The systematic integration of Human Factors into safety analyses: an integrated engineering approach

The performance of the human reliability analysis (HRA) and integration of its outcomes into quantitative risk assessment schemes remains quite a difficult and complex task to perform. Even worse is the assessment of organisational reliability assessment. The reasons of this difficulty mainly lay on the absence of a generically accepted paradigm that enables engineers to include systematically human and organisational factors (H&OF) into the analysis. Broadly speaking, engineering approaches very often account for error of omission forgetting the errors of commission (EOC), and, on top of that, they do not make any macro distinction between pre- and post-initiating human failures. This paper offers a paradigm on how to integrate H&OF into safety analysis by means of the recursive operability analysis (ROA), which has been adapted to accommodate H&OF, and renamed integrated recursive operability analysis (IROA). By means of a practical example, the method will illustrate how to account for H&OF in a systematic and consistent manner using an engineering approach. The paper will even provide a paradigm for the construction of integrated fault trees consistent with the IROA framewor

Risk Assessment Techniques for Civil Aviation Security

Following the 9/11 terrorists attacks a strong economical effort was made to improve and adapt aviation security, both in infrastructures as in airplanes. National and international guidelines were promptly developed with the objective of creating a security management system able to supervise the identification of risks and the definition and optimisation of control measures. Risk assessment techniques are thus crucial in the above process, since an incorrect risk identification and quantification can strongly affect both the security level as the investments needed to reach it. The paper proposes a set of methodologies to qualitatively and quantitatively assess the risk in the security of civil aviation and the risk assessment process based on the threats, criticality and vulnerabilities concepts, highlighting their correlation in determining the level of risk. RAMS techniques are applied to the airport security system in order to analyse the protection equipment for critical facilities located in air-side, allowing also the estimation of the importance of the security improving measures vs. their effectiveness

A Data-Driven Framework to Model Physical Fatigue in Industrial Environments Using Wearable Technologies

Industry 4.0 is the tendency towards automation and data exchange in manufacturing and the process sector. However, many manual material handling and repetitive operations can still cause the operators fatigue or exhaustion. Once the operator experiences physical fatigue, their performance decreases. The consequences may result in reduced production quality and efficiency and increased operational human errors that could give rise to incidents and accidents. Over time, physical fatigue can result in more adverse effects for the operators, such as Chronic Fatigue Syndrome (CFS) and Work-related Musculoskeletal Disorders (WSMD). For this reason, from an occupational health and safety point of view, the operator’s hysical fatigue must be managed. The increasing availability of wearable devices combined with health information can provide real-time measuring and monitoring of physical fatigue in the operational environment while minimally influencing the primary job. This paper presents a physiological signal-based approach using a non-intrusive wristband for continuous health monitoring to predict physical fatigue in industrial-related tasks. These data are used as input to classification algorithms to detect physical fatigue. Accurate and real-time physical fatigue detection helps to improve operator safety and prevent work accidents. Future work will deploy the model in a real-world environment in the industry

Simplified Model of the Internal Atmosphere of Flammable Liquid Tanks in Case of Air Inlet from a Pressure Safety Valve

Storage of flammable liquids is a common activity in many industrial domains. A history of accidents shows that liquid storage has been involved in several critical accidents due to the large amount of hazardous substances potentially involved in the incident. Safe storage of flammable liquids is often guaranteed through blanketing of the internal atmosphere of the tank through the introduction of an inert gas, usually nitrogen. A double action pressure safety valve is often installed on the tank to protect the tank from damage in the event of overpressure or depression. In case of depression, an inert gas, usually nitrogen, is fed to the vapor space of the tank to maintain the vapor composition outside of the flammability limits. In case of lack of nitrogen, the opening of the pressure safety valve allows air to enter. The entry of air, especially if prolonged, can bring the atmosphere inside the tank to explosive conditions. This paper presents a simplified model for the estimation of the internal composition of the tank following the entry of air due to the opening of the pressure safety valve, following the process of fluid removal in case of lack of nitrogen. The model also allows the estimation of how much liquid can be safely removed. The simplified model can analyze both the case of a single tank and a tank farm

Risk awareness versus risk assessment in manufacturing: A field study

Risk assessment in manufacturing work environments gives a relevant contribution to health and safety management for the operators: hazards are identified, and the associated risks are quantified in order to promote the risk mitigation and to improve the safety level for all the workers involved. In this paper the relation between the risk assessment performed by Safety managers and workers' risk awareness is investigated using as case study a manufacturing plant (heavy vehicles) in Northern Italy. Risks are assessed with a set of widely used procedures and methods that return a level of risk related to each workplace. According to the most recent Italian regulation on safety at works (D.Lgs. 81/08) each worker has to be informed and trained about all risks he would be exposed to during her/his working activity. Operators are the final stakeholders of this process that started with a risk assessment performed by experts and ended with a transmission of information involving safety, personal health and working behaviour. To compare risk assessment and risk awareness, a field study was performed with more than 50 workers surveyed on their personal awareness of level of risk associated to their working task. The comparison highlighted significant miss-matches that are here discussed. To solve this miss-match a review of safety information methods and safety training for workers was identified as countermeasure

Using Field Data for Energy Efficiency Based on Maintenance and Operational Optimisation. A Step towards PHM in Process Plants

