Safety Cases and Their Role in ISO 26262 Functional Safety Assessment

  • John Birch
  • Roger Rivett
  • Ibrahim Habli
  • Ben Bradshaw
  • John Botham
  • Dave Higham
  • Peter Jesty
  • Helen Monkhouse
  • Robert Palin
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8153)


Compliance with the automotive standard ISO 26262 requires the development of a safety case for electrical and/or electronic (E/E) systems whose malfunction has the potential to lead to an unreasonable level of risk. In order to justify freedom from unreasonable risk, a safety argument should be developed in which the safety requirements are shown to be complete and satisfied by the evidence generated from the ISO 26262 work products. However, the standard does not provide practical guidelines for how it should be developed and reviewed. More importantly, the standard does not describe how the safety argument should be evaluated in the functional safety assessment process. In this paper, we categorise and analyse the main argument structures required of a safety case and specify the relationships that exist between these structures. Particular emphasis is placed on the importance of the product-based safety rationale within the argument and the role this rationale should play in assessing functional safety. The approach is evaluated in an industrial case study. The paper concludes with a discussion of the potential benefits and challenges of structured safety arguments for evaluating the rationale, assumptions and evidence put forward when claiming compliance with ISO 26262.


Safety cases safety arguments ISO 26262 automotive safety 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • John Birch
    • 1
  • Roger Rivett
    • 2
  • Ibrahim Habli
    • 3
  • Ben Bradshaw
    • 4
  • John Botham
    • 5
  • Dave Higham
    • 6
  • Peter Jesty
    • 7
  • Helen Monkhouse
    • 8
  • Robert Palin
    • 9
  1. 1.AVL Powertrain UK LtdBasildonUK
  2. 2.Jaguar Land RoverCoventryUK
  3. 3.University of YorkYorkUK
  4. 4.TRW ConektSolihullUK
  5. 5.Ricardo UK LtdCambridgeUK
  6. 6.Delphi Diesel SystemsUK
  7. 7.Peter Jesty Consulting LtdTadcasterUK
  8. 8.Protean Electric LtdSurreyUK
  9. 9.MIRA LtdNuneatonUK

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