Improving Pedestrian and Motorist Safety Along Light Rail Alignments (2009)

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59 This chapter develops a methodology for performing risk analysis for safety measures at LRT alignments. A successful methodology for risk analysis should consider these key factors: • Each LRT site is different from the next in terms of physi- cal conditions, traffic demands, control and safety devices, and the populations of motorists, pedestrians, and others using the site (e.g., ages, trip purposes, attitudes, degree of familiarity, etc.). • The methodology must be simple enough to be carried out by local staff possessing specific knowledge about the site and local LRT operations, but without special equipment or extensive training in safety analysis. It is useful to consider how risk analysis has been addressed in the highway safety field. Increased emphasis has been placed on explicitly addressing safety of alignments both at the design and the operational stages. The current best practice is centered on the concept of the road safety audit, which has become a standard practice in many jurisdictions across the United States and around the world. The safety audit process is discussed in the Introduction to the Concept of Safety Audits, Design Stage, In-use Stage, and Practical Methodology for Safety Audits sections. Standards for assessing system safety are discussed in the Existing Standards section. Cues taken from the success of the safety audit concept were used in the development of an LRT safety checklist. A simple checklist-based guide was created to assist local LRT staff in the critical review of safety conditions for a given set of circum- stances defining a particular location. The checklist is discussed and presented in the LRT Risk Assessment Checklist section. Introduction to the Concept of Safety Audits The concept of safety audits is not a new one. Numerous publications outline the safety audit process. They include the Federal Highway Administration’s “FHWA Road Safety Audit Guidelines” (http://safety.fhwa.dot.gov/rsa/rsaguidelines/html/ table_contents.htm). The road safety audit is an approach designed to enhance safety proactively. The audit is a formal safety performance examination of an existing or future road or intersection by an independent audit team. The goal is to ensure the highest level of safety for all road users by identify- ing potential safety concerns and reducing the probability and potential severity of incidents. Safety audits also offer many other benefits, such as reducing the lifecycle cost of a design (when the cost of collisions is factored into analysis during the design process), minimizing the risk of collisions on adjacent transportation networks, and maximizing the application of safety engineering principles. A safety audit uses a multi-disciplinary approach to identify potential collision risks through a detailed examination of all relevant design and environmental factors. When conducted on an existing road network, the interaction between the trans- portation environment and its users can also be observed. The safety audit should consider all potential users of the trans- portation network (i.e., pedestrians, buses, transport trucks, motorists, bikes, LRVs, etc.). Once potential safety concerns are identified, they can be addressed either by eliminating collision-producing elements from the design, and/or by including suitable safety features to mitigate remaining/ existing problems. Design Stage Safety audits conducted during the design phase have the greatest potential for improving safety with lower expendi- tures than would be required at later stages of the project. A safety audit may be conducted during the preliminary design, the detailed design, or both. In general, the earlier in the proj- ect the safety audit is conducted, the greater the potential to improve safety while minimizing costs. These principles also apply, of course, to LRT designs. C H A P T E R 6 LRT Risk Analysis Methodology

60 This concept seems well-known to transit agency personnel as it was raised by local staff at several of the site visit work- shops held for this project. However, the participants gener- ally believed that more could have been done during design to improve safety on their various systems. It is certainly possible that cost or other constraints had an impact on safety features in the design stages. Preliminary Design Stage Safety audits during the preliminary design phase should be conducted once critical decisions regarding route choice and project design/layout have been determined. The safety audit should use both preliminary design drawings and site visits in the evaluation of a design. If multiple alternatives are still under consideration, or if the project will be implemented in stages, the safety of each alternative, stage, or transition between stages should be evaluated separately. The primary objective of a safety audit is to evaluate the rel- ative safety of the proposed design based on all information available. Typical components to be evaluated include horizontal/vertical alignment, sight distances, typical cross sec- tions, intersection/interchange layouts, potential conflict points, and property accesses. Design consistency and user expectations should also be assessed. Any departures from accepted design standards and their effect on safety should be noted. In addition, adequate safety should be ensured in areas where multiple project elements meeting minimum standards interact. The safety audit should be conducted before land acquisition in case significant changes to the design are required. During the site visit(s), the audit team should exam- ine the surrounding transportation network (roads, sidewalks, paths, etc.), and ensure that the proposed design is consistent from the perspective of all