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39 Now that risk factors have been determined (Step 3) and locations having these risk factors have been identified (Step 4), the next step is to identify appropriate countermeasures or combi- nations of measures that could potentially address risks identified. In Steps 5 and 6, there is also a chance to further refine and prioritize the locations and treatments. Establish a Framework for Selecting Countermeasures To aid agencies in jump-starting their countermeasures selection process, this guidebook provides some general criteria to use when considering options: â¢ Relation to systemic program focus or target crash types or locations. The first phase in the counter measures selection process may begin even as the systemic safety scope is being determined (see Step 1). If the systemic pedestrian analysis is focused only on intersections or only on segments, then the countermeasures considered in this step should be relevant to those locations. â¢ Safety effectiveness. There should be some crash-based evidence that a countermeasure can reduce pedestrian crashes. If crash modification factors (CMFs) or crash-based studies are not available, there should be significant research or well-documented studies showing safety- related benefits (e.g., improved yielding or slowed vehicle speeds) or that the treatment itself has design features related to conflict or exposure reduction (e.g., reduce crossing width or low design speed). â¢ Cost. Cost is a concern for systemic safety measures, and agencies will need to consider abso- lute cost (including installation and maintenance), cost-effectiveness or cost benefit, as well as the funding available. Absolute cost should not necessarily over-ride cost-effectiveness, as more costly design changes may sometimes have greater, more consistent, and potentially longer-lasting benefits than lower-cost markings and signs and may be justified through life expectancy and potential safety benefits for pedestrians and other road users (Gross et al. 2016a). â¢ Feasibility. The feasibility of implementing countermeasures should also be considered. Step 6 discusses considerations such as political concerns, community priorities, the need for public input or stakeholder engagement, equity concerns, and so forth that may affect whether a treatment is feasible to implement at one or more locations. There is also the need to consider feasibility from a technical standpoint: whether the treatment will require addi- tional right of way, how it relates to the Manual on Uniform Traffic Control Devices (2009) recommendations and standards, as well as state or local design guidance or other policies or restrictions affecting potential treatments. C H A P T E R 6 Step 5: Select Potential Countermeasures
40 Systemic Pedestrian Safety Analysis Many states already identify a list of preferred countermeasures or selection criteria based on previous experience or state-sponsored research, so that may be a good starting place. Develop an Initial List of Potential Systemic Countermeasures Table 13 provides a list of a dozen pedestrian countermeasures (further described in the appendix) that were identified through research conducted to develop this guidebook. These counter measures meet some of the basic criteriaârelation to systemic program focus or target crash types or locations; safety effectiveness; cost; and feasibilityâdescribed in the begin- ning of the chapter. These measures may serve as a starting point for agencies as they apply their own criteria to identify countermeasures suitable for systemic implementation in their jurisdictions. The treatments in the first column can help address crash types at signalized locations, espe- cially those resulting from conflicts with turning vehicles, inadequate crossing times (which may also result from interactions with turning vehicles), or long delays for pedestrians that may lead to noncompliance. The treatments in the second column can help address crash types involving pedestrians try- ing to cross at high demand crossing locations along segments or at unsignalized intersections. These treatments primarily aim to help create gaps in traffic on higher volume roads (i.e., PHB) or encourage motorists to yield at locations where traffic speeds are lower and the locations do not meet warrants for a traffic signal. The treatments in the third column may help to address additional risk factors relating to crossing distances or numbers of lanes, a lack of pedestrian conspicuity or visibility, and traffic speed. These treatments can be used to enhance pedestrian safety at any type of crossing, whether signalized or unsignalized. The appendix provides summaries and images of these treatments, including purpose, use, and systemic application considerations. The remaining sections in Step 5 also frequently refer- ence these countermeasures and provide more information on how they relate to crash risks, crash types, and expected crash reduction benefits. More information about the criteria for selec- tion is included in Chapter 5 of the technical report. While each countermeasure has a stand- alone description in this guidebook, it is not necessarily the intent that they be implemented as stand-alone treatments. In many cases, there may be a need to package complementary â¢ Leading pedestrian interval â¢ Longer pedestrian phase â¢ Restricted left turn (protected crossing phase) â¢ In-roadway yield-to- pedestrian (R1-6) sign/ gateway â¢ Advance stop/yield bar and R1-5/5a sign â¢ PHB â¢ High visibility crosswalk â¢ Traffic calming (raised device) â¢ Median crossing island â¢ Reduce number of lanes road diet â¢ Curb extension and parking restriction â¢ Location-specific lighting improvement Intersections Only added) (Locations Only Suitable for Unsignalized midblock or intersection) Suitable for Either Signalized or Unsignalized Crossing Locations (including midblock) Suitable for Signalized (or where signal is Table 13. List of pedestrian crash countermeasures for potential systemic application.
