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Introduction: We aimed to identify the possible chain of events leading to fatal scuba diving incidents in Australia from 2001–2013 to inform appropriate countermeasures. Methods: The National Coronial Information System was searched to identify scuba diving-related deaths from 2001–2013, inclusive. Coronial findings, witness and police reports, medical histories and autopsies, toxicology and equipment reports were scrutinised. These were analysed for predisposing factors, triggers, disabling agents, disabling injuries and causes of death using a validated template. Results: There were 126 known scuba diving fatalities and 189 predisposing factors were identified, the major being health conditions (59; 47%), organisational/training/experience/skills issues (46; 37%), planning shortcomings (29; 23%) and equipment inadequacies (24; 19%). The 138 suspected triggers included environmental (68; 54%), exertion (23; 18%) and gas supply problems (15; 12%) among others. The 121 identified disabling agents included medical-related (48; 38%), ascent-related (21; 17%), poor buoyancy control (18; 14%), gas supply (17; 13%), environmental (13; 10%) and equipment (4; 3%). The main disabling injuries were asphyxia (37%), cardiac (25%) and cerebral arterial gas embolism/pulmonary barotrauma (15%). Conclusions: Chronic medical conditions, predominantly cardiac-related, are a major contributor to diving incidents. Divers with such conditions and/or older divers should undergo thorough fitness-to-dive assessments. Appropriate local knowledge, planning and monitoring are important to minimise the potential for incidents triggered by adverse environmental conditions, most of which involve inexperienced divers. Chain of events analysis should increase understanding of diving incidents and has the potential to reduce morbidity and mortality in divers.

In chain of events model, an accident path is defined by a series of sequential events from initiating event to accident realization. In this study, we define accident path as a 5-tuple set comprising hazardous element (HE), initiating event (IE), pivotal event (PV), accident scenario (AS), and consequence (C). We propose a new methodology to identify the path components (i.e., HE, IE, PV, AS and C) and quantify the path using data analytics approach. We have used both proactive (workplace observation (WO) and high risk control program (HRCP)) and reactive data (incident records (IR)) for this quantification. The HEs and their corresponding IEs are extracted from WO and HRCP, and then, IR is used to identify PVs, ASs and Cs. In the process, we have used K-modes categorical clustering and Expectation-Maximization (EM) algorithm based text clustering. We could identify 39 accident paths using proposed approach and after quantification, nine paths are found to be frequently recurring. Preventive strategies are identified for accident paths of high concern. The quantification of accident paths will assist safety management in decision making by prioritizing accident paths and assessing performance of preventive barriers. By the use of data mining techniques, experts will not have to read the huge safety data for accident path analysis. This analysis can be done by experts by identifying safety keywords from the clusters generated by clustering algorithms. This will reduce the labour of safety experts in accident analysis with respect to time and resource.

Objective: The objective of this article is to describe the characteristics of fatal crashes with bicyclists on Swedish roads in rural and urban areas and to investigate the potential of bicycle helmets and different vehicle and road infrastructure interventions to prevent them. The study has a comprehensive approach to provide road authorities and vehicle manufacturers with recommendations for future priorities. Methods: The Swedish Transport Administration’s (STA) in-depth database of fatal crashes was used for case-by-case analysis of fatal cycling accidents (2006–2016) on rural (n = 82) and urban (n = 102) roads. The database consists of information from the police, medical journals, autopsy reports, accident analyses performed by STA, and witness statements. The potential of helmet use and various vehicle and road infrastructure safety interventions was determined retrospectively for each case by analyzing the chain of events leading to the fatality. The potential of vehicle safety countermeasures was analyzed based on prognoses on their implementation rates in the Swedish vehicle fleet. Results: The most common accident scenario on rural roads was that the bicyclist was struck while cycling along the side of the road. On urban roads, the majority of accidents occurred in intersections. Most accidents involved a passenger car, but heavy trucks were also common, especially in urban areas. Most accidents occurred in daylight conditions (73%). Almost half (46%) of nonhelmeted bicyclists would have survived with a helmet. It was assessed that nearly 60% of the fatal accidents could be addressed by advanced vehicle safety technologies, especially autonomous emergency braking with the ability to detect bicyclists. With regard to interventions in the road infrastructure, separated paths for bicyclists and bicycle crossings with speed calming measures were found to have the greatest safety potential. Results indicated that 91% of fatally injured bicyclists could potentially be saved with known techniques. However, it will take a long time for such technologies to be widespread. Conclusions: The majority of fatally injured bicyclists studied could potentially be saved with known techniques. A speedy implementation of important vehicle safety systems is recommended. A fast introduction of effective interventions in the road infrastructure is also necessary, preferably with a plan for prioritization.

Introduction: This study reviews diving deaths that occurred in Tasmanian waters over a 20-year period. Methods: Detailed analysis was undertaken of deaths that occurred from 01 January 1995 to 31 December 2014. The cases were collated from numerous sources. Utilising a chain of events analysis, factors were identified and assigned to predisposing factors, triggers, disabling agents, disabling injuries and cause of death. These were then scrutinised to ascertain regional variables, remediable factors and linkages which may benefit from targeted risk mitigation strategies. Results: Seventeen deaths were identified across this 20-year period, which included one additional case not previously recorded. All were recreational divers and 15 were male. Five were hookah divers, 12 were scuba divers. Important predisposing factors identified included equipment (condition and maintenance), pre-existing health conditions, diver experience and training. These factors can now be used to promote public health messages for divers. Conclusions: This 20-year study highlighted regional variations for Tasmanian deaths and presents opportunities for strategies to prevent diving deaths in the future. Of particular concern was the diving practice of 'hookah' diving, which has no governing regulations. The study highlighted the importance of applying a structured methodology such as chain of events analysis to scrutinise diving deaths.