potential users. The ability to accommodate future design improvements should also be considered. Conducting a safety audit during the preliminary design phase can avoid wasting valuable design time during the detailed design phase. Detailed Design Safety audits during the detailed design phase should be conducted when detailed design drawings and sufficiently detailed base maps are available. The base map should include all relevant environmental and topographical features in addi- tion to existing infrastructure. Similar to the safety audit dur- ing the preliminary design phase, all alternative stages and transitions between stages should be evaluated separately. A safety audit conducted during the detailed design phases will benefit from access to information not available at earlier stages of the project, but any significant changes to the design will require greater expenditure to implement. Typical com- ponents to be evaluated at this stage of the project include intersection details, lane markings, signals/signs, lighting, geo- metric layout, roadside clearances, and provisions for vul- nerable road users. Field investigations conducted during the detailed design phase of the project can provide the safety audit team with an enhanced understanding of the project layout and potential interactions with surrounding trans- portation networks, particularly if some preparatory work has already begun. If a previous safety audit has been conducted, any issues identified or overlooked during that audit should be re-examined at this stage of the project. If applicable, the safety audit team should assess the potential impact of construction staging and traffic detour plans on the surrounding networks. In-use Stage A safety audit of an existing roadway/railway seeks to iden- tify where collisions will occur and their potential severity. This is accomplished through an examination of available infor- mation, including as-built drawings, previous safety audits (if applicable), volume data, speed data, signal-timing plans, etc. Unlike safety audits conducted during the design phases, observations collected from site visits can be used to diagnose areas of elevated safety risk. Physical evidence such as skid marks, scuff marks, and damage to surrounding features can be used to identify potential hazards. In addition, the audit team can observe the behavior of various users interacting with the transportation facility and key features such as traffic control devices, and assess the potential impact on safety. A safety audit differs from a safety review in that it is pro- active and not reactive. While safety reviews are often initi- ated in response to a high number of incidents at a specific location, a safety audit seeks to identify potential problems before they occur. Therefore, a safety audit does not rely prima- rily on collision history to determine safety issues. Although collision data may be useful to supplement the findings of the safety audit, it may not reflect current and future conditions, and should not be relied upon too heavily. LRT collisions are relatively infrequent events and there- fore do not necessarily reflect all the safety issues at a site. The collision history may lead staff to early conclusions and rec- ommendations that, while not incorrect, may overlook other safety concerns that exist but have yet to be implicated in an incident. The safety audit team may choose not to review the collision data until they have developed recommendations based on all other available information in order to avoid incorporating bias in the analysis. Inspectors should also be mindful of any potential changes to the function or classification of the transportation facility since its construction. Changes might include increased traf- fic volumes and changes in vehicle mix, adjoining land use, or the intensity of development. Elements of the facility that were reasonable and effective in design may no longer serve their

61 purpose if significant changes have occurred in the surround- ing area. Practical Methodology for Safety Audits Numerous existing standards comprehensively address the methodology of safety audits. The methodology summarized below is based on a review of the following documents: • Federal Highway Administration, Road Safety Audit Guide- lines, • Transportation Association of Canada, Road Safety Audits: Canadian Guidelines, and • National Cooperative Highway Research Program Synthesis of Practice 336: Road Safety Audits. The standard methodology for safety audits generally includes the following steps: • Select the safety audit team, • Provide background information to the safety audit team, • Conduct a pre-audit meeting to review project information, • Assess/analyze background information, • Perform site inspections under various conditions, • Prepare and submit safety audit report, • Conduct safety audit completion meeting, • Prepare formal response (completed by project owner/ design team), and • Incorporate safety audit findings into project (where appropriate). Each of these steps is explained briefly below. Additional information is listed in the sources listed above, and in numer- ous other publications on the safety audit process. Select the Safety Audit Team The safety audit team should be an independent multidis- ciplinary team with the appropriate expertise and training to successfully conduct the safety audit. All team members should be impartial; therefore anyone previously involved in the design process should not be included. Auditors must be unconstrained in their ability to comment on potentially con- tentious safety issues. The size and structure of the safety audit team will vary based on the stage and complexity of the project. Provide Background Information to the Safety Audit Team It is the responsibility of the project team to provide the safety audit team