Step 5: Select Potential Countermeasures 41 countermeasures to maximize the safety benefits. For example, high visibility crosswalk mark- ings alone may be insufficient to address certain risk factors but could be implemented along with other treatments, such as medians, advance stop bars, PHBs, or others. Additional Considerations Treatments such as general warning signs were not included in the suggested systemic counter measures list. While general warning signs are typically low cost and meet the criteria for systemic application, the safety benefits for warning signs are inconclusive and signs may need to be used more judiciously than in a systemic process (Zegeer et al. 2013). Beyond the 12 treatments listed, there are certainly other treatments known to be effective that could be considered in a systemic approach. Additional resources are listed at the end of the chapter for agencies that wish to consider a broader set of potential treatments. Many effective treatments, whether systemic or not, could also be used systematically, that is, implemented system wide as part of a standardized policy or design practice. For example, pedestrian count- down signals are now standard practice for all new signalized intersections with pedestrian signals, per the Manual on Uniform Traffic Control Devices (2009). Select Countermeasures The next step in the process involves identifying which treatment options are most applicable to address the characteristics or risk factors identified in previous steps. Countermeasure iden- tification in a systemic process remains similar in some respects to selecting countermeasures for high-crash sites, but this is done for sites across a network with similar risk features and relies in part on understanding patterns across the system from the data analysis. Typically in high crash implementations, diagnosis is done primarily after sites are identified. For effective systemic application: â¢ Countermeasures should target the risks identified. â¢ Treatments should be otherwise appropriate for the site conditions or context. In order not to partially treat a site or sites known to have multiple risks, the package of treatments selected may also need to target multiple types of risks. To get started on the process of matching treatments to risks and location types, consider the example in Table 14, which illustrates one way to consider the risk factors at an identified set of Risk Factor Number of Sites Potential Countermeasures 1. Presence of midblock crosswalk (1 or more) 196 High visibility crosswalk and potentially many others 2. Plus, 4 or 5+ through lanes 26 Advance stop/yield bars and signs, median islands with refuge, and a treatment to increase yieldingâ potentially PHBs or in-roadway yield signs; and potentially others, as revealed by further diagnosis 3. Plus, on-street parking 12 Includes above list, as well as curb extension/parking restrictions Table 14. Potential countermeasures for segments with midblock crosswalks and other risk factors.
