Safety Instrumented System Safety Lifecycle

What Does Safety Instrumented System Safety Lifecycle Mean?

A safety instrumented system (SIS) refers to a critical system that consists of one or more automatic safety instrumented functions (SIFs). The SIS safety lifecycle encompasses all phases of the system’s life including design, research, development, test and evaluation, production, deployment (inventory), operations and support, and disposal.

Safeopedia Explains Safety Instrumented System Safety Lifecycle

The IEC 61511, a technical standard for SIS for the process industry sector, defines a safety lifecycle as “necessary activities involved in the implementation of SIFs occurring during a period of time that starts at the concept phase of a project and finishes when all of the safety instrumented functions are no longer available for use”.

The lifecycle approach, as described in various technical standards, utilizes common sense, is a closed loop process, and is continuous.

The safety lifecycle model is similar to the Plan-Do-Check-Act cycle, but is divided into the following three phases:

• Analysis Phase - the problem is identified and assessed
• Realization Phase – the problem is solved and verified
• Operational Phase – the solution is put into use