with all of the relevant background informa- tion required to complete a comprehensive analysis. The safety audit team should have a broad view of the project objectives and challenges. Information to be provided depends on the stage of the project, but typically includes site data (i.e., traffic data, design standards used, etc.), plans, and drawings. Conduct a Pre-audit Meeting to Review Project Information The purpose of the pre-audit meeting is to clearly outline the scope of the safety audit and review all available informa- tion. The meeting should both familiarize the project team with the safety audit process and introduce the safety audit team to the project. The project and safety audit teams should agree on the delegation of responsibilities, the timetable, and suitable lines of communication. Arrangements for site visits can also be made at this time. Assess/Analyze Background Information Once the safety audit team has been provided with the back- ground information, the next step is to begin to evaluate and analyze it. The first step is usually a brainstorming session involving all members of the multi-disciplinary team. This is typically followed by a desktop evaluation of all of the material provided by the project team. It is critical that this evaluation focus exclusively on safety concerns, and not digress into eval- uation of matters outside of the scope of the safety audit (i.e., cost of alternative designs). Perform Site Inspections under Various Conditions The purpose of the site inspections is to provide the safety audit team with a clear picture of conditions at the project site. Team members are afforded the opportunity to experience the site and surrounding facilities from the perspective of all potential users (pedestrians, car drivers, heavy vehicle opera- tors, LRV operators, cyclists, etc.), and visualize any potential safety concerns that may not be apparent from the design drawings alone. In many cases viewing the site at night in addi- tion to daytime can provide valuable information not other- wise available. The observers should also consider the potential effects of transient conditions such as rainfall or snow storage as applicable. The stage of the project will ultimately determine what useful information can be gleaned from site inspections (see the Design Stage and In-use Stage sections). Prepare and Submit Safety Audit Report The safety audit report should be completed once the safety team has identified all potential safety concerns. The report should include a brief description of the project, including

purpose, scope and any relevant background information. The main body of the report should clearly and concisely outline the design and operational elements reviewed and all potential safety concerns noted. All safety concerns identified should be specific, and a brief description of the potential risk posed to road users should be included. Safety concerns should be organized in a logical format with appropriate headings and subheadings to facilitate response from the project team. Recommendations for improvements are generally not the responsibility of the safety audit team, although they may sug- gest options; decisions about which remedial measures to take are the responsibility of the project team because the project team has a more comprehensive picture of the competing pri- orities of the project. Conduct Safety Audit Completion Meeting After the submission of the safety audit report, it may be beneficial to hold a completion meeting involving key mem- bers of the project team and the safety audit team. The pur- pose of the completion meeting is to formally present the findings of the report, clarify any uncertainties, and facilitate mutual constructive discussion. The purpose of this meeting should be clearly identified. The safety audit team’s objective is to improve the overall safety of the project, not to assign blame or critique the design. The meeting is also not designed to provide the project team with an opportunity to dispute the findings of the safety audit. All participants should view the meeting as an opportunity to identify the safety concerns clearly and identify potential measures to improve safety. Prepare Formal Response by Project Owner/Design Team After reviewing the safety audit report, it is important for the project team to document a formal response to the find- ings of the safety audit report. The response should identify the actions the project team intends to take for each of the safety concerns identified. In the case when no action will be taken for a particular safety concern, the response should clearly identify the rationale behind the decision. Incorporate Safety Audit Findings into Project Once the formal response has been submitted to the safety audit team, the project team should proceed to incorporate the agreed recommendations into the project. The inclusion of improvements involving a significant increase in project cost or duration may not be feasible. If consensus cannot be reached regarding a particular issue, the safety audit team should document the differences. Existing Standards A number of existing standards for assessing system safety are available. The most widely referenced work in the litera- ture examined was the Department of Defense Standard Prac- tice for System Safety (MIL-STD-882D) (U.S. Department of Defense, 2000). This document is discussed in the following section. In the FTA’s publication Hazard Analysis Guidelines for Transit Projects, the FTA recommends conducting hazard identification, assessment, and resolution in conformance with the latest version of the MIL-STD-882D (10). Information provided by local LRT staff during the site vis- its indicates that a number of LRT agencies are using the MIL- STD-882D standard to conduct risk analysis. For example, NJT noted that it uses the