Introduction Problems concerning occupational safety and health are commonly found in the construction industry, including falling materials, tools or people from a height, stepping on objects, and injuries caused by hand tools. An important factor in occupational safety in the construction industry is the use of scaffolds. All scaffolds used in construction, renovation, repair (including isolating, painting and decorating) and demolition, should be erected, maintained and dismantledin accordance with safety procedures. Therefore, it is crucial to deal with the safety of scaffolds and risk assessment in the construction industry; thus, the way of undertaking the assessment and the liability of assessment seems to be essential for professionals. However, it has been found that those professionals are prone to rely heavily on their own experience and knowledge in decision-making regarding risk assessment. Material and methods The Scaffold Use Risk Assessment Model (SURAM) has been developed for assessing risk levels at various stages of the construction process in various work trades. The SURAM is the result of a research project carried out at 60 construction sites in Poland and Portugal where 504 observations have been completed including both harmful physical and chemical factors, stress level, workers' habits, as well as a hundreds ex-post reconstruction of construction accidents scenarios. Results It was found that the workers' Health Behaviour Index (HBI) seems to be a more direct predictor for development of the unsafe chain of events leading to an accident than the workload, and concentration of harmful factors at the workplace. Conclusions The developed HBI module of SURAM seems to be beneficial for predicting high-risk construction activities, and thus preventing the occurrence of accidents, based on a set of historical accident data.

BACKGROUND An adverse event is defined as any unintentional harm that results in temporary or permanent disability and/or prolongation of hospitalization time, or death of a patient; as a consequence of health care provided by any staff member of the health institution. OBJECTIVES The aim was to describe the adverse events that affect patient safety, reported in 2015 in a private hospital in the city of Cordoba, Argentina. METHODS We analyzed 678 events reported through the computer system on the hospital's intranet. RESULTS The highest frequency of events reported corresponded to the nursing professionals (40.7% ). Problems related to drug therapy process showed the highest frequency of reports (17.7% ), followed by communication failures (11.1% ) and patient's fall (10.3% ). In the notification of the causes of the incident, 51.9% of "No answer" was observed. CONCLUSION In the case of this hospital, this valuable tool is being underutilized. The reports should allow identifying the entire chain of events that lead to the incidents to address effective interventions in patient safety that involve all hospital staff, with greater emphasis on senior staff.

The operating environment of merchant ships is dynamic and complex. Particularly, their engine rooms and bridges have complex structures that contain various equipment. In addition, there is the human factor that manages all this complex structure. The systems on-board ships involve interactions between crew, hardware, and software (man-machine interfaces). As a consequence of the growing complexity of socio-technical systems, traditional accident analysis methods are getting inadequate to analyse the complex systems. The conventional analyses are focused on the chain of events and they have limited ability to overcome non-linear interactions among dynamic and complex system components in maritime transportation. The aim of this paper is to apply a Systems Theoretic Accident Model and Process (STAMP) model for the analysis of a ship allision accident occurring in narrow waters. This is to create a wider view of the accidents rather than a simple chain of events. With the help of detailed STAMP analysis, the dynamic nature of the system, errors in the entire structure, including the human, machine, and software interactions can be analysed. The model also identifies violations of safety constraints at all levels of the control structure, even though the accident involved a complex and dynamic process. The results demonstrate that complex system accidents are not a simple cause-effect chain of events, on the contrary, they are system-based, dynamic, and complex situations. Consequently, the paper tried to reveal all the causes of the Vitaspirit Allison, rather than just one component.

On March 8, 2014, a Malaysia Airlines Boeing 777 carrying flight MH-370 from Kuala Lumpur to Beijing disappeared during its flight. In this paper, we employ a model-based approach to capture and study the chain of events leading to the disappearance of the aircraft. We show that the critical reason for the aircraft’s disappearance was a cyber-physical gap (CPG). The CPG is the difference between the real state of a physical entity and its state as perceived by cybernetic agents. Failure to acknowledge the CPG’s existence, capture it in system models, and incorporate suitable mitigation mechanisms into systems exposed to CPG, has resulted in the past and may result in the future in severe consequences. In the MH-370 case, the plane’s position and adherence to its flight course were misperceived by the air traffic control, resulting in failure to track and find the plane, to this day. Our approach to CPG analysis has been previously shown to assist both designers and users handle emergent situations resulting from CPGs, such as the Three-Mile Island nuclear reactor’s partial meltdown accident in 1979. We propose several mitigation mechanisms, whose integration with air traffic control systems could help prevent similar cases in the future.

Introduction A scuba diving fatality usually involves a series of related events culminating in death. Several studies have utilised a chain of events-type analysis (CEA) to isolate and better understand the accident sequence in order to facilitate the creation of relevant countermeasures. The aim of this research was to further develop and better define a process for performing a CEA to reduce potential subjectivity and increase consistency between analysts. Methodology To develop more comprehensive and better-defined criteria, existing criteria were modified and a template was created and tested using a CEA. Modifications comprised addition of a category for pre-disposing factors, expansion of criteria for the triggers and disabling agents present during the incident, and more specific inclusion criteria to better encompass a dataset of 56 fatalities. Four investigators (raters) used both the previous criteria and this template, in randomly assigned order, to examine a sample of 13 scuba diver deaths. Individual results were scored against the group consensus for the CEA. Raters' agreement consistency was compared using the Index of Concordance and intra-class correlation coefficients (ICC). Results The template is presented. The index of concordance between the raters increased from 62% (194⁄312) using the previous criteria to 82% (257⁄312) with use of this template indicating a substantially higher inter-rater agreement when allocating criteria. The agreement in scoring with and without template use was also quantified by ICC which were generally graded as low, illustrating a substantial change in consistency of scoring before and after template use. Conclusion The template for a CEA for a scuba diving fatality improves consistency of interpretation between users and may improve comparability of diving fatality reports.

A network of serial, parallel and cross-related factors transfers the hazard energy until the accident occurs. This paper aims to discuss the failure of barriers initially built to prevent the accident, the factors that need to be included in the analysis to review human elements and their safeguards, and the need for critical judgment for resilient and accident-alert safe behavior. It is intended to study past accidents and establish relationships between these factors, antecedents and consequences. The availability of a competent team to interpret the chain of events that can lead to the accident is crucial in ending the hazardous energy migration. It is expected to measure the ability to increase or decrease the hazardous energy considering ship collision with oil leak. Analysis of human elements in the project before and after the accident layer factors may suggest changes in safeguards or recommendation of new barriers to the accident.

