Assessing the impact of three intersection treatments on bicyclist safety using a bicycling simulator.

Bicyclist safety at urban intersections is a critical element for encouraging an increase in bicycle commuting. With cyclist injury and fatality rates rising due to collisions with vehicles at signalized intersections, increasing the safety of riders continues to be an important consideration when promoting this mode of transportation. Previous research has addressed crash causality and helped to develop several roadway treatments to improve bicyclist safety, but little has been done to compare and contrast the benefits of the various treatment types. This bicycling simulator study examined the impacts of three different intersection treatments (i.e., bike box, mixing zone, and bicycle signals) to better understand their influence on bicyclists' comfort, levels of stress, and riding behaviors. This improved understanding allowed researchers to make recommendations for which of the three designs proved to be most effective for reducing the risk of vehicle-bicycle collisions at signalized intersections. Forty participants successfully completed the study by responding to twenty-four scenarios while riding in the Oregon State University Bicycling Simulator. Time-space measurements revealed that the mixing zone treatment correlated with the most unpredictable riding behaviors. Analysis of the participants' eye-movements revealed a lower rate of recognizing the conflict vehicle when traversing the bicycle signal treatments. Galvanic Skin Response measurements were used to measure participants stress levels but found no statistically significant results, although it was found that the mixing zone elicited slightly larger stress responses. Researchers found the bike box design to be the most versatile, providing a balance of increased safety while also requiring the participant to perceive potential danger and be ready to respond accordingly. The results of this research can provide a better understanding of how to best implement these intersection treatments to increase bicyclists' safety at signalized intersections.

Analysis of factors affecting injury severity for riders or occupants of all-terrain vehicles and golf carts involved in police-reported crashes.

In recent years, the popularity of all-terrain vehicles (ATVs) in the United States (US) has increased, and the number of ATV driver and passenger deaths have also increased substantially in the last few decades. Riders or occupants of ATVs as well as golf carts are particularly vulnerable to injury, not only due to the lack of protection and safety equipment offered by their vehicles, but also the propensity for ejection in the event of a crash. Given the vulnerability of these road users, it's critical to understand factors which may affect injury severity to plan effective countermeasures aimed at reducing these injuries and fatalities. To better understand factors affecting the injury severity of ATV and golf cart riders or occupants involved in police-reported crashes, this study presents an analysis using six years of crash data from the US state of Arizona. Over the analysis period, there were 1769 drivers/passengers of these vehicle types involved in police-reported crashes. Of these occupants/riders, 67.7% were injured or killed as a result of the crash; a proportion significantly higher than police-reported crashes involving most other vehicle types, exhibiting the need to examine factors leading to these injuries and fatalities. In order to analyse factors affecting the injury severity of ATV and golf cart occupants/riders, a random parameters (RP) ordered logit statistical model was developed, which was most appropriate given the ordered nature of injury-severity data. Several person- vehicle- roadway- and environmental-related variables were found to significantly affect the injury severity of riders or occupants of ATVs and golf carts. Given the vulnerability of these road users, it's important for transportation agencies to explore effective countermeasures aimed at reducing the severity of crashes involving these vehicle types. The results of this study provide important insights which can assist in developing effective engineering-, enforcement-, education, or policy-related countermeasures.