Who is responsible for blocking valves that isolate a reboiler before work is begun?

• A. Maintenance
• B. Engineering
• C. Operations
• D. Supervisors

Answer: (C)

Isolating energy and ensuring the work area is safe to begin maintenance is controlled by the operations team. They manage the plant’s process control and energy shutdown procedures, including blocking valves and applying lockouts so the reboiler cannot be energized or fed with steam while work is underway. This ensures a verifiable, safe condition before any maintenance begins. Maintenance may perform the actual work, but the authority and responsibility for the isolation and lockout typically rest with operations to coordinate, verify that all energy sources are isolated, and authorize the permit to work. Engineering provides the system design and procedures, but does not carry out the field isolation. Supervisors may oversee the process, but the hands-on isolation and lockout control come from operations.