In a CCTV system layout, what does "AFF" stand for when a camera is mounted at 12'?

In the context of a CCTV system layout, "AFF" stands for "Above Finished Floor." This term indicates that the measurement referenced, in this case, the camera height of 12 feet, is taken from the finished floor surface up to the bottom of the camera or the mounting point. It is important in various construction and installation practices to specify measurements relative to a consistent reference point, which is the finished floor, as it accounts for things like flooring material thickness and any changes in elevation. Using "Above Finished Floor" helps ensure that installers can position cameras at the intended height for optimal coverage and functionality according to the design plans.

The other terms, while they may seem similar, are not standard references used in this type of measurement for security systems and do not convey the precision needed in CCTV installation practices. "Above normal floor" and "At normal floor" lack the specific reference to the finished nature of the surface, which is critical for accurate installation and assessment. Meanwhile, "At finished floor" suggests a level at the floor surface itself rather than above it. This distinction is crucial for achieving desired surveillance heights and angles in a CCTV system.