Safety Integrity Levels (SIL)

Safety Integrity Levels (SIL) are measures used to specify how reliable a safety system is in preventing or mitigating dangerous events. They are classified from SIL 1 (lowest safety reliability) to SIL 4 (highest). Each level represents a required performance standard, including the likelihood that a safety function will work correctly when needed. Higher SIL levels demand more robust design, testing, and maintenance to ensure safety goals are consistently met. Essentially, SIL helps engineers design systems that effectively reduce risk to acceptable levels, ensuring safety in critical industries like oil & gas, chemicals, and manufacturing.