Abstract
Quantitative safety assessment of safety-related control systems consists of many steps, with the creation of a valid mathematical model being the one of most important one. Assumption on constant failure rate of a system leads to numerous approximations that are made in the process of model creation. These approximations need to be coherent with the philosophy of safety assessment and must be discarded if they could artificially increase the safety level of the modelled system. Nevertheless, if probability of the hazardous failure and hazardous failure rate as safety measures are compared, currently used approximations allow to achieve inaccurate or even invalid results of the safety assessment. The scope of the paper covers exact and approximate approach to the safety assessment of a two-channel redundant system structure comprised of dissimilar channels. Outcomes and conclusions of the paper can be immediately applied in many forms of the quantitative safety evaluation.
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References
IEC EN 61508. Functional safety of electrical/ electronic/programmable electronic safety-related systems (2001)
Yun, W.Y., Song, Y.M., Kim, H.: Multiple multi-level redundancy allocation in series systems. In: Reliability Engineering & System Safety, vol. 92, pp. 308–313. Elsevier Ltd., Amsterdam (2007)
Knegtering, B., Brombacher, A.C.: Application of micro Markov models for quantitative safety assessment to determine safety integrity levels as defined by the IEC 61508 standard for functional safety. In: Reliability Engineering & System Safety, vol. 66, pp. 171–175. Elsevier Ltd., Amsterdam (1999)
Rástočný, K., Ilavský, J.: Quantification of the safety level of a safety-critical control system. In: 2010 International Conference on Applied Electronics (AE), September 8-9, pp. 1–4 (2010)
Rouvroye, J.L., Brombacher, A.C.: New quantitative standards: different techniques, different results? In: Reliability Engineering & System Safety, vol. 66, pp. 121–125. Elsevier Ltd., Amsterdam (1999)
Christov, C., Stoycheva, N., Christova, M.: Diversity as a means of safety. In: Mikulski, J. (ed.) TST 2010. CCIS, vol. 104, pp. 308–319. Springer, Heidelberg (2010)
EN ISO 13849. Safety of Machinery. Safety-related Parts of Control Systems (2008)
Rástočný, K., Ilavský, J.: Effects of a periodic Maintenance on the Safety Integrity Level of a Control System. In: Schnieder, E., Tarnai, G. (eds.) Formal Methods for Automation and Safety in Railway and Automotive Systems FORMS/FORMAT 2010. Braunschweig, Part 2, pp. 77–85. Springer, Heidelberg (2010)
Záhradník, J., Rástočný, K., Kunhart, M.: Safety of Railway Interlocking Systems. (In Slovak) EDIS – University of Žilina, Žilina (2004)
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Rástočný, K., Ilavský, J. (2011). What Is Concealed behind the Hazardous Failure Rate of a System?. In: Mikulski, J. (eds) Modern Transport Telematics. TST 2011. Communications in Computer and Information Science, vol 239. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-24660-9_43
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DOI: https://doi.org/10.1007/978-3-642-24660-9_43
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