Aaron Cole SCI 201 Prof. Amy Larson 28. November 2011 ABSTRACT Red-Light Behavior between Motor Vehicles and Bicycles By: Aaron Cole, Stephanie Benston, Philip Cohoe, and Stacy Harris This study looked at the behavior of bicyclists and motor vehicle operators in regards to compliance at red lights. Three intersections around the campus of Portland State University were chosen due to high amounts of traffic, the proximity to large amounts of pedestrians, and the presence of a bike lane or cycle track. Data was recorded at various times between 7 November 2011 and 12 November 2011. Approximately 502 vehicles were recorded, 497 motor vehicles and 99 bicycles. Overall, 56% of bicyclists refused to obey a red light compared to 7% of motor vehicles. At each intersection, regardless of the time, bicycles consistently ran red lights more than motor vehicles. The findings suggest that bicyclists are more likely to run a red light than motor vehicle operators. Keywords: bicyclists, motor vehicles, red-light laws, traffic laws, bicyclist attitudes and behavior INTRODUCTION The city of Portland, Oregon has a large number of commuters who choose to ride a bicycle instead of a motor vehicle. With this come challenges to increase the safety of motorists, bicyclists, and pedestrians. The state of Oregon has taken measures in increasing bicycle awareness and safety, such as the creation of safer bicycle lanes (Monsere, McNeil and Dill, 2011) and a Share the Road campaign that includes custom license plates (Oregon Department of Transportation, 2011). Yet despite these efforts, a gap exists in the behavior of motor vehicle operators and bicyclists; compliance at a red light. In depth studies have been undertaken to look at the various characteristics and factors behind cyclists running red lights (Johnson et al, 2010) while others have ascertained the behavior and challenges of bicyclists in their daily commute (Royal and Miller-Steiger, 2008). While these studies have been incredibly detailed, in the end it boils down to one key aspect of every vehicle operator: integrity. The majority of children in grade school have been shown to know they are required to stop at red lights on a bicycle (Kimmel and Nagel, 1990), yet many adults choose not to obey the law and risk injury (Chong, 2010) or even death (Lee, 2011) (Collette, 2010) in the event of a collision with a pedestrian. While motor vehicles are required to be registered and the operators licensed, the same is not required of bicyclists. For our hypothesis we believed that bicycles would run more red lights than motor vehicles. The aim of our study was to establish that there was a distinction in the behavior between motorists and bicyclists at red lights. With these findings, newer safety regulations or cyclist training efforts could be established to prevent injury or death among the population, in addition to improving the public image of bicyclists in the city of Portland. [ 1]
METHODS Our study was conducted over the course of six days, from 7 November 2011 to 12 November 2011. We chose three locations based on their proximity to the Portland State University campus and their high volume of vehicle and pedestrian traffic: SW 6 th and Mill, SW Broadway and Montgomery, and SW Broadway and Harrison. Of those three locations, we only analyzed the traffic going down the main lanes of 6 th and Broadway, as we perceived the total traffic to be greater than the side streets of Harrison, Montgomery, and Mill. Times were selected for both the morning and afternoon when traffic was likely to be high. Our subjects included all motorists and bicyclists who were approaching a red light. Data was collected by counting only those vehicles that were faced with the decision to stop or run a red light; the vehicles behind a stopped vehicle would not be counted as they were not presented a choice. Our data was recorded in a notebook and then transferred to an excel spreadsheet upon completion of the observational period. Two of the three intersections were chosen because of their unique characteristic: the Cycle Track. While the cycle track is a bicycle lane, it is separated from the flow of traffic by a parking lane offering a safer riding environment. Both Broadway and Montgomery and Broadway and Harrison were chosen because of the cycle track and the lack of vehicle traffic approaching from the right. 6 th and Mill was chosen due to its lack of a bicycle lane, forcing the bicyclist to share the road with motorists. Both motor vehicles and bicycles were subjected to the same laws in accordance with ORS 811.028 and ORS 814.400 (Oregon State Legislature, 2009). Bicycles would be subject to the same laws as a motor vehicle per ORS 814.400. In accordance with ORS 811.028, bicycles would be counted as running a red light if they failed to stop or remain stopped for the duration of the light. For the two intersections that featured a cycle track, bicycles were not counted if they made a right-hand turn into campus. Bicycles and cars who made a left-hand turn down a two-lane street were counted as running a red light as they were in violation of the law. If a motor vehicle or bicycle ran through a yellow light that turned red mid-way, they were not counted. In doing so, only vehicles that knowingly saw a red light and chose to either stop or continue on were counted to ensure accuracy and consistency. The Chi-Square test was used for statistical analysis, with the results allowing us to reject the null hypothesis. RESULTS Table 1 Number of motor vehicles and bicycles that ran or stopped at red lights. Stopped at Red Type of Vehicle Lights Ran Red Lights Total M otor Vehicles 461 36 497 Bicycles 41 58 99 Tot al 502 94 596 [ 2]
