Which activity is a direct responsibility of Trade Contractors during commissioning?

• A. Providing input into commissioning plan for CxA's review and approval
• B. Executing and documenting tasks in construction checklist and start-up process
• C. Update design narratives in the BOD
• D. Review the commissioning plan

Answer: (B)

During commissioning, trade contractors are the on-site implementers who actually perform the installation, start-up, and testing activities and record the results. Executing and documenting tasks in the construction checklist and the start-up process is their direct responsibility because these documents capture the concrete work completed, the tests run, and the evidence of proper sequencing and operation. This on-site evidence is what the commissioning team uses to verify readiness and progress toward acceptance.

Other activities involve the planning and design teams or the commissioning authority. Providing input into the commissioning plan, updating design narratives in the Basis of Design, and reviewing the commissioning plan are typically done by the CxA, design professionals, and project management rather than by the trade contractors.