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A surgical risk reduction approach to reduce global process safety risk: The “PSM gamma-knife”


  • Presented at the American Institute of Chemical Engineers, 2011 Spring Meeting, 7th Global Congress on Process Safety, Chicago, Illinois, March 13–16, 2011


Businesses with more than one site strive to minimize operational variability across their entire organization. However, uniformly implementing company-wide standards is difficult because each site maintains its own personality—its own culture. When a business strives to reduce its global process safety risk, a significant incident that exposes a particular site's weakness may result in a simple corporate decision forcing all sites to implement the same process safety improvement. This article shares the basic concept and the novel use of a risk minimization tool, commonly used to reduce financial risks in an investment portfolio, to help decision-makers minimize their multisite, global process safety risk without adding undue stress on the rest of the organization. This approach helps quantify each individual site's process safety risks into a global business process safety risk model, uses a Monte Carlo simulation to determine which site-specific factors contribute the most to the overall business risk, and then helps decision-makers prioritize and choose site-specific risk reduction efforts that minimizes the global risk. The global process safety risk reduction model used to show how to use this approach is based on a simplified risk equation containing site-specific terms for frequency, consequence and operational discipline. Often the most contentious term in risk estimating is the frequency, especially with significant scenarios that have never happened before and, hence, have a very low likelihood. The beauty of the Monte Carlo simulation is that the user can account for the uncertainty in the frequency by choosing a frequency probability function based on a range of possible best- to worst-case consequence scenarios. From the surgical perspective, a person (the whole organization) with cancer is often adversely affected when treated with chemotherapy. The results from this approach, using the image of a “PSM Gamma Knife,” show how selective site-specific risk reduction treatments specifically address each site's process safety risk to help reduce the overall risk without adversely affecting the health of the whole organization. © 2012 American Institute of Chemical Engineers Process Saf Prog, 2012