Objective 

To provide basic concept and methodology of LOPA and the detailed stages of its application. 

Overview 

Layer of protection analysis (LOPA) is a semi-quantitative tool for analyzing and assessing risk on a process plant. This technique can be used for As Low As Reasonably Practicable (ALARP) demonstration of risks arising from Major Accident Events (MAEs) and High Risk hazards. It uses an order of magnitude technique to evaluate the adequacy of existing or proposed layers of protection against known hazards. Details on the LOPA methodology can be found in “Layer of Protection Analysis (LOPA) Guideline”, Doc. No. 12004-GDL-SSHE-415-004-R00.