Energy saving is an important issue for any industrial sector; in particular, for the process industry, it can help to minimize both energy costs and environmental impact. Maintenance optimization and operational procedures can offer margins to increase energy efficiency in process plants, even if they are seldom explicitly taken into account in the predictive models guiding the energy saving policies. To ensure that the plant achieves the desired performance, maintenance operationsandmaintenanceresultsshouldbemonitored,andtheconnectionbetweentheinputsand theoutcomesofthemaintenanceprocess,intermsoftotalcontributiontomanufacturingperformance, should be explicit. In this study, a model for the energy efficiency analysis was developed, based on cost and benefits balance. It is aimed at supporting the decision making in terms of technical and operationalsolutionsforenergyefficiency,throughtheoptimizationofmaintenanceinterventionsand operational procedures. A case study is here described: the effects on energy efficiency of technical and operational optimization measures for bituminous materials production process equipment. The idea of the Conservation Supply Curve (CSC) was used to capture both the cost effectiveness of the measures and the energy efficiency effectiveness. The optimization was thus based on the energy consumption data registered on-site: data collection and modelling of the relevant data were used as a base to implement a prognostic and health management (PHM) policy in the company. Based on the results from the analysis, efficiency measures for the industrial case study were proposed, also in relation to maintenance optimization and operating procedures. In the end, the impacts of the implementation of energy saving measures on the performance of the system, in terms of technical and economic feasibility, were demonstrated. The results showed that maintenance optimization could help in reaching an energy costs recovery equal to the 10% of the total costs for an electric motor system

Preliminary risk assessment of ecotoxic substancesaccidental releases in major risk installationsthrough fuzzy logic

In the present work a fuzzy logic model to preliminary assess the risk of accidental releases of ecotoxic substances in hazard plants has been developed. The methodology is based in three steps, the characterization of the hazardousness of the substance, the delimitation of the soil and groundwater vulnerability and the identification of the protective and preventive measures of the plant. The tool has been tested with a set of storage yards of ecotoxic substances, mainly oil, in the Regione Piemonte area (Italy). The results obtained are in good agreement with the real situation of the surveyed storage yards. Thus, by using this methodology it is possible to preliminary assess the risk from uncertain data.Peer ReviewedPostprint (published version

Operators’ risk awareness towards operations’ risk assessment: a field study in the motor vehicle field

Purpose: The purpose of the research was to verify if there was an alignment between the risk assessed and the risk perceived or if some inconsistencies arise that could affect the safety of the operators. In fact, eventual inconsistencies should be analysed, interpreted and managed to maximise the information and training process, if needed. Design/methodology/approach: The adopted approach in this work relies on the collection of the perception of the operators about the level of risk in a work environment and its comparison with the level of risk assessed by the company. The collection of data was performed through a survey designed ad hoc, subministrated to all the workers in the area under study, being them involved in the production and in the maintenance. The survey’s structure and aim were described to the operator by the researchers and returned by the operators in a voluntary and anonymous way. Findings: The information collected allowed identifying a gap between the risk assessed and the risk perceived by the plant operators. For example, for the use of personal protective equipments, the data highlighted a discrepancy between the knowledge about their need and the behaviour in using them, which resulted in the revision of both communication and training processes, with the adoption of a more participatory approach. Originality/value: The originality of the work is in the data set, originally collected for this study, in the data collection form, also devised specifically for the case under study, despite it can be easily adapted for other work environment, and in the purpose itself, aimed at pushing risk assessment towards a personalised and adaptive approach

Human-in-the-Loop Configurations in Process and Energy Industries: A Systematic Review

The human-in-the-loop performance evaluation is an area of growing interest in industries where safety-critical systems are in place. Concerns here are due to the increasing complexity of automation, new technologies for control, and safety. Because, unlike a more traditional approach to evaluating the human and the system they work with, human-in-the-loop gives a holistic view of their interaction (human, automation or artificial intelligence) and dynamics. It also emphasizes adapting the technology or automation to the human, being central, considering certain factors like risk. Therefore, there is a need to identify the relevant factors, novel measures and methods or improvements on existing methods that can be adapted for this field of research. This paper intends to present an overview of human-in-the-loop in the process and energy industries by presenting a literature summary highlighting current factors and measures, methods, gaps, solutions and future work. Experimental (13) and observational (11) studies have been reviewed for results. It was observed that new factors, measures and techniques are currently being explored to fill some of the current gaps for the human-in-the-loop, for example, during performance assessment new methods and modalities have been adopted such as eye tracking and electroencephalography methods. The results and open questions from the papers reviewed and possible future research opportunities are presented and discussed in this paper

Multivariable Based Decision-making for the Maintenance Strategy of Process Equipment

Nowadays, several pieces of equipment are running over their expected life-time. An equipment revamping could solve the situation, but, it is often not possible for economical reasons, regulatory constraints, etc.. The aging of the equipment can also cause safety problems: between 1980 and 2006, the Health and Safety Executive estimated that around 28% of the major incidents occurred in the period, corresponding to 96 accidents, could be traced back to plant aging. These accidents costed more than 17,000,000 € (Horrocks et al., 2010). A correct maintenance of the equipment can extend the plant life, increase the plant efficiency and maintain an adequate level of safety. Plant management can choose among different maintenance strategies. The choice can be influenced by parameters as: the maintenance cost, the equipment condition before the maintenance, the lack of production cost, the safety of the operator during the maintenance and during the normal operations. In this paper, a multivariable Fuzzy approach is proposed in order to support the decision between different maintenance strategies through the analysis of their peculiarities, helping the management to weight the pros and cons of the alternatives. This approach is applied to a case study related to the maintenance of process equipment: it highlighted that the full refurbishment of a turbine blades system is a maintenance approach as valid as the current maintenance procedure, while the adoption of new technologies resulted not convenient