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

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64 LRT Alignment Risk Assessment Checklis t This checklist is intended to provide a framework for a comprehensive risk assessment of a location along an LRT alignment. The risk assessment report would be prepared as a separate do cument or as an attachment to this form, using the form as a table of contents. Completed Reason for assessment: Note the reason for assessment. Possible reasons include collisions(s), collision precursors (near misses or violations), operator or public complaints, and routine assessment of sites on a rotational basis. Area type: Describe the surrounding area (industrial, school, urban core, suburban, proximity to parks and seniors homes/centers, etc.) Collision history: List past collisions (LRT, vehicle, pedestrian, bicycle) and possible causes. If available, list collision precursors. Exposure: If availab le, record the a.m. peak, p.m. peak, and daily volumes for the location for all traffic types involved: Pedestrian volume Road vehicle volu me LRV frequency Roadway design elements: Describe the roadway (if applicable). Include sketches or photos as necessary. Speed and classification Cross-section type (lanes, channelization, islands, barriers, etc.) Sight distance Warning devices Traffic control and Barrier devices Pedestrian environment design: Describe the pedestrian environment (if applicable). Include sketches or photos as necessary. Surface type, grade cro ss-slope, accessibility Horizontal and vertical clearance Obstacles to movement (e.g., crossing padding) Positive guid ance, handrails Warning devices Barrier devices Conflict definition: Define the nature of the conflict (e.g., grade crossing, parallel alignment at grade), with sketch as necess ary to show possible impact types. Lighting: Investigate the impacts of lighting at different times of day. Describe from the pedestrian, vehicle, and LRV operator perspectives. Driver sight lines: Determine if conflict points and the approaches to conflict points are visible by the LRV operator and other users for the expected speed(s). Obstructions (trees, poles, etc.) Horizontal and vertical alignment Potential problems with glare, haze , fog, foliage, snow storage, etc., for different times of day and seasons of the year. Clearance time: If applicable determine if the clearance ti me provided by vehicle, pedestrian, and train sign als is sufficient to safely clear the intersection. Design Co nsistency: Are any aspects of the site features sufficiently unusual to be surprisin g or contrary to the reasonable expectations of the users? (describe) Operator/public complaints: Comment on any complaints that may have been received in context of the site review are they reasonable and/or explainable ? Propose possible solutions/mitigations to address reason(s) for assessment. Figure 6. LRT alignment risk assessment checklist.

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