A Case of Complexity Versus Simplicity

At the first decision point we encounter in performing effective PSSRs, we evaluate the overall risk presented by  

This risk-based ranking is fairly straightforward. Risk will be assessed for the activities associated with the trigger event or installing the change, introducing chemicals to the changed equipment, the startup period, as well as the equipment s operation after startup. 

It is impossible, and essentially unwarranted in many cases, for facility management to resolve all process change issues simultaneously and at the highest level of detailed attention. Practicality and pragmatism tell us that some items are 

The following example of a basic priority risk-ranking matrix system is provided to display one tool for determining whether the change or trigger event is simple - and able to use a short form PSSR - or more complex, thus in need of a long form PSSR. 

The term simple should not be misunderstood as we use it in this book. It does not mean this category of PSSR is less important than a complex PSSR. It is intended to indicate the level of effort needed is well understood and fairly straightforward. Whenever we use the terms simple PSSR or short-form PSSR, they indicate a less resource-intensive approach to verifying readiness for startup when the trigger event has a lower level of risk. 

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