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ASIL Decomposition: The Good, the Bad, and the Ugly
Technical Paper
2013-01-0195
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
ASIL decomposition is a method described in the ISO 26262 standard for the assignment of ASILs to redundant requirements. Although ASIL decomposition appears to have similar intent to the hardware fault tolerance concept of IEC 61508-2, ASIL decomposition is not intended to reduce ASIL assignments to hardware elements for random hardware failures, but instead focuses on functions and requirements in the context of systematic failures. Based on our participation in the development of the standard, the method has been applied in different ways in practice, not all of which are fully consistent with the intent of the standard. Two potential reasons that may result in the use of “modified” ASIL algebra include the need of OEMs to partition a system and specify subsystem requirements to suppliers and the need for designers to construct systems bottom up. Constructing systems bottom up has the goal of achieving a target system level ASIL from component elements that have some notion of ASIL already associated with them. In this paper, we examine the origins of ASIL decomposition in the ISO 26262 standard, potential benefits and limitations of the approach, and by examining publications on this subject, how it is currently being applied in industry programs.
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Citation
D'Ambrosio, J. and Debouk, R., "ASIL Decomposition: The Good, the Bad, and the Ugly," SAE Technical Paper 2013-01-0195, 2013, https://doi.org/10.4271/2013-01-0195.Also In
References
- ISO 26262 Functional Safety - Road Vehicles November 2011
- IEC 61508 Functional safety of electrical/electronic/programmable electronic safety-related systems 2 nd 2010
- Piovesan Andrea and Favaro John Experience with ISO 26262 ASIL Decomposition Presentation at Automotive SPIN Milano Italy February 2011
- Webinar Mahindra Satyam Automotive Functional Safety with ISO 26262 January 2012 http://www.mahindrasatyam.com/events/documents/ISO26262_webinar_presentation.pdf
- Cheon J.S. , Kim J.S. , Jeon J.H. , Lee S.M. Brake By Wire Functional Safety Concept Design for ISO/DIS 26262 Paper 2011-01-2357, SAE World Congress April 2011
- Kalmbach J. , Wenzel T. , and Fassl M. Recipe for Safe Software Vector Technical Article November 2010
- Ward David The uses and abuses of ASIL decomposition in ISO 26262 Presentation at System Safety Conference Edinburgh UK October 2012
- ISO 26262 Part 10 (FDIS) Functional Safety - Road Vehicles: Guideline on ISO 26262 July 2012
- Ericson Clifton II Hazard Analysis Techniques for System Safety Wiley 2005