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HFG MARKINGS Version 1.0 MARKINGS FOR PEDESTRIAN AND BICYCLIST SAFETY Introduction Markings for pedestrian and bicyclist safety refers to pavement marking techniques to encourage safe practices for road sharing by vehicles, pedestrians, and bicycles. Pedestrian markings include crosswalks, which are defined as marked or unmarked extensions of sidewalks or shoulders across intersections (1). Crosswalks may also be located midblock, but only if marked. Bicycles and vehicles may utilize shared lanes on either rural or non-rural roadways. The purpose of markings in shared lanes is to notify users that the lane is shared and clearly define the positioning of the traffic flows. Design Guidelines RECOMMENDATIONS FOR INSTALLING MARKED CROSSWALKS AND OTHER PEDESTRIAN IMPROVEMENTS AT UNCONTROLLED LOCATIONS Roadway Type Vehicle ADT Vehicle ADT Vehicle ADT Vehicle ADT (Number of travel 9,000 > 9,000 to 12,000 > 12,000 to 15,000 > 15,000 lanes and median type) 30 35 40 30 35 40 30 35 40 30 35 40 mi/h mi/h mi/h mi/h mi/h mi/h mi/h mi/h mi/h mi/h mi/h mi/h 2 lanes C C P C C P C C N C P N 3 lanes C C P C P P P P N P N N Multilane ( 4 lanes) with C C P C P N P P N N N N raised median Multilane ( 4 lanes) without C P N P P N N N N N N N raised median C: Candidate site for marked crosswalk. Marked crosswalk can be considered after an engineering study and confirmation of 20 pedestrian (or 15 elderly/child) crossings per peak hour. P: Possible increase in pedestrian crash risk may occur if crosswalks are added without other crossing improvements; locations should be monitored and enhanced with other improvements if necessary before adding a crosswalk. N: Marked crosswalks should not be added alone because pedestrian crash risk may increase; treatments such as traffic calming measures, traffic signals with pedestrian signals, or other crossing safety improvements should be considered. Source: adapted from Zeeger et al. (1) PLACEMENT OF RECOMMENDED SHARED-USE LANE SYMBOL FOR BICYCLISTS AND VEHICLES Approximate Parked Recommendations: Passenger Vehicle Place the centerline of the Width from Curb: 7 0 shared-use arrow 11 ft from the curb. Use the bike-and-chevron symbol to denote a Approximate Open Door Width shared-use lane. Centerline of Marking to Door Placement of shared-use arrow from curb. Source: Birk, Khan, Moore, and Lerch (2) Based Primarily on Based Equally on Expert Judgment Based Primarily on Expert Judgment and Empirical Data Empirical Data 20-6
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HFG MARKINGS Version 1.0 Discussion Crosswalks: Zeeger et al. (1) provide guidelines for the locations where marked crosswalks should be installed based upon a study of pedestrian crashes at marked and unmarked crosswalks. The guidelines apply to uncontrolled locations excluding school crossings. Crosswalks should not be installed in locations where additional pedestrian safety risks exist (e.g., poor sight distance, confusing designs) without other design features or traffic control devices (1). Crosswalks alone do not make crossings safer or guarantee that more vehicles will stop for pedestrians. Nowakowski (3) found that there are three critical locations where potential vehicular-pedestrian conflict could occur: the mid- block crossing and the left and right turning lanes at an intersection. The difficulty for the driver is detecting pedestrians because visual scanning and attention are limited. It is recommended that parking be eliminated on the approach to uncontrolled crosswalks to improve vision between pedestrians and drivers. The Uniform Vehicle Code (4) specifies that parking should be prohibited within 20 ft of a crosswalk at an intersection (which could be increased to 30 to 50 ft in advance of a crosswalk on a high-speed road). Design of the shared-use arrow: Shared-use arrows (also referred to as "sharrows") on roadways attempt to reduce safety problems such as "dooring," where bicyclists ride into parked vehicle doors when ajar; wrong-side riding; sidewalk riding; motorists squeezing out bicyclists; and other aggressive behaviors (2). Shared pavement markings can increase the percentage of bicyclists riding in the street, which can help reduce crashes with turning vehicles. Two bicyclist surveys and an on-road study