Surface lighting is used to display a silhouette of any person passing between the light source and the building or to show the contrast of a person inside the building.

• A. True
• B. False
• C. Not Applicable
• D. Sometimes

Answer: (A)

Surface lighting relies on a bright light on the exterior surface and a darker area in front of it, so when someone passes between the light and the wall, their body blocks the light and appears as a clear silhouette on the facade. This backlit silhouette is easy to detect and helps security personnel and cameras notice movement. The same principle can apply with interior activity: if interior lighting creates a contrast against the outside, a person inside can show up as a distinct shape or shadow through the window, making their presence noticeable. In short, backlighting to create silhouettes and contrast is exactly how surface lighting functions in this context.