Centre of Competence for Mass Transit AME, Bombardier Transportation, Kingston, Canada.
The concept of Safety Integrity Level (SIL) has been developed within different systems of standards (IEC 61508, EN50129 and DEF-STAN 00-56). These standards are applied in different areas: control technology (IEC 61508), railway technology (EN50128 and EN 50129), and defense technology (DEF-STAN-00-56). Nowadays, a lot of the mass transit turnkey projects around the world demand the contractors to follow CENELEC standards and SIL concept for the safety function implementation. Although the concept of SIL is mentioned in these standards, the interpretation of the concept of SIL in these standards is not consistent and unequivocal. This paper is written to elaborate the anomalies of SIL interpretation among these various standards in order for safety engineers to obtain a more detailed view on the concept of SIL over these standards.
Keywords- Safety integrity level (SIL), CENELEC standard, Safety instrumented system (SIS), Hardware fault tolerance (HFT), Common cause failure (CCF).
Li, J. (2018). SIL Implementation on Safety Functions in Mass Transit System. International Journal of Mathematical, Engineering and Management Sciences, 3(3), 258-270. https://dx.doi.org/10.33889/IJMEMS.2018.3.3-018.
Conflict of Interest
Andrews. J. (2010, January). Introduction to fault tree analysis. In Reliability and Maintainability Symposium (RAMS), 2010 Proceedings – Annual (pp.7-8). IEEE.
BS EN 50128 Railway applications – Communications, Signalling and Processing Systems – Software for Railway control and protection systems, British Standards Institute.
BS EN 50129 Railway applications – Communications, Signalling and Processing Systems – Safety related electronic systems for signalling, British Standards Institute.
BS EN50126 Railway applications – The specification and demonstration of dependability. Reliability, Availability, Maintainability and Safety (RAMS), British Standards Institute.
Department of Defense (US), MIL-STD-882: System Safety Program Requirements. 1993 (version C), 2000 (version D).
Engineering Safety Management Issue 3, Yellow Book 3, Volumes 1 and 2, Fundamentals and Guidance (p. 9-3). Published by Railtrack on behalf of the UK rail industry.
IEC 61508, Functional Safety of Electrical /Electronic / Programmable Electronic Safety Related Systems, Parts 1-7, International Electro – technical Commission, Geneva, Switzerland (1999-2001).
Klion, J. (1997). System periodically maintenance. In A Redundancy Notebook (pp.29-88). Rome Air Development Center Publishing.
Langeron, Y., Barros, A., Grall, A., & Bérenguer, C. (2008). Combination of safety integrity levels (SILs): A study of IEC61508 merging rules. Journal of Loss Prevention in the Process Industries, 21(4), 437-449.
Military Standard (2005). MIL-HDBK-338B Military Handbook Electronic Reliability Handbook, Notice 2 (pp.334-350). Air Force Research Laboratory Information Publishing.
Ministry of Defense (UK), DEF STAN 00-56, Safety Management Requirements for Defense Systems, Part 1 and 2, Dec. 1996.