Safety Aspects of Using Vehicle Hazard Warning Lights: Volume 1. Executive Summary

DOT-FH-11-9385This report describes a series of experiments that were conducted to examine the effectiveness of four-way flashers. Both the disabled vehicle situation and the slow-moving vehicle situation were examined at two- and four-lane locations under both daylight and nighttime conditions. The disabled vehicle tests involved parking a test vehicle (either a car or a tractor-trailer) at the side of the road and monitoring the behavior of drivers. The slow-moving vehicle tests involved introducing a staged slow-moving vehicle (either a car or a tractor-trailer) into the traffic stream and observing the overtaking vehicles. At the disabled vehicle, red and amber four-way flashers as well as flares, reflectorized triangles, headlights, and other situational factors were evaluated. For the slow-moving vehicle tests, the effects of red and amber flashers as well as a 30 and 40 mph (48.3 and 64.4 kph) slow-moving vehicle were examined. For both the disabled and the slow-moving vehicle situations, it was found that four-way flashers are effective at reducing the inherent danger. In the disabled situation, it was found that approaching motorists slow down sooner and slow down more when flashers are displayed. In the slow-moving situation, it was found that drivers of overtaking vehicles approach more cautiously and pass more carefully. In both situations flashers increase the awareness of the drivers of overtaking vehicles

Safety Aspects of Using Vehicle Hazard Warning Lights: Volume 2. Final Report

DOT-FH-11-9385This report describes a series of experiments that were conducted to examine the effectiveness of four-way flashers. Both the disabled vehicle situation and the slow-moving vehicle situation were examined at two- and four-lane locations under both daylight and nighttime conditions. The disabled vehicle tests involved parking a test vehicle (either a car or a tractor-trailer) at the side of the road and monitoring the behavior of drivers. The slow-moving vehicle tests involved introducing a staged slow-moving vehicle (either a car or a tractor-trailer) into the traffic stream and observing the overtaking vehicles. At the disabled vehicle, red and amber four-way flashers as well as flares, reflectorized triangles, headlights, and other situational factors were evaluated. For the slow-moving vehicle tests, the effects of red and amber flashers as well as a 30 and 40 mph (48.3 and 64.4 kph) slow-moving vehicle were examined. For both the disabled and the slow-moving vehicle situations, it was found that four-way flashers are effective at reducing the inherent danger. In the disabled situation, it was found that approaching motorists slow down sooner and slow down more when flashers are displayed. In the slow-moving situation, it was found that drivers of overtaking vehicles approach more cautiously and pass more carefully. In both situations flashers increase the awareness of the drivers of overtaking vehicles

Pedestrian Accidents Occurring on Freeways: An Investigation of Causative Factors, Accident Data Collection and Analysis. Vol. I. Executive Summary

DOT-HS-355-3-7l8The objective of this study was to collect and analyze data on freeway pedestrian accidents. Data on 236 accidents involving pedestrians struck on limited-access highways were collected. The data included behavioral sequence items, site characteristic items, identification items, pedestrian factors, driver factors and vehicle factors. The accident investigations were intended to identify the precipitating and predisposing factors in each accident. The data reduction and data analysis phase resulted in the identification of a number of characteristic accident situations or accident types. Although 14 different accident types were identified, the most frequent types accounted for nearly 60% of the accidents. Countermeasures intended to impact on each of the accident types are discussed. The relatively infrequent occurrences (less than 1,000 nationwide annually) and the varied causal factors involved (suicide, alcohol, poor weather, disabled vehicles) suggest that countermeasure implementation be very carefully considered on a site-by-site basis. This report is the first in a series

Urban Intersection Improvements for Pedestrian Safety Volume 1. Executive Summary

DOT-FH-11-8533This purpose of the study was to identify problems associated with pedestrian-vehicle interactions at intersections, develop countermeasure concepts that would reduce these problems, and evaluate the most desirable countermeasures to determine their effectiveness. As an additional phase, Federal Highway Administration included a study to evaluate alternatives to full signalization at pedestrian crossings. The study was divided into three phases: Phase I was reported in Volume II, Identification of Safety and Operational Problems and was directed at identifying and defining the safety and operational problems associated with the interaction of pedestrians and vehicles at intersections. Phase II was divided into two tasks. Task A conducted research dealing with signal timing for the pedestrian. Task B was directed towards pedestrian signal display and operation research. Task A reported in Volume III, Signal Timing for the Pedestrian was directed at making recommendations concerning improvements in the timing of pedestrian traffic signals, both to maximize safety and to minimize delay. The report was divided into three sections: 1. Timing for a Combined Pedestrian-Vehicle Interval. 2. Alternative Phasing Schemes. 3. Other Areas of Pedestrian Signal Research. Task B was reported in Volume IV. Pedestrian Signal Displays and Operation was directed at evaluating pedestrian signal displays and operations. The study was divided into three parts: 1. Lunar vs. Clear White "WALK" Lens Study. 2. Word Message and Operation Study. 3. Symbol Message Study. Phase III reported in Volume V, Evaluation of Alternatives to Full Signalization at Pedestrian Crossings, was to develop traffic control devices that could be used as alternatives to full signalization at pedestrian crossings that are located at intersections. These traffic control devices were evaluated at the intersection of an arterial street with a low-volume residential street where adequate gaps in the traffic steam do not exist to allow pedestrians to cross the arterial street safely. The study was divided into two parts: identification of alternative pedestrian crossing designs, and field evaluations. Other volumes include: Volume II--Identification of Safety and Operational Problems at Intersections. Volume III--Signal Timing for the Pedestrian. Volume IV--Pedestrian Signal Displays and Operation. Volume V--Evaluation of Alternatives to Full Signalization at Pedestrian Crossings

