What does the 'safety critical' concept refer to in LOPA?

The concept of 'safety critical' in Layer of Protection Analysis (LOPA) specifically refers to systems that are essential for preventing hazards. In the context of LOPA, safety critical systems are those whose failure could lead to significant consequences, including injuries, environmental damage, or loss of life. These systems must operate correctly to ensure that the inherent risks associated with processes are sufficiently mitigated.

In LOPA, a thorough evaluation of these safety critical systems is crucial because they often serve as the final layers of protection that intervene in the event of a hazardous scenario, thereby reducing the likelihood or severity of an incident. This focus on correct functionality is why identifying and assessing safety critical systems is a vital part of risk management efforts in industrial environments.