Accidents vulnerability analysis

Perhaps the key to detcrnuiiiiig die consequences of an accident is die study of accident mininiization/prcvendon. This topic receives extensive treatment in Section 17.2. The estimation (not calculadon) of consequences is treated in Section 17.3, which is followed by evacuation procedures (Section 17.4). The next section e.xaniiiies failure modes, effects and critical analysis (FMECA). The cluipter concludes with vulnerability analysis (Section 17.6) and event tree analysis (Section 17.7). 

All recruitment and selection activities should begin with a job analysis. Job analysis allows the task requirements of a job to be precisely determined. Furthermore, job analysis allows the safety risks associated with a job to be determined, and also the identification of the knowledge, skills, and abilities required to work, both safely, and at a satisfactory performance level. It is well established that the occupation or job a person is performing substantially influences accident vulnerability (Ford and Wiggins 2012). In other words, it is vital for safety, for the specific hazards and risks associated with a job to be identified, and conducting a job analysis is an approach which can be used to collect this information. Without the essential information which job analysis provides, it is impossible to provide job applicants with a realistic safety preview for the job (see Chap. 3, Sect. 3.7.2.1), and difiicult to know what competencies a new employee needs to bring to the job, and therefore what should be measured in a selection program. 

Over the years, risk and vulnerability analysis (RVA) has been appUed and adapted for various infrastructures. However, these analyses often do not evaluate the effects of undesired events across sectors. The need for a unified approach to such analyses is addressed in the research project DECRIS (Risk and Decision Systems for Critical Infiastructures). The main objective of DECRIS is to develop an all-hazard generic RVA suitable for a cross-sector infrastmcture analysis. Both safety (accidents, technological failures etc.) and security (dehberate actions) aspects are included. A general case study of the city of Oslo, Norway, focusing on imdesired events in the infrastructures electric supply, water supply, transportation, and ICT, has been carried out (Utne et al. 2008). 

Accident data are only one form of risk information which assists in the identification, assessment and control of risks. Other forms of risk information include reliability data epidemiological studies mortality/morbidity data vulnerability analysis results of audits/inspections insurance claims data and - probably the best - personal experience. Sources of risk information are listed in the Further Reading section of this chapter (see especially the Handbook of Risk Management by Carter et ah). 

Regarding accident data analysis and identification of critical scenarios, the currently ongoing EU project Improving the safety and mobility of vulnerable road users through ITS applications [VRU 13], gives an overview on European cyeling accident data. Analysis of a range of databases has been conducted to identify scenarios for cyclists. The CARE database (European Road Accident Database) has been used as the most widely available database for EU accidents and data fiom national databases of Austria, Finland, Spain, Sweden and the UK have been... 

The analysis of accidents and disasters in real systems makes it clear that it is not sufficient to consider error and its effects purely from the perspective of individual human failures. Major accidents are almost always the result of multiple errors or combinations of single errors with preexisting vulnerable conditions (Wagenaar et al., 1990). Another perspective from which to define errors is in terms of when in the system life cycle they occur. In the following discussion of the definitions of human error, the initial focus will be from the engineering and the accident analysis perspective. More detailed consideration of the definitions of error will be deferred to later sections in this chapter where the various error models will be described in detail (see Sections 5 and 6). 

Analysis in this area gives more conservative assessment of safety than the results obtained through the analysis under the first area in this case the probability of emergency events is assumed equal to 1. However under such approach the obtained numerical estimates are more reliable because the analysis excludes estimates of the probabilities of accident occurrence that is always a rather vulnerable point. 

The system s vulnerability to errors in manufacture, maintenance and operation. These cause a substantial proportion of accidents. In order to reduce the likelihood of such accidents, it is necessary to make an analysis of the design to determine those features of it which are vulnerable to error and to try to eliminate these, or to ensure that instructions, checks, training, etc., can be relied upon to safeguard against the predictable errors (Lloyd and Tye, 1982, p. 111). 

Among the natural phenomena capable to determine serious hazards to industrial plants, earthquakes should be taken into account especially because they are capjable to generate multiple sources of releasing of dangerous substances and domino effects within the same plant, determining the complete destruction of the site. The analysis of p>ast accidents induced by earthquakes has shown the high vulnerability of some typical industrial compxjnents and the severity of the consequences. 

The analysis of past accidents may provide lessons learned to avoid the recurrence of accidents and to improve emergency response in future accidents. In order to obtain data about the vulnerability of the equipment items and to get a possible correlation between the lightning severity and the possible damage states, the historical analysis of past accidents was used as a starting point. In fact, the review of records on industrial accidents triggered by lightning events may allow the identification of ... 

The analysis performed allowed us also to obtain useful information about the substances involved in the accidents. Since atmospheric storage tanks are the most vulnerable items, the more frequently involved substances are gasoline, oil and diesel fuel, usually stored in this kind of vessels. A further result obtained concerns the accident scenarios triggered by hghting events, as reported in Fig. 4. 

Figure 18-8 Accident triangle. The incident , LTA barriers , and vulnerable target concept is the basis for Energy Trace and Barrier Analysis (ETBA) described in Chapter 13.

For analysis purposes, the changes under the accident block make little difference. The three main branches on the specific control factors side continue to be the contributory events that allowed the unwanted energy flow (or hazardous environment), the LTA barriers, and the targets in the energy path (or vulnerable to the hazardous environment). 

Timeline for Event Analysis. The determination of a sentinel event must be initiated within the first forty-eight hours after notification of the accident/event has taken place and the initial fact finding has commenced. The causal analysis needs to be completed as soon as possible, to preserve an accurate account of events, discover the multiple factors contributing to the accident, and decrease system vulnerabilities for other patients. Generally, the initial summary report to the professional executive council, the patient safety steering committee, the board of directors, and the quality oversight committee should be completed within thirty days, but not later than forty-five days after notification of the event. 

The Railway Inspectorate has also been criticized for its use of risk assessment. The main criticism was an insufficient emphasis upon risk assessment procedures, for example, in its data collection and analysis and also in its approach to safety cases (HSE, 2000 t). The validity of this criticism is borne out by recent events. The Southall and Ladbroke Grove accidents demonstrate how cautiously we should approach railway statistics because of their vulnerability to major disasters. Related to this should be some caution in basing future predictions on past performance and most particularly in using this as a basis for arguing against effecting improvements. So it is important that these analyses... 

The horizontal clearance of the navigation span can have a significant impact on the risk of vessel collision with the main piers. Analysis of past collision accidents has shown that bridges with a main span less than two to three times the design vessel length or less than two times the channel width are particularly vulnerable to vessel collision. 

The EOPs or accident management grridance necessary to cope with beyond design basis accidents should be identified by a systematic analysis of the beyond design basis accidents and the plant s vulnerabilities to such accidents, and by the development of strategies to deal with these vulnerabilities. 

Although plant specific PSAs will continue to identify vulnerabilities for particular plants, a large number of additional analysis issues with widespread applicability is not expected. Attention will need to continue, however, with respect to the adequacy of computer modeling of accident phenomena and the applicability of reliability data used in the PSA analyses. 

SHI 12] Shinar D., Safety and mobility of vulnerable road users pedestrians, bicyclists, axtAmoioxcych , Accident Analysis and Prevention, vol. 44, no. 1, pp. 1-2,2012. 

Traffic Safety, Volume 4 of the Research for Innovative Transports Set, presents a collection of updated papers from the TRA 2014 Conference, highlighting the diversity of research in this field. Theoretical chapters and practical case studies address topics such as road safety management and policies, accident analysis and modeling, vulnerable road users safety, road infrastructure safety, ITS and railway safety. 

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