Urban Intersection Improvements for Pedestrian Safety Volume IV. Pedestrian Signal Displays and Operation

DOT-FH-11-8533This report summarizes that portion of the research dealing with pedestrian signal displays and operation which was completed in Phase II of the three-phase project on urban intersection improvements for pedestrian safety. Three evaluation studies were conducted. The first study was a controlled experiment to determine what difference existed between "lunar" and "clear" white WALK lenses in pedestrian signals. The findings indicated that "clear" white had better target value, but that "lunar" white was more readable for three of the four lighting conditions tested. The second study consisted of three experiments, two of which dealt with the clearance interval display, while the third evaluated flashing versus steady WALK. Of the two clearance displays tested, i.e., steady DONT WALK and steady DONT START, neither showed a significant improvement over the standard flashing DONT WALK clearance indication. Flashing WALK was found not to be effective as a means of warning pedestrians of turning vehicles. The third study evaluated the concept of using symbolic pedestrian displays in place of the current word message display. The hand-walking man symbol was found to show a significant improvement over the standard WALK-DONT WALK display. Orange and white were found to be better colors for pedestrian signal indications than red and green

Urban Intersection Improvements for Pedestrian Safety Volume V. Evaluation of Alternatives to Full Signalization at Pedestrian Crossings

DOT-FH-11-8533This report summarizes the research completed in the third phase of a three-phase project. This phase was directed at identifying and evaluating alternatives to full signalization at pedestrian crossings. These pedestrian crossings are located at the intersection of a high-volume arterial street and a low-volume residential street. The selection of alternatives could not include grade-separated pedestrian structures, midblock crossings, or full signalization. Five alternatives were selected for field evaluation with the following traffic devices on the major and minor streets, respectively: Sign and Stop Sign, Flashing Yellow Signal and Flashing Red Beacon, Flashing Green Signal and Stop Sign, (Sg-44) Signal and Stop Sign, and Crossing Guard with stop signs on the residential street. The report compares the five school-pedestrian crossing designs with their fully signalized control sites discussing their relative advantages and disadvantages. Further comparisons were made between the various alternatives. The Crossing Guard, (Sg-44) Signal and Stop Sign, and Flashing Green Signal and Stop Sign were determined to have operating characteristics significantly more desirable than those of a fully signalized intersection. Of these, the Crossing Guard and the Signal and Stop Sign were recommended as alternatives to full signalization at pedestrian crossings. The report includes guidelines for the selection of the alternatives and the appropriate site criteria

Urban Intersection Improvements for Pedestrian Safety Volume III. Signal Timing for the Pedestrian

DOT-FH-11-8533This report presents the final results of the signal timing element of the FHWA research project "Urban Intersection Improvements for Pedestrian Safety." The report discusses the research which was conducted, and recommends improvements in the timing of pedestrian traffic signals both to maximize safety and to minimize delay. Specifically, the elements covered in this volume include the following: Chapter II--Timing for a Combined Pedestrian--Vehicular Interval. This includes discussions of minimum WALK time, minimum clearance interval, and allocation of excess pedestrian time. Chapter III--Alternative Phasing Schemes. This includes an analysis of early and late release of pedestrians with respect to vehicles, scramble pedestrian timing, and signal phasing for the partial crossing of wide, channelized streets. Chapter IV--Other Areas of Pedestrian Signal Research, including time-of-day adjustments of pedestrian signal timing, application of correction factors to the Highway Capacity Manual based on vehicle and pedestrian activity levels, and general observations on pedestrian flow characteristics

Urban Intersection Improvements for Pedestrian Safety Volume II. Identification of Safety and Operational Problems at Intersections

DOT-FH-11-8533This report summarizes the research completed in the first phase of a three-phase project. This phase was directed at identifying and defining the safety and operational problems associated with the interaction of pedestrians and vehicles at intersections. Both signalized nonsignalized intersections were investigated. Four sources of information were used to define problems and uncover implications for countermeasure concepts. These sources included: accident data, expert opinion, behavioral observations, conceptual investigations. The significant findings from all four sources are presented in terms of the following categories: undesirable pedestrian and vehicle interactions; undesirable pedestrian and/or driver behaviors; undesirable intersection characteristics; and undesirable traffic control device characteristics. Several countermeasure concepts that address some of the above problems were identified. The information required in order to design the specific countermeasures is documented in the body of the report. Likewise, the means for evaluating the effectiveness of the specific countermeasures have been developed and are reported