Background Diagnostic error occurs more frequently in the emergency department than in regular in-patient hospital care. We sought to characterise the nature of reported diagnostic error in hospital emergency departments in England and Wales from 2013 to 2015 and to identify the priority areas for intervention to reduce their occurrence. Methods A cross-sectional mixed-methods design using an exploratory descriptive analysis and thematic analysis of patient safety incident reports. Primary data were extracted from a national database of patient safety incidents. Reports were filtered for emergency department settings, diagnostic error (as classified by the reporter), from 2013 to 2015. These were analysed for the chain of events, contributory factors and harm outcomes. Results There were 2288 cases of confirmed diagnostic error: 1973 (86%) delayed and 315 (14%) wrong diagnoses. One in seven incidents were reported to have severe harm or death. Fractures were the most common condition (44%), with cervical-spine and neck of femur the most frequent types. Other common conditions included myocardial infarctions (7%) and intracranial bleeds (6%). Incidents involving both delayed and wrong diagnoses were associated with insufficient assessment, misinterpretation of diagnostic investigations and failure to order investigations. Contributory factors were predominantly human factors, including staff mistakes, healthcare professionals’ inadequate skillset or knowledge and not following protocols. Conclusions Systems modifications are needed that provide clinicians with better support in performing patient assessment and investigation interpretation. Interventions to reduce diagnostic error need to be evaluated in the emergency department setting, and could include standardised checklists, structured reporting and technological investigation improvements.

Introduction The aim of this study was to identify characteristics of victims of fatal snorkelling and breath-hold diving accidents in Australia from 2001-2013, inclusive, to determine underlying factors and risks associated with such activities and inform appropriate countermeasures. Methods The National Coronial Information System (NCIS) was searched to identify snorkelling and breath-hold diving-related cases reported to Australian coroners for the years 2001-2013, inclusive. Coronial data in the form of findings, witness and police reports, medical histories and autopsies were collected and collated, and descriptive statistics were used to analyse these data. A chain of events analysis was used to determine the likely sequence of events. Results There were 175 identified snorkelling-related fatalities during the study period. Most victims were middle-aged males (mean age 49 years). Pre-existing health conditions were possible contributors to 41% of the deaths, the main being ischaemic heart disease. The majority of deaths occurred in Queensland in inexperienced snorkellers, often in commercial settings. The victim's plight often went unnoticed as they were alone, or poorly supervised, when the incident occurred. Apnoeic hypoxia appeared to have been associated with at least 12.5% of the deaths. The main disabling injuries were asphyxia (40%) and cardiac incidents (35%). Conclusion Human factors, such as chronic health conditions, poor skills and inexperience and poor planning can play a substantial role throughout the chain of events leading to a snorkelling fatality. It is important to educate the community, doctors and dive industry professionals about potential problems associated with the interaction between certain health-related conditions, especially cardiovascular conditions, and snorkelling. Close supervision is strongly recommended for inexperienced snorkellers due to their likely poor skills, as well as for experienced breath-hold divers due to the potential for apnoeic hypoxia.

Security threats on the industrial automated control systems (IACSs) are becoming a growing concern for all the industrial facilities, and in particular for those where large quantities of hazardous substances are stored or handled (e.g. Seveso sites in Europe). Remote (cyber) or physical malicious manipulations of the automated control system of Seveso sites may have consequences comparable to those of conventional major accidents due to internal causes (e.g. loss of containment of hazardous materials, fires, explosions). While consolidated approaches exist to manage and control the cybersecurity of IT and OT systems of a facility, there is an evident lack of procedures to assess the actual link between malicious manipulations of the safety and control systems and the major accidents that can be triggered. In the present study, a specific methodology (PHAROS) was developed to address the identification of major accident scenarios achievable by malicious manipulation of physical components of the plant through the control and safety instrumented systems. The methodology, which exploits a reverse-HazOp concept, also analyses the role of the existing safety barriers in contrasting the chain of events triggered by the malicious manipulation, and may support the definition of design specifications and/or possible IT protection requirements for such barriers. The methodology was applied to a demonstrative case study to understand the features of the results obtained and their potential towards the improvement of the security of the process facility.

Background: A good quality report should lend itself for detailed analysis of the chain of events that lead to the incident. This knowledge can then be used to consider what interventions, and at what level in the chain, can prevent the incident from occurring again. Aim was to study the occurrence of adverse events on the basis of incident reporting. Methods: Critical analysis of incident reporting of adverse events taking place in admitted patients for one year by using WHO Structured questionnaire on patient safety (RF-1 & RF-2 forms) along with their record review and interview to the concerned staff. Results: 253 incidents of adverse events were reported during the study period of one year. Most common screening criteria being, Patient/family dissatisfaction with care received, documented or expressed during the current (221 incidents i.e. 87.35%), followed by hospital acquired infection/sepsis (29 incidents i.e. 11.46%). 13 incidents (5.13%) were reported for unexpected deaths due to adverse events. 38.9% of reported adverse events studied showed signs of health care team responsible for causing adverse events. 39% of adverse events were found preventable and 61% of adverse event was found non-preventable. Conclusions: Incident reporting of adverse events should be encouraged in all hospitals.

Objectives: We aimed at testing a model of the direct and indirect effects of being a part-time 28 farmer on the probability of being involved in an agricultural machinery-related accident, 29 considering the role played by unsafe beliefs and the frequency of use of machinery. 30 Methods: Two-hundred and fifty-two Italian men, regular users of agricultural machinery 31 (age: Mean = 45.1 years, standard Deviation = 17.5), were administered a paper-and-pencil 32 questionnaire addressing their relation with work, unsafe beliefs, and previous experience of 33 machinery-related accidents. 34 Results: Being a part-time farmer showed a positive association with unsafe beliefs only 35 among occasional machinery users. Unsafe beliefs in turn showed a positive association with 36 accidents. 37 Conclusions: The study gave a novel contribution to the knowledge of the chain of events 38 connecting part-time farmers with machinery-related accidents. Preventive training 39 interventions targeting part-timer farmers using agricultural machinery just occasionally 40 should be developed.

