A Modified Hazop Methodology For Safety Critical System Assessment

  • D. J. Burns
  • R. M. Pitblado


The concept of a Safety Lifecycle for Programmable Electronic System (PES) based systems has previously been suggested by the Working Group for an IEC draft standard dealing with safety-related software. The starting point in such a Lifecycle is Hazard Analysis which may be performed using a variety of accepted tools, including Fault Tree Analysis (FTA), Failure Modes, Effects and Criticality Analysis (FMECA) and Hazard and Operability studies (HAZOP). This paper describes work carried out to extend the standard FMECA and HAZOP approaches to suit the analysis of Programmable Electronic Systems, based on a number of case studies.


Hazard Analysis Design Intent Hazardous State Fault Tree Analysis Fault Tree Analysis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag London Limited 1993

Authors and Affiliations

  • D. J. Burns
    • 1
  • R. M. Pitblado
    • 1
  1. 1.DNV TechnicaLondonUK

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