Human Factors in the Railway Sector - Coursework Example

Name Course name Name of Institution Instructor’s name Date Abstract. The European railway standards that are being used nowadays highlights ways in which the railway safety systems have been influenced by the human factors. Transportation plays an important role in the economic development of a country. Of all other similar sectors, this one cannot be overlooked since there are great benefits to reap from it. Rail transportation has proved to be very useful in the transportation of both passengers and bulky goods. However, the combination of human factors in handling the functional safety system in the railway technology has been reduced in the practices of the engineers. The reports takes into consideration human factors in various phases in its life cycle and also in the many risks in the railway operation and designs straight-forward working system model which have been brought about to structure the factors that are very crucial on the performance of humans and to create practical cause-and-effects diagram. Besides this, the mechanisms set up for safety and are being practised currently in railways should be revised, this is mainly due to their efficiency in terms of the human-barrier-interactions. The report will also put into consideration the integration of the performance of the humans into the engineering practice and the assessments of the railway safety. Keywords Safety, human error, barriers, risk analysis. Introduction. In the western countries, the consideration of the human factors has not been looked into keenly. Human factors cannot be said to have a long history. This has resulted to a majority of the accidents being accounted to human error. Out of date, automation and the utilisation of permanent human error probabilities used to analyse the risks are still available. This report looks into railway engineering and brings the point of the need to integrate human factors with the idea in mind of reducing the human errors that currently happen often. This is one way that can easily increase the efficiency of the workers, reduce risks and also minimise accidents associated to human errors. Body. The human factors in the railway system life cycle. The most famous and very important for the design of railway system and technical components EN 50126-1 [3], requires to be integrated with the human factors. The standard usually gives very little information on the ways necessary for the integration even after the emphasis on the benefits that are there upon the integration of the human factors of the railways system’s stuff. This has been a major challenge that has faced this sector for a very long period and a lot of efforts are needed to ensure that this is implemented. The principle model of maintainability, availability, reliability and more important safety. That has been availed in the levels was brought about by Anders [15]. The figure below openly indicates that the human factors if shown in a diagram, come up in the critical phases of it cycle. These are the basic factors that build up the human factors. For any system to be effective, the human factors cannot be ignored. Human factors create a great link and integration in any effective working system. Many human errors can easily be avoided if this is taken into consideration. Figure 1.0 Railway System Life Cycle The figure above shows the human factors in the railway safety system life-cycle (adopted from [15] the workplace of the humans has been indicated in the sharp end, the operational rail system and the risks that are closely related to the safety has always been the duty of the engineers to shape them, also the operator himself and the employer. This indicates that the people in charge of designing at the operating company are not positioned at the manufacturer. In the railway industries, it is the mandate of the employers to set up the necessary requirements. The people who also design do the evaluation of the risk that evolves from the tasks of the operator tends to have a very limited scope, the designer can also decide to conduct a safety assessments, to consider the human factors into the operating system. The engineer to design should have a stable perspective in order to carry out an evaluation risk for the human-machine-system, the operator should be in a position to view risk control from a very flexible point of view [14]. Qualitative risk analysis. EN 50129 [4] is the set European standard that creates the need to have a qualitative analysis of risk for safety-related railway systems. Any hazard has to be identified early enough and the resulting risk should be correctly estimated. This is the only sure way of creating an active and working system. Sometimes the might not be negligible therefore it calls for it to be proven that the final product meets the set safety requirements. Usually to be on the safer side, the associated tolerable risk rate must be much higher than that of the actual hazard rate of a safety measured function. This creates an excellent chance to put into place the technical components and estimations can sufficiently be made. It is crucial if the railways companies can acquire human liability by simply grouping of an estimate of the probability of human error. The most important and thing to consider for rail transport is combining human performance and technical reliability. This is simply because most functions related to safety are implemented by bringing together of both the human factors and the technical systems. Resume proposals. Different countries in Europe had different safety assessment and approval processes during the harmonisation [2]; there was the need to create an opportunity for incorporating human contribution to the system security and performance. This is one of the ways that helps to establish technical but also human interoperability. The most important standard for railway dependability engineering targets and puts a lot of focus at the combination of the human factors leaving aside the approaches. The inclusion of human error into the classic risk analysis techniques has provided a better way assess the human contribution. When this method is put into place and implemented, there is a danger to degrade the human operator to being undesirable and prone to errors. However, the broad acknowledgement of the levels of standards in the railway sector creates more need in practice to incorporate technical and human performances in a quantitative way. Human error in quantitative risk analysis. Many are times the rail practitioners face challenges in the incorporation of the human reliability when coming up with a classic risk assessment into the methods of analysis. This is usually mainly due to lack of the necessary human data for the human error occurrences in the railway domain. More adapted risk analyses refer to the values for human error in rail transport published by [11]. 