42 Systemic Pedestrian Safety Analysis locations and potential countermeasure options. Building on the example from Step 4 on mid- block crosswalks (see Table 10), there are sites with a partial set of characteristics shown. In the first table row, the presence of a midblock crosswalk does not provide much information to aid in countermeasure selection, except that there is likely to be high pedestrian demand for crossing at the location. Considering other risk factors (such as whether the roadway has a factor of 4 or more through lanes, shown in Row 2, and on-street parking, shown in Row 3) significantly narrows the list of sites and also offers additional information to help refine the list of potential countermeasures. The data compiled in Step 2 can be used in this step to consider the risk fac- tors present and refine the list of countermeasures appropriate for the full spectrum of risks and site conditions identified. To further aid in this process, Table 15 provides an evidence-based summary of the relation- ship of the countermeasure to risk factors, crash types, and the relevant location types for the 12 countermeasures highlighted in this guidebook. The Pedestrian Safety Guide and Counter- measure Selection System or PEDSAFE (http://www.pedbikesafe.org/PEDSAFE/) is another tool that agencies can use to help match potential countermeasures to crash types and other safety issues and to narrow the selection of appropriate countermeasures for traffic and road- way context. Noteworthy Practice Some agencies such as North Carolina DOT (Schroeder et al. 2015) and Boulder, Colorado (City of Boulder Transportation Division 2011), have produced their own decision guides for countermeasure selection on the basis of research, the Manual on Uniform Traffic Control Devices (2009), and other jurisdictional factors for making these decisions. See Chapter 1 of the technical report for more information on the North Carolina example. Table 16 provides information based on research and expert guidance on suitable contexts for the 12 countermeasures, though this guidance is not meant to replace local engineering judgment. Ultimately, engineers need to investigate the sites to ensure the appropriateness of the treatments. Table 17 provides information on the pedestrian safety effects of the 12 countermeasures (described in terms of CMFs), as well as any other safety benefits that could be documented. (the appendix provides a more nuanced discussion.) Keep in mind when considering the safety evidence summarized in this table that some crash effects are based on studies from a single jurisdiction, and benefits can vary in practice and when applied systemically. See the Crash Modification Factor Clearinghouse website (Additional Resources section in this chapter) for star quality ratings and other information that help to put the CMFs into context.
Countermeasure Related Risk Factor Related Crash Type Location Type High visibility crosswalk Conspicuity (driver failure to notice); compliance with crosswalks (motorist and pedestrian) Any occurring at crossing locations Signalized or Unsignalized* Traffic calming (raised crosswalk/ speed table) Traffic speed; conspicuity/pedestrian visibility (possibly); non-compliance with crosswalks Through vehicle, pedestrian crossing at signalized/unsignalized location; turning vehicle, pedestrian crossing; pedestrian dart-outs and dashes; unique midblock crossing/pedestrian in roadway types; speeding related Signalized or Unsignalized* Median crossing island Number of traffic lanes; number of lanes crossed in one maneuver; traffic speed (possibly, if roadway narrowed); turning speed at intersections (possibly, if restricts turning radius/corner cutting) Through vehicle, pedestrian crossing at signalized/unsignalized location; turning vehicle, pedestrian crossing roadway; pedestrian dart-outs and dashes; possibly nighttime crashes if replaces two-way, center-turn lane Signalized or Unsignalized* Road diet Number of lanes; number of conflict points associated with driveways/ junctions; traffic speed Through vehicle, pedestrian crossing at unsignalized location; pedestrian dart-outs and dashes; potentially pedestrian walking along the roadway or other pedestrian in roadway types if sidewalks provided; speeding-related/ potentially all types; motorist types, including rear-end and sideswipe/angle Unsignalized* Curb extension with parking restriction Parking presence; conspicuity/visibility; width of crossing Through vehicle, pedestrian crossing at unsignalized location; pedestrian dart-outs and dashes; multiple threats; turning vehicle at intersection; waiting to cross Unsignalized* Improve lighting Conspicuity (driver failure to notice); darkness Nighttime pedestrian crashes Signalized or Unsignalized* In-roadway yield to pedestrian sign (R1- 6) Conspicuity; traffic speed; traffic volume/gap availability Pedestrian crossing, through vehicle at unsignalized location; multiple threats; motorist failure to yield Unsignalized* Advance stop/yield marking and R1- 5/R1-5a sign Number of traffic lanes (> 1 by direction); conspicuity/sight lines Pedestrian crossing, through vehicle at unsignalized location; multiple threats; motorist failure to yield Unsignalized* PHB Traffic volume; no traffic signal/stop sign; multiple traffic lanes (possibly) Through vehicle at unsignalized location; motorist failure to yield; multiple threats; bus related Unsignalized* LPI Conflicts at signalized locations; motorist failure to yield when turning Pedestrian crossing, vehicle turning left or right Signalized Longer pedestrian phase Conflicts at signalized locations; insufficient crossing time Pedestrian crossing, through vehicle; pedestrian crossing, vehicle turning left or right; pedestrian failure to yield types and pedestrian dashes Signalized Protected crossing phase Conflicts with turning traffic; pedestrian delay (due to turning traffic) Pedestrian crossing, vehicle turning left; motorist failure to yield when turning Signalized *Unsignalized locations include midblock crossings lacking signal controls. Table 15. Countermeasures in relation to risk factors, crash types, and location types.
