Which item is not among the four main pre-design items for comprehensive commissioning?

• A. Establish commissioning
• B. Select a CxA
• C. Develop the commissioning scope
• D. Write Cx plan

Answer: (D)

The main idea here is distinguishing between setting up the commissioning process and actually planning how it will be carried out. Before design work begins, you establish the framework: you define who will lead the commissioning, choose the CxA, and decide what systems and functions will be in scope. These steps create the governance and boundaries that guide the entire commissioning effort.

Writing the Cx plan, while important, is a more operational step that documents how the commissioning will be executed—the schedule, tests, responsibilities, and deliverables. This plan typically comes after the initial scope and requirements are defined and the project team has aligned on expectations. It’s usually developed during design or early construction, not as a pre-design activity.

So the item not among the four main pre-design items is writing the Cx plan.