SIL Study
Safety Integrity Level determination and LOPA for Safety Instrumented Systems to IEC 61511.
Request This ServiceWhat is a SIL Study?
A Safety Integrity Level (SIL) study establishes the required performance level — SIL 1, 2, 3, or 4 — for each Safety Instrumented Function (SIF) within a Safety Instrumented System (SIS). The higher the SIL, the more reliable the safety function must be.
SIL determination is governed by IEC 61511 (for process industries) and IEC 61508 (for functional safety of electrical, electronic, and programmable safety systems). The primary method used is Layer of Protection Analysis (LOPA), which provides a semi-quantitative risk assessment of each hazardous scenario.
Raizon conducts SIL studies from initial hazard identification through to final SIL verification, producing documentation that satisfies both regulatory requirements and engineering design needs.
What We Deliver
- SIL determination report (IEC 61511 compliant)
- LOPA worksheets for each hazardous scenario
- SIL classification register for all Safety Instrumented Functions
- Basis of safety documentation
- SIS design requirements specification
Standards Referenced
IEC 61508, IEC 61511, ISA 84, OSHA 29 CFR 1910.119
Who Needs a SIL Study?
Any plant that has automated safety systems — Emergency Shutdown (ESD), Fire & Gas (F&G), or Burner Management Systems (BMS) — requires SIL determination to demonstrate that each safety function achieves the required risk reduction.
Our Approach
Hazard Identification
Review existing HAZOP or HAZID documentation to identify Safety Instrumented Functions requiring SIL classification.
Risk Assessment
Apply LOPA or risk graph methodology to determine required SIL for each SIF based on consequence severity and initiating event frequency.
SIL Verification
Calculate achieved SIL based on proposed SIS design (sensors, logic solver, final elements) and verify compliance with target SIL.
Documentation
Issue SIL determination report, classification register, and basis of safety documentation in line with IEC 61511.
Ready to start your SIL Study?
Contact Raizon today for a free consultation. We'll discuss your requirements and provide a tailored proposal.