Which sequence best describes zones from outermost to innermost?

Which sequence best describes zones from outermost to innermost?

• A. Outer Perimeter, Sterile Area, SIDA
• B. Sterile Area, SIDA, Outer Perimeter
• C. SIDA, Outer Perimeter, Sterile Area
• D. Outer Perimeter, Sterile Area, SIDA

Answer: (D)

Access to airport security zones is layered, moving from public space to more restricted areas. The outermost boundary is the Outer Perimeter, guarding against unauthorized entry from the outside. Inside that boundary lies the Sterile Area, the secured space you reach after screening where access is controlled. Within the Sterile Area is the SIDA—the Security Identification Display Area—which is the most restricted portion and requires a valid badge to enter. So the sequence from outermost to innermost is Outer Perimeter, Sterile Area, SIDA. Placing either Sterile Area or SIDA before the Outer Perimeter would ignore the actual order you must pass through to reach restricted spaces, and placing SIDA outside the Sterile Area would misrepresent where badge-controlled access is required.

Access to airport security zones is layered, moving from public space to more restricted areas. The outermost boundary is the Outer Perimeter, guarding against unauthorized entry from the outside. Inside that boundary lies the Sterile Area, the secured space you reach after screening where access is controlled. Within the Sterile Area is the SIDA—the Security Identification Display Area—which is the most restricted portion and requires a valid badge to enter.

So the sequence from outermost to innermost is Outer Perimeter, Sterile Area, SIDA. Placing either Sterile Area or SIDA before the Outer Perimeter would ignore the actual order you must pass through to reach restricted spaces, and placing SIDA outside the Sterile Area would misrepresent where badge-controlled access is required.