Aim To evaluate the performance of a new early warning score (EWS) system by reviewing all serious adverse events in our hospital over a 6-month time period. Method All incidents of unexpected death (UD), cardiac arrest (CA) and unanticipated intensive care unit admission(UICU) of adult patients on general wards were reviewed to see if the escalation protocol that is part of the EWS system was followed in the 24 h preceding the event, and if not where in the chain of events failure occurred. Results We found 77 UICU and 67 cases of the combined outcome (CO) of CA and UD. At least two full sets of EWS were recorded in 87, 94 and 75% of UICU, CA and UD. Patients were monitored according to the escalation protocol in 13, 31 and 13% of UICU, CA and UD. Nurses escalated care and contacted physicians in 64% and 60% of events of UICU and the corresponding proportions for CO were 58% and 55%. On call physicians provided adequate care in 49% of cases of UICU and 29% of cases of the CO. Senior staff was involved according to protocol in 53% and 36% of cases of UICU and CO, respectively. Conclusion Poor compliance with the escalation protocol was commonly found when serious adverse events occurred but level of care provided by physicians was also a problem in a hospital with implemented early warning system. This information may prove useful in improving performance of EWS systems.

There was an accident to a single engine aircraft. From the eye and ear witness accounts, it was established that the accident occurred because of engine failure. After preliminary examination of the wreckage of the crashed engine, a few suspected components were identified for detailed laboratory investigation. The objective was to establish the primary failure in the engine. While majority of the engine components submitted for laboratory analysis showed secondary damages due to either crash impact forces or post-accident fire, the fracture pattern in one of the compressor disks was different from other components of the engine. Fractographic study revealed that the failure of the disk was by fatigue mechanism. Subsequent investigation showed that the fatigue fracture of the compressor disk was the first in the chain of events that led to the engine failure. This finding was further substantiated through fracture mechanics calculations.

Objective: We investigated the risk factors for falls when egressing from agricultural tractors, analyzing the role played by worked hours, work experience, operators' behavior, and near misses. Background: Many accidents occur within the agricultural sector each year. Among them, falls while dismounting the tractor represent a major source of injuries. Previous studies pointed out frequent hazardous movements and incorrect behaviors adopted by operators to exit the tractor cab. However, less is known about the determinants of such behaviors. In addition, near misses are known to be important predictors of accidents, but they have been under-investigated in the agricultural sector in general and as concerns falls in particular. Method: A questionnaire assessing dismounting behaviors, previous accidents and near misses, and participants' relation with work was administered to a sample of Italian tractor operators (n = 286). Results: A mediated model showed that worked hours increase unsafe behaviors, whereas work experience decreases them. Unsafe behaviors in turn show a positive association with accidents, via the mediation of near misses. Conclusions: We gave a novel contribution to the knowledge of the chain of events leading to fall accidents in the agricultural sector, which is one of the most hazardous industries. Applications: Besides tractor design improvements, preventive training interventions may focus on the redesign of the actual working strategies and the adoption of engaging training methods in the use of machinery to optimize the learning of safety practices and safe behaviors

Billions of ringgits are consistently being invested by the oil and gas companies to ensure pipeline integrity, especially to address problems caused by pipelines. However, the existing solutions in predicting corrosion occurrence often lead to an extremely high cost to be implemented. Worse, the current implementations require manual data entry, which lengthen the time taken for processing in order to obtain a reliable corrosion prediction. If a corroded pipeline failed to be predicted much earlier, the pipes might burst and will cause a significant chain of events that will affect the aqua eco-system. The companies will suffer huge financial losses to mitigate the catastrophic situation. Hence, a better pipeline corrosion determination mechanism needs to be developed to address the issues found in this dissertation. Through early prediction on the corrosion occurence, it will provide the user with the knowledge for a better decision making. This paper will deliberate on a system that predicts corrosion rate using the deWaard- Milliams model. Arduino UNO R3 was used in this project, in predicting the corrosion rate. As a proof of concept and performance, simulations were carried out using synthetic dataset to test the efficiency of the proposed system. Synthetic data was generated through the Gaussian function in Java. The proposed prototype was tested. Three types of testing were conducted which are data quality test, accuracy test and corrosion rate analysis. Data quality test is to ensure the synthetic data generated are closely matched with real data. Accuracy test evaluates the predicted corrosion rate against the real field data obtained from literature studies. Corrosion rate analysis provides an overview and comparison between the effects of the parameters determining the corrosion rate and the predicted corrosion rate. The results exhibit the capability of the mechanism to accurately predict the corrosion rate.

Accidents in the process industries are extensively investigated to determine root causes, for lessons learned, and many times in search of the “guilty”. Accidents are seldom simple and most accidents have human elements that led to or facilitated the accident. Many times the people involved in these accidents, when considered individually on their merit, would be considered “good” people yet “bad things” (accidents) still occur. Human errors can be classified as individual, group, and organizational. Individual human errors have been addressed in a number of studies and papers. Many of these classify human errors and treat them probabilistically or cognitively. Less has been said regarding the individual psychological/sociological response/interaction mechanisms that might contribute to an industrial accident. These elements also contribute to a lack of situational awareness which often plays a large part in human error. Group and organizational interactions/dynamics can also contribute negatively to situational awareness and to the chain of events of an accident. Organization errors, which are typically latent, can also facilitate an accident and are many times people enabled for personal and business vested interests. This paper will discuss the effect of human error at the practical plant level in contributing to accidents in the process industries from individual, group, and organizational perspective. The discussion will include psychological/sociological response/interaction mechanisms that can contribute to situational awareness and human error. It will also discuss how complexity, veracity, and quantity of available information can affect the human decision-making process leading to mistakes. Accidents are seldom simple and most accidents have a number of elements that led to or facilitated the accident. When looking at individual elements probabilistically, multiplying probabilities together, it is hard to see how an accident could have occurred. A common refrain “That’s double jeopardy and we don’t have to consider that” is essentially a qualitative probabilistic analysis. Yet we have cases of triple, quadruple, n-jeopardy occurring to cause accidents. The paper will discuss the superimposition of causes and a similar concept of functional resonance in causing accidents.