Countermeasure Speed (Limits or General Operating Speed) Volume Number of Lanes High visibility crosswalk Any; consider need for additional treatments at higher speeds. Any; consider need for additional treatments at higher volumes. Any; consider need for additional treatments on multi-lane roads. Traffic calming device Raised crosswalk/speed table Low Generally â¤30 mph Low to moderate (< ~10,000 to 25,000 ADT) Any Median crossing island Any Any Two or more through lanes; minimum space needed is 4 feet but ideally 8 feet Road diet Any Up to 20,000â25,000 ADT (consider potential trade-offs at volumes around 20,000 AADT and up) Three to four lanes; 5+ lanes before treatment (most research based on conversion of undivided four lane to two regular traffic lanes plus TWLTL and bike lanes or parking) Curb extension with parking restriction Potentially any speed on road where parking is present. Any Any; consider bicycle facility type; consider large vehicles/transit effective turn radius. Improve lighting Any Any Any In-roadway yield to pedestrian sign (R1-6) Lower speed (â¤30 mph) (Van Houten and Hochmuth 2017). But yield treatments may be insufficient at higher speed sites. Low-to-moderate pedestrian volume Low-to-moderate ADT (<12,000) (Van Houten and Hochmuth 2017) Two-to-four lanes (most recommended for two-lane roads); median islands provide protection for signs (Van Houten and Hochmuth 2017). Advance stop/yield marking and R1-5/R1-5a sign Any locations reliant on yield with multiple lanes could be considered, but yield treatments not recommended for higher speed roads. Low-to-high ADT (consider need for additional treatments on higher volumes) Two or more lanes per approach direction, especially at uncontrolled crossings PHB Moderate to moderately high speeds. Low-to-medium high ADT (<10,000 to 25,000) depending on other treatments Two or more lanes per direction LPI Low to moderate (â¤45 mph) Moderate to high (10,000 to >25,000) One or more lanes Longer pedestrian phase Any Higher pedestrian volumes; low-to-high motor vehicle volumes (<10,000 to >25,000) Multiple lanes at intersection, including turn lanes Protected crossing phase Any Higher pedestrian volumes; high volumes of left-turning traffic Multiple lanes with dedicated turn lanes Table 16. General traffic considerations and context for countermeasures.
Countermeasure CMFs and Other Estimated Pedestrian Safety Benefits Motor Vehicle CMFs and Crash Types Effects High visibility crosswalk 0.52 urban locations (Chen et al. 2013); 0.63 for high visibility yellow/green markings in urban school zones (Feldman et al. 2010), both replacing standard parallel markings 0.81 for angle, head on, left turn, rear end, rear to rear, right turn, and sideswipe (CMF Clearinghouse citing Chen et al. 2012) Traffic calming device Raised crosswalk/speed table 0.55 (CMF Clearinghouse citing Elvik and Vaa 2004 for areawide traffic calming) 0.70 serious, minor, and possible injuries (CMF Clearinghouse citing Elvik and Vaa 2004) Median crossing island 0.68 (Zegeer et al. 2017a, b) Install raised median, 0.54 to 0.69 range (multiple CMFs available; CMF Clearinghouse citing Alluri et al. 2012a, b; Zegeer et al. 2002) 0.71 â 0.74 (Zegeer et al. 2017a) Road diet Reducing trend in New York City study of 460 sites; no pedestrian crash CMFs yet available. Injury crash reductions expected due to lower travel speeds, fewer lanes, and other potential enhancements (Thomas et al. 2016). 