Zennir Youcef2024-05-202024-05-202020-12-082543-3792http://dspace.univ-skikda.dz:4000/handle/123456789/1757In order to maintain the integrity of its installation, the BIR EL MSANA (BMS) oil company has equipped itself with a safety instrumented system (SIS), complying with IEC 61508 and IEC 61511 standards. Whereas some constitutive functions of this system are disabled and not available, this means that the installations remains unprotected for a significant period of time, hence the obligation to look for adequate and permanent solutions. Through this work, we clarify the causes that led to this deactivation, proposing effective solutions for each case, this will allow reactivating them and ensuring a safe and sustainable exploitation.enImprovements in the performance of an SIS by bypass reduction on the safety functionsArticle