improvement are the levy of a fuel tax per gallon of fuel sold. The government mandated improvements in fuel efficiency of vehicles and the greater proportion of hybrid or nongasoline-powered vehicles expected to be used for passenger transportation are anticipated to adversely affect such revenues. In this study, readily available public domain data on new vehicle sales and survivability data are used to develop estimates of the future fleet composition by specific vehicle categories, vehicle miles traveled by the vehicle category, and fuel consumption by the vehicle category. It is then used to develop estimates. The model takes into consideration the emerging classes of hybrid and alternative fuel vehicles, which were not adequately captured in the historical data. This methodology could be used to support policy and operations analysis related to highway financing and infrastructure management.

Disaggregate Model for Vehicle Ownership Behavior of Indian Households

For a highly populated developing country, such as India, that imports a significant share of its petroleum, it is necessary to understand the private vehicle ownership behavior of the countrys households to design policies fostering sustainable development of the countrys transportation sector. The study addresses this concern by developing an all-India disaggregate model for private vehicle ownership behavior with the use of data of the Consumer Expenditure Survey conducted by the National Sample Survey Office of the government of India from July 2009 to June 2010. An appropriate proxy variable for economic standard has been designed as an explanatory variable in the vehicle ownership model. The study evaluates the effect of various socioeconomic factors on the private vehicle ownership behavior of Indian households after testing the relevance of each of the factors. It also confirms that economic standard and household size are two important determinants of private vehicle ownership behavior.

IDENTIFICATION OF HIGH PEDESTRIAN CRASH SITES AND SELECTION OF COUNTERMEASURES FOR THE LAS VEGAS METROPOLITAN AREA

This paper presents a model and evaluation of the effectiveness of safety improvement projects funded under the Hazard Elimination Program (HEP) and the Highway-Rail Grade Crossings Program (HRGCP) at the national level based on the crash, cost and traffic data of projects implemented from 1995 to 2000, which were obtained from the states. Major findings from the study include: (1) At the national level, projects implemented under the HEP showed a 28.6 percent reduction in the number of crashes, a 61.6 percent reduction in fatal crashes, and a 17.1 percent reduction in injury crashes; (2) Projects implemented under the HRGCP resulted in a 21.4 percent reduction in the number of crashes, a 100 percent reduction in fatal crashes, and a 31.3 percent reduction in injury crashes; (3) The benefit-cost ratio was 11.3 for projects implemented under the HEP, and 8.5 for projects implemented under the HRGCP; and (4) Of the various improvement types, the implementation of illumination projects showed the highest benefit-cost ratio.This paper presents a Geographic Information System (GIS) based methodology to identify high pedestrian crash sites ad then select safety countermeasures based on casual factors. The methodology to select high crash sites includes identifying the problem area, the high risk zones and then the high crash sites. Two types of crash indices were used to rank high risk zones. They are based on the number of pedestrian crashes in the vicinity of the zone by severity and length of the zone. Results obtained by applying the methodology in the Las Vegas metropolitan area are discussed in this paper.

FIELD DATA COLLECTION AND ANALYSES TO SUPPORT THE SELECTION OF PEDESTRIAN SAFETY COUNTERMEASURES IN LAS VEGAS

Crash reduction factors (CRFs) are used in highway safety studies to estimate how far a countermeasure may potentially reduce the number of crashes on a given roadway location. As with most states in the United States, Florida developed its CRFs based on the before-and-after approach, which requires the use of crash records and implemented safety improvement projects. The Florida Department of Transportation (FDOT) did not have a central database for safety improvement projects. Consequently, historical data for improvement projects were maintained separately at various district offices in various formats and were not easily accessible for the purpose of statewide CFR development. This paper describes an effort by FDOT to develop a user-friendly database system for the systematic maintenance of a new standard set of safety improvement projects and for continued update of CRFs as new data become available. Currently, no similar system is known to exist. It may serve as a prototype by states planning to develop a similar system that it tailored to their improvement projects and crash records.

Design and Evaluation of K-Pass: A Bicycle-Friendly Modification of Speed Bumps

Traffic safety is a major concern across the world. Since speed is a major cause of traffic crashes, various traffic calming measures are used to enhance the safety of the road users in urban areas. Speed humps and bumps are the most widely used traffic calming devices. As a considerable number of bicyclists use the road along with motorized users, it is important to consider them while deploying any traffic calming devices. Studies have shown that bicyclists experience significantly larger discomfort as compared to motorized vehicles while passing over speed humps. In this study, a modification has been proposed to enhance riding comfort of bicyclists without compromising the traffic calming attribute of a speed bump. This modification is named “K-pass.” Analysis of data collected before and after the modification justifies the effectiveness in reducing the discomfort of bicyclists. Over a period of eight months, 70% of the bicyclists chose to use K-pass. Data also revealed that a high proportion of motorized two-wheeler users also used the K-pass at reduced speeds. It is expected that the K-pass will be a useful modification to the existing speed humps and speed bumps in areas where bicycle usage is expected.