regarding a number of shared-lane markings were conducted in San Francisco (2, 5). The lane markings tested were bike-and-chevron (shown on the previous page), bike-in-arrow (bicyclist inside of an arrow outline), and a separated bike-and-arrow. During the on-road study, the bike-and-chevron marking significantly reduced sidewalk riding (by 35%) and wrong-way riding (by 80%). It also increased all distances between moving cars, cyclists, and parked cars. Overall, 60% of cyclists thought that the markings positively affected their sense of safety and preferred the bike- and-chevron marking by a 2:1 ratio. However, 30% of cyclists indicated that the markings tested meant that bikes have priority, rather than that the lane is shared. The distance of the shared-use arrow from the curb is based upon parked vehicle width. Birk et al. (2) observed that the 85th percentile of car doors open 9 ft 6 in. from the curb, the average bicycle width is 2 ft, and 6 in. of "shy distance" is added between the open door and bicycle handlebars. In total, these distances indicate that the centerline of the pavement marking should be 11 ft from the curb. Design Issues Crosswalk lighting: In-roadway crosswalk warning lights can provide pedestrian safety benefits. With in-roadway warning lights: passing vehicle speeds decreased from 7% to 44% (6, 7), the percentage of drivers yielding to pedestrians increased during day and night by 26% to 162% (8, 9), and the percentage of drivers who saw the crosswalk, saw a pedestrian, and accurately stated the presence of the pedestrian increased by 13%, 25%, and 38%, respectively (8). Shared lanes: Shared-use lanes often exist where there is too little space available to create a dedicated bicycle lane. When space is available, a bicycle lane or wide curb lane may be created; however, there is disagreement as to which is better. See Hunter, Stewart, Stutts, Huany, and Pein (10) for a discussion of each lane type. Cross References None. Key References 1. Zeeger, C.V., Stewart, J.R., Huang, H.M., Lagerwey, P.A., Feaganes, J., and Campbell, B.J. (2005). Safety Effects of Marked Versus Unmarked Crosswalks at Uncontrolled Locations, Final Report and Recommended Guidelines (HRT-04-100). McLean, VA: FHWA. Retrieved from http://www.tfhrc.gov/safety/pubs/04100/04100.pdf. 2. Birk, M., Khan, A., Moore, I., and Lerch, D. (2004). San Francisco's shared lane pavement markings: improving bicycle safety. (Prepared for San Francisco Department of Parking and Traffic). Alta Planning + Design. Retrieved June 3, 2008 from http://www.sccrtc.org/bikes/SF-SharedLaneMarkingReport-Feb04- FINAL.pdf. 3. Nowakowski, C. (2005). Pedestrian warning human factors considerations. Retrieved from http://path.berkeley.edu/~cychan/Research_and_Presentation/Pedestrian_Detection_TO5200/Crosswalk_ HF.pdf. 4. National Committee on Uniform Traffic Laws and Ordinances (1992). Uniform Vehicle Code: 2000. Evanston, IL. 5. Center for Education and Research in Safety (2002). Report on human factors comparison on perceived meaning of three alternative shared use symbols (Submitted to The City of San Francisco). Retrieved from http://members.cox.net/ncutcdbtc/sls/cerssf02.pdf. 6. Dougald, L. (2004). Development of Guidelines for Installation of Marked Crosswalks (VTRC 05-R18). Charlottesville: Virginia Transportation Research Council. 7. Whitlock & Weinberger Transportation (1998). An Evaluation Of A Crosswalk Warning System Utilizing In-Pavement Flashing Lights [Executive Summary]. Retrieved from http://www.spotdevices.com/docs/studies/EvaluationCrosswalkWarningSystemUtilizingInPavementLights.pdf. 8. Katz, Okitsu & Associates. (2000). Illuminated crosswalks: An evaluation study and policy recommendations (Prepared for the City of Fountain Valley, California). Tustin, CA. Retrieved from http://www.xwalk.com/images/advocacy/ftnvlly_study.pdf. 9. California Department of Transportation. (2004). MUTCD 2003 California Supplement, Part 4: Highway Traffic Signals, Section 4L.02 In-Roadway Warning Lights at Crosswalks. Sacramento. Retrieved from http://www.dot.ca.gov/hq/traffops/signtech/mutcdsupp/supplement.htm. 10. Hunter, W.W., Stewart, J.R., Stutts, J.C., Huany, H.H., and Pein, W.E. (1998). A Comparative Analysis of Bicycle Lanes versus Wide Curb Lanes: Final Repor t. (FHWA-RD-99-034). McLean, VA: FHWA. 20-7