18 fixed probabilities are portrayed in dependence of stress level, surrounding conditions and Rasmussen’s three levels of behaviour: knowledge-based, rule-based and skill-based [9], [5]. It clearly indicates that not even Hinzen’s values are sufficiently proven to be authentic for the railway transport, nor do the statistics of the accidents gives a comprehensive data to derive human error probabilities. The possibilities of any given working conditions to be obtained there should be the incorporation of the classic approach that mainly uses the human reliability assessment (HRA). Existing techniques for human reliability assessment. The procedures that are usually followed for most of the HRA approaches are purposeful to carry out a qualitative analysis of the task with the aim of assessing the likelihood of possible human errors. The human errors qualification methods can be put in place more often. The technique Analysis of Consequences of Human Unreliability (ACIH) [13] stands in place for a non-probabilistic technique for human reliability assessment. Human error taxonomy by Reason [10] indicates that the shapes are more than one shape for the malfunctions made by the humans. This helps to make the work easier, efficient and very productive. Human variability and resilience. The challenges that have faced over the past years have forced to bring safety and human factors together. The knowledge of understanding human variability as a capability and not as a threat. Coming to know security as the presence of adaptability but not absence of weak points and anthropogenic mistakes and errors is referred to as resilience engineering [6]. The accident analysis method FRAM developed by Hollnagel [7] has also been put in place in the railway domain [1]. Structure for performance shaping factors. This part will mainly deal with the structure for performance shaping factors that can be applied to a railway system .The approach is largely based on a model on working environments. What the structure tries to put forward is to visualize psychologist’s perspectives and engineering in a manner that is very straight forward and very easy to understand the phenomena in a working system is mainly influenced by the human factors. They are set apart into variables that the railway engineer can create some modifications where necessary. Figure 2.0 below represents the shaping factors and working models of the system. The centre indicates the model of a working system that clearly the work system cores which is the interaction of human, instruments and tasks. The values that have been set represented by the physical, personal and organisational factors, such as the performance shaping factors. Such as the performance shaping factors in many times usually have a direct impact on the individual factors. For instance training usually has a direct bearing on the skills of the employees. Figure 2.0 Working Models and Shaping Factors All the factors that are the most influential usually at the top and bottom are mainly less dynamic and have a direct influence and impact on the work system core. The horizontal axis in the diagram above usually represents the work system at the moment of operation. Through the work system core, Inputs of information often change dynamically from time to time. Influences on human performance. It is easy to visualise the performance of humans from the outside factors in chains of action. There is the following weighting of connections which has the role in representing the assessment of the extent of influence of some particular performance shaping factors and adds weight the severity of the conditions that favour errors. The semi-quantitative assessment is an undertaking either by both human factors and rail expert judgement or with the help of simulations together with the human factors studies in the relevant environments. Figure 3.0 Performance Shaping Factors Human-barrier-interaction in railway systems. Barriers are those factors that have the role in representing the safety mechanisms that are put into place to stop the undesired events from taking place and also prevention from the possible consequences. The most common grouping of barriers brings out the difference between the material boundaries being; physical in the system, functional barriers creating dependencies, symbolic and immaterial barriers, the latter both being for example signs or rules [7]. A three-step structure is usually put in place to enable classification of safety barriers in terms of a process model. The prevention of initial events that are not desired and should not take place are catered for in the obstacles of prevention. Barriers of correction have a significant role to facilitate the recovery of the situation, barriers that lessen the severity of the consequences are called the boundaries of containment, [12]. Due to the dependency of human actions, these barrier systems can be estimated as being medium or less efficient [6]. The analyzation of the human-barrier-interaction needs a profound manner for it to be successful. Therefore, the approach is not supposed to pay considerable attention to the limitations and violations that are usually interpolated as barrier removal in [8] but should rivet a lot of focus at the general human performance. For this ideal be active in a railway system, there should be put in place a comprehensive barrier identification procedures. Up to now there two initial approaches that are available in the literature. A good example is considering the protection against over-speed in the task of driving a train. Many are times that barriers allow the study of consequences of malfunctioning as obstacles that can usually secure or overlap each other. Conclusion. The primary focus of the paper was to bring out the need and necessity for the integration of the human factors in the various phases of the railway system’s life cycle. This is one of the factors that can quickly reduce the risks that are very likely to occur and at the same time improve efficiency. Provision of training to the working stuff in a railway system adds their knowledge and skills and this makes them efficient and competent. Rail transport needs significant considerations since stupid mistakes can be fatal leading to mass loss of life, goods and resources. This is a sector that significantly contributes to the upward mobility of the economies of most countries in the world and should not be neglect. Sophisticated technology should also be taken into consideration besides upgrading of the current technology. References. [1] F. Belmonte, “Automatic Train Supervision safety assessment by Functional Resonance Accident Model,” 3rd European Conference on Rail Human Factors. 2009. [2] L. Cassir, C Harmonization of risk acceptance criterion in Common Safety Methods, SiT – Safety in Transportation, Brunswick.2008, [3] CENELEC (ed.), EN 50126-1, Railway applications. The specification and demonstration of reliability, availability, maintainability and safety (RAMS). Basic requirements and generic process, CENELEC-Corrigendum, 2006. [4] CENELEC (ed.), EN 50129, Railway applications – Communication, signalling and processing systems – Safety related electronic systems for signalling, 2003. [5] Feldmann, F., Hammerl, M. and Schwartz, Questioning human error probabilities for railways. 3rd IET International Conference on System Safety, Birmingham.2008. [6] Hollnagel, E.Barriers and Accident Prevention, (Ashgate Publishing), 2005. [7] Hollnagel, E., Woods, D., Leveson, N. 2006, Resilience Engineering: Concepts And Precepts (Ashgate Publishing), 2004. [8] Polet, P., Vanderhaegen, F., Wieringa, A, Theory of Safety-Related Violations of System Barriers, Cognition, Technology & Work, 4, 171–179, 2004. [9] Rasmussen, J. Skills, rules, and knowledge; Signals, signs, and symbols, and other distinctions in human performance models. IEEE Transactions on Systems, Man, and Cybernetics, 13 (3) 257–266, 1983. [10] Reason, J., Human error, (Cambridge University Press, New York), 1990. [11] RSSB (ed.), Rail-specific HRA technique for driving tasks – User Manual, 2005. Schwartz, S.; Pelz, M Safety Layers at Level Crossings. 10th World Level Crossing Symposium (Safety and Trespass Prevention), Paris, 2008. [12] Sklet, S, Safety barriers: Definition, classification, and performance, Journal of Loss Prevention in the Process Industries 19, 494–506, 2006. [13] Vanderhaegen, F, A non-probabilistic prospective and retrospective human reliability analysis method – application to railway system, Reliability Engineering and System Safety 71 (1) 1-13, 2001. [14] Vanderhaegen, F. The Benefit-Cost-Deficit (BCD) model for human error analysis and control, 9th IFAC/IFORS/IEA symposium on Analysis, Design, and Evaluation of Human-Machine Systems, Atlanta, 2004. [15] Anders, G. Railway System Life Cycle, New York, 2004. Read More

