A NEW METHODOLOGY FOR MAJOR ACCIDENT HAZARD RISK ASSESSMENT ACCORDING TO EU DIRECTIVE ON OFFSHORE SAFETY

摘要

Eni has developed an innovative methodology for assessing major accident risks relating to offshore oil and gas operations in order to demonstrate that the risk level for people and the environment is tolerable, in compliance with the European Directive 2013/30/UE and the corresponding Italian Decree 145/2015. The risk assessment process is based on the bow-tie methodology that is applied in a 'quantitative' way to determine the frequency of the most significant risk scenarios, identified in a preliminary HAZard Identification session. The frequency calculation takes into account the efficacy of all safeguards in place for preventing the top event occurrence or mitigating the incident effects considering a set of human and operational control and equipment reliability factors, derived from SPAR-H methodology, that characterise the effectiveness and integrity of each barrier. The risk methodology has been extensively applied to the Eni upstream offshore installations in Italy although it is standardisable for a possible extension worldwide. Since the risk methodology is operations-oriented, it has been proven suitable for the identification of SECEs and for defining their performance standards and therefore driving safety improvements and ensuring legislation compliance at the same time. The methodology has been benchmarked with the approaches used by other Member States, particularly in the North Sea and constitutes a valid approach for the entire Mediterranean Basin, as recognized by the Authorities after numerous meetings and workshops hosted by the interested parties. In Italy, the methodology has been included into the Guidelines expressely issued by the Competent Authority.