Which combination correctly lists the three plant boundaries?

• A. Public Area, Security Area, and Critical Area.
• B. Restricted Area, Public Area, and Controlled Area.
• C. Owner Controlled Area, Protected Area, and Vital Area.
• D. Facility Exterior, Plant Interior, and Reactor Area.

Answer: (C)

The main idea is that plant access is organized into three nested boundaries, each deeper layer representing tighter protection and stricter access rules. The outermost boundary is the Owner Controlled Area, where the facility governs general access and visitor screening. Inside that, the Protected Area holds safety-related systems and components and requires more controlled entry. At the innermost ring lies the Vital Area, the most sensitive zone with the highest level of restriction and authorization required to enter. This progression ensures that as you approach the most critical assets, credentials, escorts, and procedures become more stringent. The other options mix areas that don’t form this standard three-layer boundary model used in this training, so they don’t represent the correct set of plant boundaries.