A power-failure event occurred at the third nuclear power plant (TNPP) in Taiwan in 2001. A chain of events began at 09:36 p.m. on March 16 due to insulation failure associated with flashovers on the 345-kV transmission line. As a result, the 4.16-kV engineered safety features (ESF) buses at the TNPP experienced a loss of power for 2 h and 8 min. This accident was a class 3 emergency (e.g., a class 4 emergency will lead to an overall evacuation of local residents) based on the declared class of emergency in Taiwan. The purpose of this paper is to describe and analyze the chain of events leading to the loss of electrical power. Conclusions on the causes of the outage are drawn and modifications of the system structure are made to improve safety and reliability in a nuclear power plant.

An abnormal accident with no flow in a pumping system occurred with a large displacement of the pipe system. A slow closure of an isolation valve installed in a large suction pipe was the main action. As soon as the valve was closed the 1.6 m diameter pipe moved and the pipe supports were broken, presenting an expansion joint almost fully opened and the main pipe almost broken. This was a critical event that took place in one of the most important pumping stations of the water supply system in Lisbon. In order to avoid future accidents, a detailed analysis was developed as a priority in order to identify the cause of this event. The paper describes the event and the methodology followed in order to fully validate the diagnostic and the proposed chain of events that caused the pipe movement. The process included a careful, in situ observation of the system, hydraulic and structural analyses and some site tests. Ironically, the explanation of abnormal events can give the opportunity to better understand the operation of water supply systems. Weak points in the design and in the operation can then be detected and future accidents can also be avoided.

In many major cities, bicycle usage is on the increase and cycling safety is becoming a critical issue. Most of the existing studies are based on police data which understate both single-bicycle accidents as well as cyclist victims. In France, an estimation based on a road trauma database reveals that cyclists are 8 times more likely to be injured per hour spent on the road compared to motorists. To give a full picture of cycling accidents, as well as to understand how cyclist behavior interacts with other factors in causing accidents, we sur-veyed all injured cyclists in the period 2009-2011, as identified in a medical database of road trauma victims in a French territorial 'départment' (the Rhône, capital city Lyon). Using classification methods we build a typology of 17 recurring configurations of cycling collisions and single-bicycle accidents: 7 concern utilitarian riding (commuting ...), 3 concern recreational riding and 7 concern cycling as a sporting activity. A Multiple Correspondence Analysis (MCA) is then used to check the consistency of this typology, and to gain additional insight on road user behavior by projection of supplementary variables. External factors contributing to cycling accidents, such as 'bad weather' (13%) or 'riding at night' (14%), roadway configuration such as 'cycling infrastructure' (16%) or 'intersections' (25%), and cyclist behavior such as 'alcohol consumption' (5%) or 'speed' (25%) are discriminatory variables that interact in many accident configurations. This study shows how road user behavior-influences each step in the chain of events leading to an accident. In the discussion of study results, some recommendations are made to public authorities aimed at improving cyclist safety.; Dans de nombreuses villes de taille importante, l'usage du Îlo est en augmentation. le sécurité en Îlo devient donc une priorité. La plupart des études existant sur le sujet sont basées sur les données policières qui sous-estiment les accidents de Îlo survenus seuls, de même que le nombre de victimes d'accidents coroprels chez les usagers de Îlo. En France l'estimatioon de ce nombre de victimes à partir d'un Registre detraumatisés de la route donne des chiifres 8 fois plus éleÎs que les données policières pour donner une image plus complète des accidents à Îlo, et pour mieux comprendre comment les habitudes de conduite des cyclistes interagissent avec d'autres facteurs ds la survenue des accidents, nous avons envoyés un questionnaire à toutes les victimes d'accidents de Îlo enregistrées dans le Registre du Rhône sur la période 2009-2011. Nous avons construit une typologie de 17 configurations d'accidents cyclistes : 7 regroupent les accidents survenus sur un ttrajet utilitaire, 3 concernent les accidents lirs de sorties récréationnelles, et 7 concernent les accidents survenus lors d'une activité sportive. A côté des facteurs extérieurs comme le mauvais temps (13%) ou la conduite nocturne (14%), les configurations des infrastructures cyclistes (16%) ou les intersections (25%), les facteurs comportementaux comme la consommation préalable d'alcool (5%) ou la vitesse (25%) sont des variables qui interviennent ds de nombreuses configurations d'accidents cyclistes.

BACKGROUND Notions about the most common errors in medicine currently rest on conjecture and weak epidemiologic evidence. We sought to determine whether cascade analysis is of value in clarifying the epidemiology and causes of errors and whether physician reports are sensitive to the impact of errors on patients. METHODS Eighteen US family physicians participating in a 6-country international study fi led 75 anonymous error reports. The narratives were examined to identify the chain of events and the predominant proximal errors. We tabulated the consequences to patients, both reported by physicians and inferred by investigators. RESULTS A chain of errors was documented in 77% of incidents. Although 83% of the errors that ultimately occurred were mistakes in treatment or diagnosis, 2 of 3 were set in motion by errors in communication. Fully 80% of the errors that initiated cascades involved informational or personal miscommunication. Examples of informational miscommunication included communication breakdowns among colleagues and with patients (44%), misinformation in the medical record (21%), mishandling of patients’ requests and messages (18%), inaccessible medical records (12%), and inadequate reminder systems (5%). When asked whether the patient was harmed, physicians answered affi rmatively in 43% of cases in which their narratives described harms. Psychological and emotional effects accounted for 17% of physician-reported consequences but 69% of investigator-inferred consequences. CONCLUSIONS Cascade analysis of physicians’ error reports is helpful in understanding the precipitant chain of events, but physicians provide incomplete information about how patients are affected. Miscommunication appears to play an important role in propagating diagnostic and treatment mistakes.

