The objective of this research is to Safety Integrity Level (SIL) using Layer of
Protection Analysis (LOPA) for Compressor 013K101A. The advantage using this
method is identifying hazard and providing evaluation Independent Protection Layer
(IPL) management for compressor unit refinery IV Cilacap, PT.Pertamina Persero.
HAZOP of compressor is used for identify hazard in Compressor process. Identify every
IPL which prevent hazard at compressor. Determine target mitigated event likelihood
(TMEL) and initiating event likelihood (IEL). The comparison of TMEL and IEL will
determine target SIL. The result from SIL evaluation using will determine SIL for SIS
which used for recommendation for hazard at compressor process. SIS
Recommendation is done with calculates Probability failure demand (PFD)SIS with
various combinations of sensors and emergency shutdown valves (ESDV) configuration.
Recommendation is the combinations which SIL target which identifies 3 hazards level.
Case 1 needs SIL 2 with PFD value 0.0063. Case 2 got no SIL with PFD value 0.3600;
therefore SIS isnít needed for condition. Case 3 got no SIL with PFD value 3.6000.
Therefore SIS isnít needed for Case 3. SIS recommendation for case is PLC logic will
trip emergency shutdown valve with 1oo1 configuration at high 013V104 level using a
high level switch LSH. This SIS can fulfill the requirement of target SIL 2 with PFD