Fig. 1 The numbers for all vehicles and the behavior at red lights is provided in Table 1. Overall, motor vehicles were more likely to stop for red lights than bicycles. While the total number of motor vehicles is greater than the total bicycles counted, bicycles ran more red lights than motor vehicles. The data shown in figure 1 shows that 58% of bicycles ran red lights compared to only 7% of motor vehicles at all three intersections combined. Fig. 2 The data in figure 2 shows the data collected from Broadway and Harrison over the course of three days. Between the hours of 0730 and 0830 the data shows that motorists were more willing to obey traffic laws than bicycles. During the afternoon, a greater number of motor vehicles ran red lights while a larger percentage of bicycles obeyed the law compared to the morning observations. However, bicycles represented the greater percentage of vehicles that ran red lights. Fig. 3 The data in figure 3 represents the vehicles that stopped or ran red lights at the intersection of 6 th and Mill. The data shows a greater number of bicycles that ran red lights on November 8 th, 2011 compared to the low number of motor vehicles. The data on November 9 th, 2011 saw a greater number of motor vehicles running red lights, although only three bicycles were counted with one of those running the red light. The morning of November 11 th, 2011 saw an improvement from the observation on the 8 th, with only 1 motor vehicle and 5 bicycles running red lights compared to 3 motor vehicles and 8 bicycles. Fig. 4 The data represented in figure 4 represents the data collected from Broadway and Montgomery. During both November 10 th, 2011 and November 12 th, 2011 only 2 motor vehicles ran red lights on each day. Bicycles varied in results, with 12 bicycles running reds on the 10th compared to only 2 on the 12 th. Fig. 5 Finally, the data in figure 5 represents the different findings between the intersections that contained a cycle track compared to those who are riding on the street in the absence of a bicycle lane. Motor vehicles showed similar results for both conditions, while bicyclist behavior differed greatly depending on the road type. 14 bicycles ran red lights while 22 stopped while riding on the street compared to 44 bicycles running red lights and 19 stopped while riding in a cycle track. [ 3]
DISCUSSION The data clearly shows that despite the greater ratio of motor vehicles compared to bicycles, bicyclists were more likely to run red lights. A study among school children showed that even without any prior safety training, 74% of children knew to stop at red lights compared to 90% who had training (Kimmel and Nagel, 1990). Of the adult riders we observed, only 41% of bicycles stopped at red lights. As the locations we chose were ones that have a high amount of pedestrian traffic, this poses a potential safety hazard to pedestrians who are crossing the street. The US Department of Transportation conducted a study in 2008 that analyzed the behavior of bicyclists, showing that their greatest threat on the road was a motor vehicle (Royal and Miller-Steiger, 2008). While a collision with a motor vehicle is a major risk to bicyclists, pedestrians too can be a concern. While pedestrian-bicycle collisions are not as common as motor vehicle-bicycle collisions, they are a considerable risk, with hospitalization for injuries among those hit a possibility (Chong, 2010). Furthermore, a risk of death among those hit is a potential outcome of a pedestrian-bicycle collision. In August 2011, a woman in San Francisco died as a result of injuries sustained from a pedestrian-bicycle collision at a crosswalk in which a bicyclist ran a red light (Lee, 2011). A key difference in behavior was the presence of a cycle track along Broadway. While there were less total bicycles observed on the street compared to the cycle track, the riders were less likely to run the red light. The cycle track results differed greatly, with a larger percentage of bicyclists willing to run a red light rather than stop. The cycle track differs from a standard bicycle lane in that it is separated from the flow of traffic by a parking lane, limiting the risk of a motor vehicle-bicycle collision. Another key factor of the cycle track along Broadway is that there is no motor vehicle traffic approaching from the right side due to the location of the Portland State University