MIL-STD-882D standard to evaluate the design of any new system before it is built and operated. NJT emphasized the need to “design out” hazards at the design stage of a project, emphasizing the role of peer reviews in this process. In addition, whenever changes are proposed to the existing system, NJT conducts an operation hazard analysis to list possible hazards resulting from the change in operation, along with possible mitigating measures. DoD Standard Practice for System Safety (MIL-STD-882D) As mentioned above, the U.S. Department of Defense has published a document entitled Standard Practice for System Safety (MIL-STD-882D). Two agencies that participated in the site visits referenced their use of MIL-STD-882D as a basis for their risk management approach. The document provides standardized requirements for developing and implementing a system safety program. The standard is designed as a general guideline for use in a wide variety of contexts and is not focused primarily on transportation applications. The document provides a standard methodol- ogy for use in the identification of hazards, risk assessment, and mitigation of mishap risk through the implementation of design requirements and management controls. “Mishap risk” is defined as “an expression of the impact and possibil- ity of a mishap in terms of potential mishap severity and probability of occurrence.” The document recommends a systematic procedure con- sisting of the following eight steps, which encompass the entire life cycle of the system: 1. Documenting of system safety approach; 2. Identifying hazards; 3. Assessing mishap risk; 4. Identifying mishap risk mitigation measures; 5. Reducing mishap risk to an acceptable level; 6. Verifying mishap risk reduction; 62

63 7. Reviewing hazards and acceptance of residual mishap risk by the appropriate authority; and 8. Tracking hazards, their closures, and residual mishap risk. The concise standard is a guideline rather than an exhaus- tive treatment of system safety. The document also contains an appendix entitled “Guidance for the Implementation of a System Safety Effort” that offers further elaboration on the definitions and procedures contained in the main text. The identification of potential hazards is highly system specific, so there is not much elaboration provided on the topic. The standard recommends a systematic hazard analy- sis process including evaluation of the system environment and intended application, including historical data and data available from similar systems. The standard emphasizes the need to develop methods that accurately and meaningfully assess both the likely severity and probability of occurrence of potential mishaps. The appendix contains suggestions for describing mishap severity categories and probability levels, while noting that adaptation to the spe- cific system is generally required. Severity categories are clas- sified as catastrophic, critical, marginal, or negligible, based on the following factors: potential for death, disability, injury, or occupational illness; monetary loss; and environmental damage. Mishap probability, defined as the probability of the mishap occurring over the life of the system, can be classified either qualitatively or quantitatively. The recommended cate- gories for mishap probability are frequent, probable, occasional, remote, or improbable. Risk assessment values are determined using a combination of both mishap probability and potential severity. For exam- ple, a hazard classified as frequent and catastrophic would be assigned a risk assessment value of one, a hazard classified as probable and catastrophic would be assigned two, etc. These risk assessment values would be used to group individual haz- ards into mishap risk categories. These risk categories can then be used to prioritize treatments and determine the mishap risk acceptance level. The standard recommends an iterative approach to the identification of mishap risk mitigation measures which termi- nates only when residual mishap risk has been reduced to an acceptable level. The four steps, in order of preference, are: eliminate hazards through design selection, incorporate safety devices, provide warning devices, and develop procedures and training. The standard reiterates the need to follow a compre- hensive, systematic process in identifying risk mitigation mea- sures as opposed to simply providing signage. The emphasis on verifying successful risk reduction and reviewing and tracking hazards shows that maintaining system safety is an ongoing process that does not terminate once the hazard is addressed. LRT Risk Assessment Checklist This section describes a way to perform risk analysis for safety measures along LRT alignments. A checklist was com- pleted using information obtained through research and con- sultation with various transit agencies. Table 33 shows the Title of Publication Organization Author(s) Year Pedestrian-Rail Crossings In California: A Report Compiling the Designs and Devices Currently Utilized at Pedestrian-Rail Crossings within the State of California California Public Utilities Commission Richard Clark 2008 TCRP Report 69: Light Rail Transit: Pedestrian and Vehicular Safety Transit Cooperative Research Program Hans W. Korve Susan Gilbert Brent D. Ogden Ed Boni Joaquin T. Siques Michele Butchko Douglas M. Masnsel Jane C. Stutts Hoy A. Richards Ronald G. Hughes 2001 Investigation into Station Pedestrian Crossings (Including Pedestrian Gates at Highway Level Crossings) U.K. Depart me nt of Transportation – Rail Accident Investigation Branch The Canadian Road Safety Audit Guide Transportation Association of Canada Sany Zein Geoffrey Ho Paul de Leur 2000 2006 Road Safety Audit Guidelines University of New Brunswick Transportation Group Eric Hildebrand Frank W ilson 2008 Table 33. Primary sources used in developing the safety checklist.

