LOPA as a PHA Complementary Tool: A Case Study

Abstract

Abstract This article presents an example of the use of a risk assessment technique called Layers of Protection Analysis (LOPA) as a complementary technique to be employed after a Preliminary Hazard Analysis (PHA). The article shows a case of study from an offshore exploration and production unit type Floating Production Storage and Offloading System (FPSO). The results showed that the use of LOPA technique resulted in a better accuracy in estimating the risk, through the initial adoption of the risk tolerance criteria, reducing the subjective judgments originated from the qualitative classification of the accidents sceneries that happened during the elaboration of PHA. Furthermore, the study results showed that the use of LOPA provides the identification of a higher rigor in the classification of the appraised risks when PHA is used alone. The new analyses of risks should adopt LOPA for the verification of the quality of information generated with focus in the decision-making process for implementations of independent protection layers and in the operational safety's increase.