Human error is often cited as a major contributing factor or cause of incidents and accidents. Incident surveys in aviation have attributed 70 per cent of incidents to crew error. Although a large proportion of the accidents can be attributed to human error, Reason proposes a view that many accidents are catalyzed by persons not present at the time of the event. In fact, it is this source of latent conditions that pose a most significant threat to the safety of complex systems. Another dimension to human error in aviation are the active errors that can precipitate the alignment or trigger the latent conditions. The risk associated with aviation is a dynamic element that is affected by both latent conditions and situational factors. This dynamic nature is presented here using the cusp model from catastrophe theory. Using Reason’s latent failure model, the descriptive and predictive nature of the cusp model works as a map to illustrate the nature of aviation accidents in terms of “instability” resulting from the alignment of latent conditions and influence of active errors. The SwissAir 111 tragedy of 2 September 1998 is used as a case study to illustrate this model.

The early long-range-jets were operated by five cockpit crew members: Captain, Copilot, Flight Engineer, Navigator and Radio-Operator. Nowadays even the big jets are flown by only two pilots. This development could only be achieved by introducing new technologies to the airline industry and automating aircraft systems. Due to the scientific progress made in the last decades today's aircraft are most reliable – a fact which is clearly reflected by accident statistics. Technical failures became more and more unlikely and the lack of manpower on the flight deck was more than compensated. However, starting in the late 80s a number of accidents occurred to highly automated aircraft, which alarmed accident investigators worldwide. In most of the cases automation was a factor or at least one link in the accident chain of events. The Federal Aviation Administration (FAA) launched a study on “The Interfaces Between Flight Crews and Modern Flight Deck Systems” and came up with numerous findings. In the following article I like to discuss the topic ‘Man-Machine-Interface in modern Transport Systems’ from an Aviation Safety Perspective.

Human errors are common in clinical practice, but they are under-reported. As a result, very little is known of the types, antecedents and consequences of errors in nursing practice. This limits the potential to learn from errors and to make improvement in the quality and safety of nursing care. The aim of this study was to use an Organizational Accident Model to analyse critical incidents of errors in nursing. Twenty registered nurses were invited to produce a critical incident report of an error (which had led to an adverse event or potentially could have led to an adverse event) they had made in their professional practice and to write down their responses to the error using a structured format. Using Reason's Organizational Accident Model, supplemental information was then collected from five of the participants by means of an individual in-depth interview to explore further issues relating to the incidents they had reported. The detailed analysis of one of the incidents is discussed in this paper, demonstrating the effectiveness of this approach in providing insight into the chain of events which may lead to an adverse event. The case study approach using critical incidents of clinical errors was shown to provide relevant information regarding the interaction of organizational factors, local circumstances and active failures (errors) in producing an adverse or potentially adverse event. It is suggested that more use should be made of this approach to understand how errors are made in practice and to take appropriate preventative measures.

Human error is considered a contributing factor in 70% to 80% of all aviation accidents. Because errors can never be eliminated completely, a further reduction of the already low accident rate in this domain will require investments in better support for error management. In particular, a better understanding of the nature and effectiveness of error detection mechanisms is needed. With this goal in mind, NASA Aviation Safety Reporting System incident reports were analyzed in terms of the formal characteristics of underlying errors, the cognitive stage, and the performance level at which these errors occurred, and with respect to the processes that led to their detection and, thus, prevented these incidents from turning into accidents. The majority of incidents involved lapses (i.e., failures to perform a required action) or mistakes, such as errors in intention formation and strategy choice. These errors were most often detected based on routine checks and the observed outcome of an action, respectively. ...

This paper considers the use of “near miss” incidents as part of a pro-active approach to breaking the chain of events that culminate in accidents. Many accidents are preceded by similar near miss incidents, yet such incidents are poorly reported and analysed. Clarifying principles related to near miss incidents, the Accident Ratio Triangle, the Accident Chain and the Accident Potential Model for analysing accidents are presented. Case studies show how near miss analysis may be used a mechanism for monitoring risk management procedures and altering them in response to the changing events and conditions to individual outdoor education programmes. This paper contends that careful reflection on near misses allows us to leam from our mistakes, and prevent their repetition before any damage is done.

The causes of recent fires in hydrocarbon heaters are discussed in this paper. In particular, failures are chosen for which root causes involve trying to get around existing operational shortcomings by making changes to control, instead of carrying out a proper Root Cause Analysis to identify actual causes of deficiencies. In one case, the heater would extinguish due to the poor characteristics of fuel gas. A restart routine was devised, in which previous purging was avoided. In the other case, turning off one burner would turn off the remaining. Instead of addressing the reason why a burner would turn off, the operator modified gas inlet control so that the remaining burners would remain on. Details are given of the chain of events that led to these failures. It is concluded that heaters should be carefully chosen or designed to meet specific operation requirements. Modifications should be avoided whenever possible and carefully planned, in association with the manufacturer when they are unavoidable. In every case, safety systems should be in accordance with modern safety standards. Fil: Booman, Janine. GIE; Argentina. Universidad Nacional de Rosario; Argentina Fil: González, M.O.. Integrity of Oil & Gas Facilities; Argentina Fil: Otegui, Luis Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina

This article describes the catastrophic failure of a liquid CO2 storage vessel and the chain of events that contributed to this incident. This incident happened in Procter & Gamble GmbH's citrus process in Worms, Germany. Three fatalities, over $20 million in property damage, and three month's lost production resulted. Initially less than one-fifth of the storage vessel was available for examination. The force of the explosion had propelled most of the vessel into the nearby Rhein River. The unavailability of the other parts of the vessel seriously hampered the incident investigation and prevented correct determination of the basic cause of the failure. Later recovery and inspection of additional parts of the tank allowed the investigation team to determine the correct basic cause. The results of the inspections conducted on other liquid CO2 vessels are covered. These inspections resulted in most of these vessels being removed from service. Other actions taken to prevent similar incidents include: Elimination of the use of carbon dioxide in many non-critical applications. Development and adoption of specific Company design requirements for liquid CO2 storage systems into standard Design Practices.

