Probability of Failure (POF)

Last update: Jan 13, 2017

Probability of Failure (POF) is likelihood that a piece of equipment will fail at a given time and an important part of effective risk analyses. POF is half of the equation when determining risk as part of Risk Based Inspection (RBI) methodology. The POF, calculated together with the Consequence of Failure (COF), helps operators establish the risk level for a particular piece of equipment and set inspection intervals based on the calculated risk.  

POF is calculated for individual pieces of equipment by looking at the potential damage mechanisms it could be susceptible to, a general frequency of failures, and management system factors.  More details on POF are provided in the American Petroleum Institute's Recommended Practice 580 - Risk Based Inspection (RBI), which contains directions on developing, implementing and maintaining an effective RBI program.[1]

References

  1. http://www.weibull.com/hotwire/issue151/hottopics151.htm

 

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