(56b) Is the Cost of Implementing the IEC 61511 Safety Lifecycle Justifiable?

So you’ve conducted Process Hazards Analysis’s (PHAs) / Layer of Protection Analysis’s (LOPAs), completed Safety Integrity Level (SIL) Calculations, Safety Requirements Specifications (SRS), and Functional Test Plans at your facilities. Is this cost justified? Before this question can be answered let’s explore what “follow the IEC 61511 safety lifecycle” requires. Simplistically, the safety lifecycle embodies a three-step methodology to overall risk management, which can be summarized as follows:

1. Execute safety lifecycle documentation (PHA / LOPA, SIL Calc, SRS, Test Plans, etc.)

2. Monitor protection layer performance

3. Sustain safe unit operations through corrective actions

The true value of the safety lifecycle lies in the Monitor and Sustain steps noted above. However, most companies are not monitoring the performance of protection layers, and therefore are not using the safety lifecycle as a mechanism to sustain and optimize the business. As such most end users are completely unaware of their actual risk profile versus the initial assumed risk profile completed in the execute step of the safety lifecycle. This paper explores the financial risks associated with not verifying assumptions made during the execute step of the lifecycle over the life of the facility and provides one the means to justify the cost of implementing the safety lifecycle.