Over-reliance in the information provided by electronic chart display and information systems (ECDIS) is a higher risk in navigation. This paper states the advantages of ECDIS and potential human errors, equipment errors and operation errors that have been found in using ECDIS. The root cause analysis for determining the core errors, the error chain in using ECDIS is discussed and identified, then the comments for correctly using ECDIS is proposed.

Events, incidents, accidents, failures, production losses, life reduction of equipment, casualties, and insurance coverage are all critical topics with respect to safety, reliability, and economics. This paper identifies and summarizes some typical failures, chain of events, and causes as related to electrical systems. The aim of the work is to depict the state of the art and the current challenges of engineering practices for the design, operation, and safety of electrical systems in mining environments. Among other situations, a case of failure analysis related with an important loss claim, regarding the loss of field excitation in a mill drive with a synchronous motor is presented. Methods and processes to effectively and consistently evaluate and avoid incidents are also analyzed.

There is a basic misconception that diesel fuel does not explode and/or ignite upon a collision or impact. This particular chain of events, in fact, does occur. However, it is not always thoroughly investigated or understood. The purpose of this paper, through mechanical analysis and accident reconstruction, is to inform truck manufacturers and operators of this hazard. In addition, it will supply design alternatives that will aid in mitigating and/or preventing injuries altogether.

With today's highly coupled flight schedules, any disturbance to the schedule of a flight could have unforeseen impact on the downstream connecting flights. Thus, it is crucial to be able to minimize the effects of the various potential disturbances. Deicing is one such disturbance. During the winter months, deicing procedures associated with snowstorms can cause unexpected delays in the flight schedules. Due to the nonlinear nature of the total time associated with the deicing process (which we call the 'total system time', and includes time of waiting and deicing), it is difficult to predict accurately when an aircraft will complete the deicing process. It is difficult, therefore, to predict how the deicing process will influence the subsequent chain of events. In this paper, a queuing model for the deicing process was developed to assist dispatchers to have a more accurate prediction of the completion time for deicing. Moreover, the two major deicing pads at Detroit Metropolitan Wayne County Airport (DTW) were modeled. Through Monte Carlo simulation, estimates of the total system time for the two deicing pads were derived, along with the corresponding 95% confidence intervals. The simulation results were compared to the historical data in the dynamic runway occupancy measurement system (DROMS), which contains DTW surface surveillance and other aviation related data since October 2002. A decision support tool (DST) was developed, displaying the time estimates. With this deicing DST, airline dispatchers or air traffic controllers can send the next outbound flight to the deicing pad with the least amount of total system time, and, therefore, reduce potential disturbances associated with deicing.

The methodology and selected models used for assessing the frequency of aircraft crashes to critical surface facilities are examined. The DOE Standard model is the basis for comparing other models, particularly those used to assess risk to DOE facilities. The NRC methodology is relevant for nuclear power plants. A rigorous physical model that describes the Markov chain of events and their related probabilities that lead to aircraft hazards to ground facilities is developed. The chain of events is then quantified to provide a basis for comparison and evaluation of mathematical models. It is evident that all quantitative models for aircraft crash frequency assessments are constrained by the limited statistical database available for supporting such risk assessments. Aircraft crashes to critical facilities are rare events, and this condition limits experimental data and verification efforts.Copyright © 2004 by ASME

This document describes the creation of an automatic text-to-scene conversion system, AVis (Automatic Visualizer), for accident reports. Such reports vary from short text passages to long, complex documents describing the chain of events. The visualization of accidents is an important tool in Accident and Incident Analysis [Johnson 2002] For example, computer animations may be used as a training tool, for police and legal reconstruction purposes, or for aiding designers and engineers in analysing accidents and planning future development. Also, it can be difficult for non-expert readers to trace the increasingly complex arguments that are presented in accident reports. The automatic generation of 3D graphics from a text report can be useful for both expert and non-experts.

Problem: There is concern in the aviation community that pilot schedules can lead to fatigue and increased chance of an aviation accident. Yet despite this concern, there is little empirical analysis showing the relationship between pilot schedules and commercial aviation accidents. This study attempts to demonstrate an empirical relationship between pilot schedules and aviation accidents. Method: Data for human factors-related accidents and pilot work patterns were identified. The distribution of pilot work schedule parameters for the accidents was compared to that for all pilots using a chi-square test to determine if the proportions of accidents and length of duty exposure were the same. If the distributions are the same, then one could infer that pilot human factor accidents are not affected by work schedule parameters. Results: The proportion of accidents associated with pilots having longer duty periods is higher than the proportion of longer duty periods for all pilots. Discussion: There is a discernible pattern of increased probability of an accident as duty time increases for commercial aircraft pilots in the United States. Impact on Industry: The analysis suggests that establishing limits on duty time for commercial pilots would reduce risk. Such a rule is likely to be expensive and could substantially impact the commercial airlines. In return, there is likely to be a reduction in the risk of commercial aviation accidents due to pilot fatigue.

An analysis of the causes of runway incursions is discussed. It is seen that control of airport surface operations is complex. Runway incursions usually occur because of multiple factors that combine to form a critical chain of events, culminating in an incident if uninterrupted. Taken individually, these same factors may seem insignificant. It is included that there is no single outstanding cause, and there is no single solution. >

This paper describes a system to create animated 3D scenes of car accidents from written reports. The text-to-scene conversion process consists of two stages. An information extraction module creates a tabular description of the accident and a visual simulator generates and animates the scene. We outline the overall structure of the text-to-scene conversion and the template structure. We then describe the information extraction system: the detection of the static objects and the vehicles, their initial directions, the chain of events, and the collisions. We show snapshots of the car animation output and we conclude with the results we obtained.

