Construction commissioning begins during which phase?

• A. Pre-design
• B. Construction
• C. Design
• D. Acceptance

Answer: (B)

Commissioning work aimed at verifying that installed systems perform as intended cannot happen until the equipment and controls are actually in place. That makes the Construction phase the starting point for construction commissioning, because this is when systems are installed, wired, and accessible for functional testing, sequence checks, and integration. The design phase sets up the basis of design and the commissioning plan, but the hands-on verification and performance testing occur once construction is underway. Acceptance and occupancy follow after testing confirms performance, but the initial commissioning activities begin during construction as installations become testable.