Acronyms & Terms Glossary

Risk Reduction Factor (RRF)

The Risk Reduction Factor (RRF) is the inverse of PFD (RRF = 1/PFD) and is used to establish the associated Safety Integrity Level (SIL) rating required for a Safety Instrumented Function (SIF) to reduce the hazard risk to an acceptable risk tolerance level. Once a Process Hazard Analysis (PHA) has been completed and Independent Protection Layers (IPL) have been applied, any SIF that serves as an IPL must have an established RRF.

Over-specification of devices to be used in a SIF is not uncommon because it is a SAFETY Instrumented Function. However, over-specification does not necessarily improve safety significantly and can reduce the resources available for overall safety. aeSolutions can help you identify the best devices to use in SIFs and assist you in the purchasing process.