Manufacturing, storage, transportation and practical application of energetic materials, particularly high explosives (HE) are tightly connected with the danger of accidental explosion. The real cause of the explosion can be different, e.g. impact, friction, self-heating, influence of a shock wave, radiation, electrical discharge, etc. However, the first stage or the first link of the chain of events (called lately Bowden’s chain [1]) leading to energy evolution which results in destruction and demolition of the environment is always combustion of HE. Correspondingly, every accidental explosion in some sense might be considered as a consequence of a fire. However, the aim of this paper is to analyze only those accidents where explosion can be considered as a result of more or less prolonged influence of a fire on the relatively big amounts of HE.

Human error has been identified as a contributing factor in 75-80% of all aviation accidents. To date, most efforts to improve flight safety have focused on error prevention. A different approach that has received less attention is to avoid the negative consequences of erroneous actions and assessments by supporting their timely detection. In this study, aviation incidents were analyzed in terms of the type of error involved (errors of omission and commission; slips, lapses, and mistakes), the performance level at which the error occurred (skill-, rule-, or knowledge-based performance), and the relation between error types and error detection processes that prevented these incidents from turning into accidents. The majority of reported errors were lapses, i.e., failures to perform a required action, and mistakes, i.e., errors in the formation of an intention. Relatively few slips, i.e., inappropriate executions of intended actions, were reported. Slips appear to be detected and corrected by the pilot before they result in an unsafe situation that is worth reporting. Lapses and mistakes, on the other hand, are more difficult for the pilot committing the error to detect and, in most cases, required intervention by air traffic control. A large percentage of lapses resulted from inattention, either due to some distraction in the cockpit or due to multiple competing demands. Mistakes, on the other hand, frequently occurred as a consequence of some misunderstanding between pilots and air traffic controllers concerning clearances and intentions. Most lapses were detected incidentally based on routine checks of aircraft settings and performance, whereas errors of commission, which include both mistakes and slips, were detected equally often based on monitoring for the immediate outcome of an action and by routine checks. These findings indicate the need for more effective support of error detection, particularly in the case of lapses and mistakes.

A survey has been carried out into the causes of all 2309 disruptions over the last decade of JET operations. The aim of this survey was to obtain a complete picture of all possible disruption causes, in order to devise better strategies to prevent or mitigate their impact. The analysis allows the effort to avoid or prevent JET disruptions to be more efficient and effective. As expected, a highly complex pattern of chain of events that led to disruptions emerged. It was found that the majority of disruptions had a technical root cause, for example due to control errors, or operator mistakes. These bring a random, non-physics, factor into the occurrence of disruptions and the disruption rate or disruptivity of a scenario may depend more on technical performance than on physics stability issues. The main root cause of JET disruptions was nevertheless due to neo-classical tearing modes that locked, closely followed in second place by disruptions due to human error. The development of more robust operational scenarios has reduced the JET disruption rate over the last decade from about 15% to below 4%. A fraction of all disruptions was caused by very fast, precursorless unpredictable events. The occurrence of these disruptions may set a lower limit of 0.4% to the disruption rate of JET. If one considers on top of that human error and all unforeseen failures of heating or control systems this lower limit may rise to 1.0% or 1.6%, respectively.

The paper reviews the work that is currently being done in the Federal Republic of Germany on the design and safety aspects of a large 1000 MW(e) Gas Cooled Fast Reactor. The design studies comprise the layout of both the primary (helium) and the secondary (water-steam) system, the latter to the extent necessary to determine its feed back on the primary system. Safety studies include the analysis of the transient behaviour of the plant under various accident conditions including the design basis accident. It is shown that the GCFR system can be designed to meet the safety requirements currently in use in the Federal Republic of Germany for the Pressurized Water Reactor. Although up to the present time no realistic chain of events has been detected that would lead to accidents beyond the design basis accident, some work is being carried out in the field of hypothetical accidents. Included have been studies on problems associated with handling of gross core melting.

A method for the assessment of risk involved in shipping toxic compounds past nuclear power plants uses a postulated chain of events, starting with a traffic accident causing instantaneous release of the compound as vapor, and leading to incapacitation of control operators in the nuclear plant, described by deterministic and statistical models as appropriate to the respective event. Statistical treatment of relevant atmospheric conditions is a major improvement over more conservative assumptions commonly made in current analyses of this problem. Consequently, one obtains a substantial reduction in the estimated risk expressed in usual terms of the annual probability of an unacceptable event, in spite of the fact that no credit is taken for protective measures other than potential control room isolation. (auth)

With the growth of public air transport, safety in the air is a matter of concern not just to those who design, manufacture and operate aircraft, but to the public at large. After an accident has occurred and an unfortunate chain of events leading to the accident is exposed, it may be easy to say ‘this accident should not have occurred’ or ‘would not have occurred if…’. Publication of annual totals brings forth informed and uninformed comment on the apparent decrease or increase in the accident rate relative to some criteria such as the number of passenger kilometres flown. The objective of this paper is to present a scientific account of the evidence on the relationship between navigation and air accidents and the implications of this evidence for those who are professionally concerned with air navigation. As will become evident, how-ever, there are factors operating which go much deeper than the technical aspects and appear to have their roots in human behaviour, not just of the individual but of organizations and society as a whole.

In the design of a safe road transport system there is a need to better understand the safety challenges lying ahead. One way of doing that is to evaluate safety technology with retrospective analysis of crashes. However, by using retros- pective data there is the risk of adapting safety innovations to scenarios irrelevant in the future. Also, challenges arise as safety interventions do not act alone but are rather interacting components in a complex road transport system. The objective of this study was therefore to facilitate the prioritizing of road safety measures by developing and applying a new method to consider possible impact of future vehicle safety technology. The key point was to project the chain of events leading to a crash today into the crashes for a given time in the future. Assumptions on implementation on safety technologies were made and these assump- tions were applied on the crashes of today. It was estimated which crashes would be prevented and the residual was analyzed to identify the characteristics of future crashes. The Swedish Transport Administration's in-depth studies of fatal crashes from 2010 involving car passengers (n=156) were used. This study estimated that the number of killed car occupant would be reduced with 53 percent from the year 2010 to 2020. Through this new method, valuable information regarding the characteristic of the future crashes was found. The results of this study showed that it was possible to evaluate future impact of vehicle safety technology if detailed and representative crash data is available.