Safety Integrity Level (SIL) is a key concept in functional safety used to specify the required level of risk reduction associated with a safety function. In process industries, SIL is closely associated with Safety Instrumented Functions (SIFs) implemented through Safety Instrumented Systems (SISs). SIL is often misunderstood as a rating…
Layer of Protection Analysis (LOPA) is a structured process safety method used to evaluate whether existing safeguards provide enough protection against a hazardous scenario. In a typical process plant, a single hazard may have several safeguards around it. These can include basic process controls, alarms, operator actions, shutdown systems, relief…



