In our industry, major risks are associated with the processing of explosive, flammable or toxic substances. Identifying, assessing and managing risks associated with these substances are integral part of our continuous efforts to improve safety. The management of risks involves reducing the risks for both inside and outside our sites to a level As Low As Reasonably Practicable (ALARP). The principles involved in the assessment and management of major risks are: 1. Hazard identification 2. Preliminary risks evaluation 3. Detailed and quantified risks analysis 4. Risks assessment and ALARP demonstration 5. Development of a priority-based program of improvements and of a major risks register. There are two approaches for risks assessment, Aggregate Risk Assessment and Scenarios Based Risk Assessment. Although these methodologies are often complementary, the first approach allows calculating the aggregate risk to personnel, expressed as Individual and Societal Risk. Thus the a vantage of this approach is to address the global risk, the principal disadvantage is that it doesn’t allow identifying the main critical scenarios of accident and the final results (Individual and Societal Risks) are hidden in mathematical calculations, with the use of computer model. In the second approach, the Scenarios Based Risk Assessment, the critical events are selected in the preliminary evaluation step and studied in detail to establish the severity of damages and the likelihood of occurrence. The recommended methodology for the detailed risks analysis is the Bow-Tie approach (causes tree – consequences tree and safety barriers). Each critical scenario is assessed with respect to the Company risk acceptance criteria based on a Risk Ranking Matrix. This methodology ensures the demonstration of the ALARP level of the risks and the identification of the Safety Critical Measures (SCM). Definition and ranking of the additional risk-reducing measures allows preparing a priority based program of actions and a register of the Major risks.
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