Dependency Defence — How to protect against dependent failures

  • Per Hellström
  • Gunnar Johanson
  • Jean-Pierre Bento
Conference paper


Treatment of dependencies in safety analysis is discussed. Important failure causes and coupling mechanisms harming redundant system solutions are presented. Defences to minimize dependent failures are identified and discussed. Control of dependencies by knowledge, good routines, information systems and safety culture is identified as the key factor in avoiding the occurrence of simultaneous unavailability of redundant equipment.


Coupling Mechanism Safety Culture Component Interface Design Review Dependent Failure 
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Copyright information

© Springer-Verlag London 2004

Authors and Affiliations

  • Per Hellström
    • 1
  • Gunnar Johanson
    • 2
  • Jean-Pierre Bento
    • 3
  1. 1.Relcon ABSundbybergSweden
  2. 2.ES-konsult ABSolnaSweden
  3. 3.JPB Consulting ABNyköpingSweden

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