We at Samarth safety offer, Layers of Protection Analysis (LOPA), which is another risk assessment technique, more commonly used to determine the required Safety Integrity Level (SIL) for Safety Instrumented Systems (SIS) under specific standards.

With the use of this, we aim at minimizing causalities. This methodology essentially differentiates between installed risk reduction measures. The outcome from most risk assessment techniques records all the risk reduction measures. These measures can include items of plant and equipment, human actions and procedures, etc.

LOPA defines certain measures as special and calls them Independent Protection Layers (IPLs).

IPLs are the defined measures in which it is:

  • Independent – they act on their own
  • Effective – they will prevent the hazardous scenario (if they work)
  • Auditable – are capable of being formally tested

All the identified risk reduction measures are screened, and non-IPLs are removed before deciding if the remaining IPLs reduce the level of risk to an acceptable Target Risk Level or not. The story of risk reduction achieved or credit for each identified IPL is determined using a LOPA Rule Book (which specifies how risk reduction credits can be awarded for various situations).

We are actively involved in helping operators to determine whether or not proposed, and existing safety-related systems can provide the necessary level of risk reduction or SIL, consistent with the requirements of the standards.

We can help you with :

  • Specify appropriate IPLs
  • Identify Safety Instrumented Functions (SIF)
  • Determine appropriate target SILs for SIS
  • Validate proposed or existing designs for SISs to ensure the SILs can be achieved
  • Prepare essential documentation for on-going inspection, functional testing, and maintenance of SISs
  • Safety Barrier Identification
  • Safety Objective Analysis (SOA)
  • Probability of Failure on Demand Determination
  • Layers of Protection Analysis
  • Safety Integrity Level (SIL) Determination
  • Risk Acceptance Criteria
  • Risk Judgment Techniques
  • Special Application of LOPA for an Independent Protection Layer