CSI defines commissioning as a quality-focused process that verifies the facility and its systems meet the Owner’s Project Requirements (OPR). In the Project Delivery Practice Guide, commissioning is categorized into three broad types (paraphrased):
Systems and equipment commissioning – verifying that HVAC, electrical, plumbing, life safety, and other building systems perform as intended.
Building envelope commissioning – verifying performance of the exterior enclosure, including air/water infiltration, thermal performance, and durability.
Total project commissioning (also called whole-building or total building commissioning) – extending commissioning to the entire project, including design, construction, and operational aspects, integrating envelope, systems, and other building components.
Given that the question already lists “systems and equipment commissioning” and “building envelope commissioning,” the missing third category described by CSI is “total project commissioning”, which corresponds to Option D.
Why the other options are not correct:
A. Mechanical commissioning – This is a subset of systems and equipment commissioning (focused on HVAC/mechanical systems), not one of CSI’s three overarching categories.
B. Facility commissioning – While the term might be used informally, CSI’s categorized terminology in the CDT body of knowledge is “total project commissioning” rather than “facility commissioning.”
C. Process commissioning – This term is more common in industrial process industries and is not identified by CSI as one of the three principal commissioning categories for building projects.
CSI References (no links):
CSI Project Delivery Practice Guide – sections on commissioning types and scope (total project, systems and equipment, building envelope).
