The safety integrity level, or SIL for short, is an indicator that makes risk reduction quantifiable. Plant and machinery can pose risks that are so dangerous that people and the environment should not be exposed to them under any circumstances. If such a hazard exists, the associated risks must be mitigated to meet the need for safety.
SIL is a core element of functional safety and simultaneously the object of many misconceptions. Pepperl+Fuchs clarifies three of the most common misunderstandings.