0.71 average urban/suburban roads 0.53 (suburban area) 0.81 (urban area)âall types, all severities (Harkey et al. 2008) Curb extension with parking restriction 0.7 for parking removal to off-street (Toolbox citing Gan et al. 2005); no CMFs yet available for curb extension. Curb extensions reduce pedestrian exposure to crossing distance and improve visibility between pedestrians and motorists. May reduce turning speeds. Unknown/no CMFs yet available for limited parking restrictions or curb extensions. Improve lighting 0.58 nighttime, pedestrian (CMF Clearinghouse, CMF ID 436, citing Elvik and Vaa 2004, for adding lighting, non-specified location types) 0.77 total injury crashes (Harkey et al. 2008; many CMFs available for various crash types on CMF Clearinghouse.) In-roadway yield to pedestrian sign (R1-6) No CMFs yet available. Motorist yielding has been highest with gateway configuration. Speed reductions in some applications (Van Houten 2017, Van Houten and Hochmuth 2017). Unknown/no CMFs yet available Advance stop/yield marking and R1-5/R1-5a signs 0.75 pedestrian crossing crashes 0.64 to 0.86 range (Zegeer et al. 2017a, b) 0.89 total crashes 0.80 rear-end and sideswipe crashes (Zegeer et al. 2017a, b) PHB 0.31 (Fitzpatrick and Park 2010a, b) 0.45 (Zegeer et al. 2017a, b) 0.43 PHB plus advance stop/yield (Zegeer et al. 2017a, b) 0.71 total crashes; 0.85 fatal, serious injury (Zegeer et al. 2017a, b) LPI 0.41 to 0.95 range (Institute of Transportation Engineers 2004, Fayish and Gross 2010, Brunson et al. 2017) Unknown/no CMFs available Longer pedestrian phase 0.50 (CMF Clearinghouse citing Chen et al. 2014) 0.98 for all multi-vehicle crashes (Chen et al. 2013) Protected crossing phase 0.61 urban intersections 0.49 Barnes Dance (CMF Clearinghouse citing Chen et al. 2014) 0.01 left-turn crashes for restricted left (Harkey et al. 2008); other CMFs also available Table 17. Summary of CMFs and other safety benefits of systemic countermeasures.
46 Systemic Pedestrian Safety Analysis Additional Resources See the appendix for images and descriptions of the 12 pedestrian crash countermeasures listed in this chapter and their applications in a pedestrian systemic process. Pedestrian safety treatments are continually being developed and evaluated, so other counter- measures with potential for systemic application are likely to be identified by agencies now and in the future. Following are key resources related to pedestrian crash countermeasures, effective- ness, and selection. Resource Link FHWAâs Safety Effects of Marked Versus Unmarked Crosswalks at Uncontrolled Locations: Final Report and Recommended Guidelines https://www.fhwa.dot.gov/publications/ research/safety/04100/ NCHRP Synthesis 498: Application of Pedestrian Crossing Treatments for Streets and Highways http://www.trb.org/Publications/Blurbs/ 175419.aspx Pedestrian and Bicycle Information Centerâs Evaluation of Pedestrian-Related Roadway Measures: A Summary of Available Research http://www.pedbikeinfo.org/cms/downloads/ PedestrianLitReview_April2014.pdf FHWAâs PEDSAFE: Pedestrian Safety Countermeasure Selection System http://www.pedbikesafe.org/PEDSAFE/ NCHRP Report 674: Crossing Solutions at Roundabouts and Channelized Turn Lanes for Pedestrians with Vision Disabilities http://www.trb.org/Publications/Blurbs/ 164715.aspx TCRP 112/NCHRP 562: Improving Pedestrian Safety at Unsignalized Crossings https://nacto.org/wp-content/uploads/2010/ 08/NCHRP-562-Improving-Pedestrian-Safety- at-Unsignalized-Crossings.pdf Institute of Transportation Engineersâ Designing Walkable Urban Thoroughfares: A Context Sensitive Approach https://www.ite.org/css/ FHWAâs Crash Modification Factor Clearinghouse http://www.cmfclearinghouse.org/ NHTSAâs Countermeasures That Work https://www.nhtsa.gov/sites/nhtsa.dot.gov/ files/812202-countermeasuresthatwork8th.pdf FHWAâs Guide for Improving Pedestrian Safety at Uncontrolled Crossing Locations https://www.fhwa.dot.gov/innovation/ everydaycounts/edc_4/guide_to_improve_ uncontrolled_crossings.pdf