Zoekresultaten

Tracing New Safety Thinking Practices in Safety Investigation Reports

Modern safety thinking and models focus more on systemic factors rather than simple cause-effect attributions of unfavourable events on the behaviour of individual system actors. This study concludes previous research during which we had traced practices of new safety thinking practices (NSTPs) in aviation investigation reports by using an analysis framework that includes nine relevant approaches and three safety model types mentioned in the literature. In this paper, we present the application of the framework to 277 aviation reports which were published between 1999 and 2016 and were randomly selected from the online repositories of five aviation authorities. The results suggested that all NSTPs were traceable across the sample, thus followed by investigators, but at different extents. We also observed a very low degree of using systemic accident models. Statistical tests revealed differences amongst the five investigation authorities in half of the analysis framework items and no significant variation of frequencies over time apart from the Safety-II aspect. Although the findings of this study cannot be generalised due to the non-representative sample used, it can be assumed that the so-called new safety thinking has been already attempted since decades and that recent efforts to communicate and foster the corresponding aspects through research and educational means have not yet yielded the expected impact. The framework used in this study can be applied to any industry sector by using larger samples as a means to investigate attitudes of investigators towards safety thinking practices and respective reasons regardless of any labelling of the former as “old” and “new”. Although NSTPs are in the direction of enabling fairer and more in-depth analyses, when considering the inevitable constraints of investigations, it is more important to understand the perceived strengths and weaknesses of each approach from the viewpoint of practitioners rather than demonstrating a judgmental approach in favour or not of any investigation practice.

Correlation of changes in the employment costs and average task load with rates of accidents attributed to human error

Market competition and global financial uncertainty have been the principal drivers that impel aviation companies to proceed to budget cuts, including decreases in salary and work force levels, in order to ensure viability and sustainability. Under the concepts of Maslow and Herzberg’s motivation theories, the current paper unfolds the influence of employment cost fluctuations on an aviation organization’s accidents attributed to human error. This study exploited financial and accident data over a period of 13 years, and explored if rates of accidents attributed to human errors of flight, maintenance and ramp crews, correlate with the average employment expenditures (N=13). In addition, the study took into account the relationship between average task load (ratio of flying hours per employee) and accident rates related to human error since task load, as part of total workload, is a constraint of modern complex systems. The results revealed strong correlations amongst accident rates linked to human error with the average employment costs and task load. The use of more specific data per aviation organizational department and professional group may further validate the results of this study. Organizations that seek to explore the 2 association between human error and employment budget and task load might appropriately adapt the approach proposed.

By accident or design

An introduction of accidents’ classification based on their outcome control

Most safety oriented organizations have established their accidents classification taking into account the magnitude of the combined adverse outcomes on humans, assets and the environment without considering the accidents‟ potential and the actual attempts of the involved persons to intervene with the accident progress. The specific research exploited a large sample of an aviation organization accident records for an11 years‟ time period and employed frequency and chi-square analyses to test a new accident classification scheme based on the distinction among the safety events with or without human intervention on the accident scene, indicating the management or not of their ultimate consequences. Furthermore, the research depicted the effectiveness of personnel strains to alleviate the accident potential outcomes and studied the contribution of time, local and complexity factors on the accident control attempt and the humans‟ positive or negative interference. The specific newly proposed accident classification successfully addressed the “controlled” or “uncontrolled” traits of the safety events studies, prior their severities consideration, and unveiled the effectiveness of personnel efforts to compensate for the adverse accident march. The portion between controlled and uncontrolled accidents in terms of the human intervention along with the effectiveness of the later may comprise a useful safety performance indicator that can be adopted by any industry sector and may be recommended through international and state safety related authorities.

The controllability classification of safety events and its application to aviation investigation reports

This paper proposes an amendment of the classification of safety events based on their controllability and contemplates the potential of an event to escalate into higher severity classes. It considers (1) whether the end-user had the opportunity to intervene into the course of an event, (2) the level of end-user familiarity with the situation, and (3) the positive or negative effects of end-user intervention against expected outcomes. To examine its potential, we applied the refined classification to 296 aviation safety investigation reports. The results suggested that pilots controlled only three-quarters of the occurrences, more than three-thirds of the controlled cases regarded fairly unfamiliar situations, and the flight crews succeeded to mitigate the possible negative consequences of events in about 71% of the cases. Further statistical tests showed that the controllability-related characteristics of events had not significantly changed over time, and they varied across regions, aircraft, operational and event characteristics, as well as when fatigue had contributed to the occurrences. Overall, the findings demonstrated the value of using the controllability classification before considering the actual outcomes of events as means to support the identification of system resilience and successes. The classification can also be embedded in voluntary reporting systems to allow end-users to express the degree of each of the controllability characteristics so that management can monitor them over time and perform internal and external benchmarking. The mandatory reports concerned, the classification could function as a decision-making parameter for prioritising incident investigations.

The concept towards a Standard Safety Model (STASAM v.0)

In safety science and practice, there have been various safety models, each of them reflecting a particular approach to safety management and accident causality. The large variety of models suggested in literature and applied in practice serve the communication of diverse perspectives towards safety and the need to consider contextual factors, but it does not allow the establishment of a common language within and across organisations and industry sectors. Considering the potential benefits of talking a lingua franca when it comes to safety and inspired by the Standard Model used in particle physics and recent suggestions from relevant studies, we thought of exploring the possibility to introduce a Standard Safety Model (STASAM). As a first step, we focused on four representative safety and accident models widely used, discussed and debated: the Swiss Cheese Model, AcciMap, Functional Resonance Analysis Method (FRAM) and Systems-Theoretic Accident Model and Processes (STAMP). We reviewed literature which compares the particular models, and we listed the strengths and weaknesses of each as a means to set the grounds for the STASAM. The combinations of these models with a focus to host their advantages and avoiding their disadvantages led to a three-level STASAM. The concept STASAM was used in two random incident investigation reports to assess its applicability and visualisation against the original models. The results of the application along with the STASAM concept were reviewed by three safety professionals and three safety researchers. The comments received were in the positive direction and indicated the potential of establishing an inclusive and commonly accepted safety/accident model. The next research phase will be the additional review of the STASAM and its pilot application to a variety of safety events and systems as a means to test its reliability and strengthen its validity.