campus. As both the intersections of Broadway and Montgomery and Broadway and Harrison are parallel to the main campus, pedestrian traffic is incredibly high during the mornings and afternoons. Despite this, bicyclists were observed not only running the red lights but swerving to avoid pedestrians who had the right of way and were crossing the intersection. A risk of injury to pedestrians legally crossing the street is not the only risk bicyclists are taking by refusing to obey traffic laws. Many motorists assume bicycles to be held to the same standard that they are held to. When a cyclist is observed by a motorist, they promote the negative perception that drivers have about bicyclists. Furthermore, by failing to obey the laws it makes the cyclists unpredictable, risking a greater chance for a motor vehicle-bicycle collision where there is a chance that the bicyclist would be held at fault for failing to follow the rules of the road. An additional problem comes from the police rarely enforcing bicycle laws (Beck, 2007). While many factors are applied in choosing to cite a bicyclist and there is some degree of selective enforcement being applied, the perception amongst the public is that the laws are not being enforced fairly. The failure to apply laws equally adds to the unpredictable nature of bicyclists among both motorists and pedestrians. While this study is not an in-depth study of bicycle behavior in the entire city of Portland, it outlines a trend in behavior among bicyclists when faced with a red light. Many bicyclists feel that their vehicle is less of a threat than motor vehicles, yet it is shown that major injuries can be caused by a collision with a pedestrian. These injuries are entirely preventable. A stronger focus on bicycle safety in regards to the established laws would likely limit the amount of bicycles that run red lights and risk collisions. It should be noted that bicycles are not the only one at risk of [ 4]
injuring pedestrians, as the motor vehicles who ran red lights were of equal or greater threat to those legally crossing the street. Many of the motor vehicles witnessed did not continue straight through a red light, but made left turns down a two way lane while in a one lane street. This outlines that there is an issue with drivers either being uneducated on this law or that they don t feel that it is a risk. Increased focus should also be placed on the cycle track safety, as the bicyclists riding in it were the highest ratio of offenders. Additional safety would lead to stronger enforcement of laws, allowing for greater predictability and positive perception. With the major risk of injury or death, education and safety studies should begin before a major incident occurs within the city of Portland rather than after. ACKNOWLEDGEMENTS Stephanie Benston; Philip Cohoe; Stacy Harris; Portland State University Public Safety Office; Dr. Chris Monsere, Assistant Professor of Civil and Environmental Engineering, Portland State University; Sgt. Mike Fort, Portland Police Bureau; BikePortland.org; BikeHub REFERENCES Beck, Kirby. "Enforce Bicycle Riding Laws." Law and Order Vol. 55 No. 6, 2007: 82-87. Chong, Shanely, Roslyn Poulos, Jake Oliver, Wendy L. Watson, and Raphael Grzebieta. "Relative injury severity among vulnerable non-motorised road users." Accident Analysis and Prevention Vol. 42, 2010: 290-296. [ 5]
Collette, Christopher. "Pedestrian killed in bicycle accident in Clearwater." WTSP 10 News. July 5, 2010. http://www.wtsp.com/news/local/story.aspx?storyid=135481 (accessed November 2011, 19). Johnson, Marilyn, Stuart Newstead, Judith Charlton, and Jennifer Oxley. "Riding through red lights: The rate, characteristics and risk factors of non-compliant urban commuter cyclists." Accident Analysis and Prevention Vol. 43, 2010: 323-328. Kimmel, Sanford R., and Rollin W. Nagel. "Bicycle safety knowledge and behavior in school age children." Journal of Family Practice Vol. 30 No. 6, 1990: 677. Lee, Henry K. "Woman hit by bicyclist along Embarcadero dies." San Francisco Chronicle. August 12, 2011. http://www.sfgate.com/cgi-bin/article.cgi? f=/c/a/2011/08/11/baj71kma2l.dtl (accessed November 17, 2011). Monsere, Christopher M., Nathan McNeil, and Jennifer Dill. Multi-User Perspectives on Separated, On-Street Bicycle Infrastructure. Portland, November 15, 2011. Oregon Department of Motor Vehicles. Non-Profit License Plates. March 23, 2011. http://www.oregon.gov/odot/dmv/vehicle/platenonprof.shtml (accessed November 2011, 20). Oregon State Legislature. "Chapter 811 - Rules of the Road for Drivers." Oregon Revised Statutes. 2009. http://www.leg.state.or.us/ors/811.html (accessed November 6, 2011).. "Chapter 814 - Pedestrians; Passengers; Livestock; Motorized Wheelchairs; Vehicles With Fewer Than Four Wheels." Oregon Revised Statutes. 2009. http://www.leg.state.or.us/ors/814.html (accessed November 6, 2011). Royal, Dawn, and Darby Miller-Steiger. National Survey of Bicyclist and Pedestrian Attitudes and Behavior. Final Report, Washington: US Department of Transportation, 2008. [ 6]