What to Do When Nothing Has Happened?

  • Type:
    Conference Presentation
  • Conference Type:
    Global Congress on Process Safety
  • Presentation Date:
    March 15, 2011
  • Skill Level:
    Intermediate
  • PDHs:
    0.50

Share This Post:

You will be able to download and print a certificate for PDH credits once the content has been viewed. If you have already viewed this content, please click here to login.

Often during a Layer of Protection Analysis (LOPA) or a Quantitative Risk Analysis (QRA) study, historical information indicates no occurrences of a particular undesired event in the plant or system. The analyst must decide on an appropriate measure of the frequency of the undesired event. The simple reply that the frequency or rate is zero because the event has never happened is sometimes heard by the analyst during review meetings. Previously, Freeman presented a summary of twelve statistical tools that have been proposed to handle this problem. This paper expands on the previous work and adds another statistical tool for developing a measure of the frequency or failure rate of an event when the historical information includes no occurrences of the event. Guidance is presented on methods to incorporate historical information of no failures into a LOPA or QRA study. Examples are presented using the recommended methods for the estimation of initiating event frequencies where historical information indicates that the initiating event has not happened.

Please note that due to the visual quality of this paper, there is no charge for it. The information is still valuable hence we are posting it here.
Presenter(s): 

Checkout

Checkout

Do you already own this?

Log In for instructions on accessing this content.

Pricing

AIChE Members $15.00
AIChE Undergraduate Student Members Free
AIChE Graduate Student Members Free
Non-Members $25.00