These are the basic factors that build up the human factors. For any system to be effective, the human factors cannot be ignored. Human factors create a great link and integration in any effective working system. Many human errors can easily be avoided if this is taken into consideration. Figure 1.0 Railway System Life Cycle The figure above shows the human factors in the railway safety system life-cycle (adopted from [15] the workplace of the humans has been indicated in the sharp end, the operational rail system and the risks that are closely related to the safety has always been the duty of the engineers to shape them, also the operator himself and the employer.

This indicates that the people in charge of designing at the operating company are not positioned at the manufacturer. In the railway industries, it is the mandate of the employers to set up the necessary requirements. The people who also design do the evaluation of the risk that evolves from the tasks of the operator tends to have a very limited scope, the designer can also decide to conduct a safety assessments, to consider the human factors into the operating system. The engineer to design should have a stable perspective in order to carry out an evaluation risk for the human-machine-system, the operator should be in a position to view risk control from a very flexible point of view [14].

Qualitative risk analysis. EN 50129 [4] is the set European standard that creates the need to have a qualitative analysis of risk for safety-related railway systems. Any hazard has to be identified early enough and the resulting risk should be correctly estimated. This is the only sure way of creating an active and working system. Sometimes the might not be negligible therefore it calls for it to be proven that the final product meets the set safety requirements. Usually to be on the safer side, the associated tolerable risk rate must be much higher than that of the actual hazard rate of a safety measured function.

This creates an excellent chance to put into place the technical components and estimations can sufficiently be made. It is crucial if the railways companies can acquire human liability by simply grouping of an estimate of the probability of human error. The most important and thing to consider for rail transport is combining human performance and technical reliability. This is simply because most functions related to safety are implemented by bringing together of both the human factors and the technical systems.

Resume proposals. Different countries in Europe had different safety assessment and approval processes during the harmonisation [2]; there was the need to create an opportunity for incorporating human contribution to the system security and performance. This is one of the ways that helps to establish technical but also human interoperability. The most important standard for railway dependability engineering targets and puts a lot of focus at the combination of the human factors leaving aside the approaches.

The inclusion of human error into the classic risk analysis techniques has provided a better way assess the human contribution. When this method is put into place and implemented, there is a danger to degrade the human operator to being undesirable and prone to errors. However, the broad acknowledgement of the levels of standards in the railway sector creates more need in practice to incorporate technical and human performances in a quantitative way. Human error in quantitative risk analysis.

Many are times the rail practitioners face challenges in the incorporation of the human reliability when coming up with a classic risk assessment into the methods of analysis. This is usually mainly due to lack of the necessary human data for the human error occurrences in the railway domain. More adapted risk analyses refer to the values for human error in rail transport published by [11]. 18 fixed probabilities are portrayed in dependence of stress level, surrounding conditions and Rasmussen’s three levels of behaviour: knowledge-based, rule-based and skill-based [9], [5].

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