64 LRT Al ignment Risk As sessment Checklis t Th is ch ecklist is intend ed to pr ov id e a fr am ew or k fo r a co mp rehensiv e risk as se ss me nt of a location along an LRT a lignm ent. Th e risk ass ess ment report wo ul d be prep ar ed as a separate do cu me nt or as an attach me nt to th is fo rm , us ing the fo rm as a ta bl e of co ntents. Co mp leted Reas on fo r as sess me nt : No te the r eason fo r assess me nt. Poss ib le reas ons inclu de collis io ns(s), colli sion pre cu rs or s (ne ar mi sses or vi ol ation s) , operator or public co mp laint s, and r out ine assess me nt of sites on a ro ta tional ba sis. Area type : De scri be the surrounding area (ind ustr ial, sc ho ol, ur ba n co re, subur ba n, proxim it y to park s and seniors ho me s/centers, etc.) Co llisio n hi story: Li st past collis ions (L RT, vehicle, pe de strian, bi cy cle) an d possible ca us es. If available, list collisio n precurs ors . Ex posure: If availab le , record th e a.m . peak , p. m. peak, and daily volum es fo r th e locatio n fo r all tr affic ty pes inv ol ve d: Pe destri an vo lu me Road vehicle volu me LR V freq ue nc y Road wa y desi gn elem en ts: De sc ribe the ro ad wa y (i f ap plic ab le). Include sketch es or photos as necessa ry. Speed and cl assif ication Cro ss-sectio n ty pe (lan es , channe lization, is lands , barriers, etc.) Sight di stance Wa rnin g devi ce s Tr af fi c co ntrol an d Barrier de vices Pedest rian enviro nm en t de sign : Describe the pe de strian environm ent (if applicable). In clu de sk etches or photos as ne cessar y. Surf ace ty pe, grade cro ss-slope, accessibility Horizontal a nd ve rtical clearance Obstacles to mo veme nt (e.g., crossing padding) Positiv e guid an ce, handrails Wa rnin g devi ce s Barrier devices Conflict defi ni tion : De fi ne the nature of th e conflict (e.g., grade crossing, parallel alignment at grade), with sketch as necess ar y to show po ssi bl e im pact ty pes. Lighting: Investig ate th e im pacts of lig hting at dif ferent tim es of day . De scribe fr om the pede strian , ve hi cl e, an d LR V operator perspectives. Driver si gh t li nes: Dete rm in e if c onf lict po in ts an d th e approaches to conflict po in ts ar e vi sible by the LR V operator a nd ot he r users fo r the ex pe cted speed(s). Obstru ctions (trees, poles, etc.) Horizontal a nd ve rtical alig nm ent Potentia l pr oble ms w ith glare, haze , fo g, fo liage , snow storage, etc., for different times of day and seasons of the ye ar. Clea ra nce ti me : If applicable de te rm ine if th e clearance ti me pr ovided by vehicle, pedestrian , a nd tr ain sign al s is su ffi cient to safe ly clear the intersection. Design Co nsist en cy : Are an y asp ects of the site features su ff iciently unusual to be surprisin g or cont ra ry to the reaso nable expecta tions of the us ers? (describe) Ope ra to r/public co mp la in ts : Comment on an y co mp laints th at ma y ha ve be en received in co nt ex t of th e site review – are they reasonable and/ or explainable ? Pro p ose p os sible so lu ti on s/ mi ti g at io ns to add res s reaso n ( s ) fo r assess me nt. Figure 6. LRT alignment risk assessment checklist.

65 publications referenced in the development of the LRT risk assessment checklist. The publications reviewed and the discussions conducted with the various transit agencies visited suggested that the con- cept of a checklist was the preferred option for use in LRT risk assessments. A rigid framework was not supported as it would not be adaptable to the wide range of situations found in prac- tice. At the Minneapolis workshop, it was suggested that due to the wide variety of information that may need to be col- lected for an LRT audit, the checklist should be organized into general categories for consideration and should avoid taking a more detailed approach. In safety audits, checklists are intended to serve as a guide or memory aid to help identify safety issues and ensure something important is not overlooked. They are useful for supplement- ing knowledge and experience and for providing direction to an investigation. It is important to recognize that checklists should not be considered an exhaustive list of all possible issues to be addressed. The safety audit team must use judgment to establish the relevance of each item on the list to a project. Even if a particular item appears to be irrelevant, it may lead the investigator to consider other factors that may otherwise have been overlooked. Taking into account the above considerations and the feed- back received from the local LRT agency workshops, the proj- ect team developed the “LRT Alignment Risk Assessment Checklist,” as shown in Figure 6. The LRT Alignment Risk Assessment Checklist will pro- vide guidance to LRT staff and other groups conducting a risk assessment. Its application will cover key factors and will help ensure that important considerations are not overlooked in the study of any given site. Individual agencies can expand the checklist as circumstances and the situation require. It is hoped that the checklist’s broad descriptions will not be viewed too narrowly in practice and that important elements of a site users’ perceptions will be included in the risk assessment.