Risk Mitigation on Ammonia and Methanol Primary Steam Reformers using Retrofitted Safety Instrumented Systems: A Comparative Cost-benefit, Risk-informed Study

  • Dimitrios Karydas
  • Glenn Mahnken
Conference paper


Primary steam reformers used in the “front end” of ammonia and methanol process plants are subject to severe property damage and extended production downtime in case of accidents initiated by abnormal deviations in certain process parameters. Safety instrumented systems can be installed on primary reformers to help reduce the frequency of such process upsets. After conducting a hazard analysis to identify the critical process parameters in a primary reformer, the appropriate level of reliability for instrumented safeguards should be determined using known risk ranking methods. A risk-informed cost-benefit analysis tool can then be deployed to compare alternative safety instrumentation systems, as demonstrated by an example in this paper.


Steam Reformer International Electrotechnical Commission Safety Function Risk Ranking Critical Process Parameter 
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Copyright information

© Springer-Verlag London 2004

Authors and Affiliations

  • Dimitrios Karydas
    • 1
  • Glenn Mahnken
    • 1
  1. 1.FM GlobalNorwoodUSA

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