Answer:
7ft (2.13 m).
Explanation:
From the question above, the following parameters/data are given; the room dimension = 12 ft × 18 ft (∼3.7 m × ∼5.5 m), the floor-to-ceiling height = 9 ft (2.8 m) and the spacing ratio for the luminaire is 1:0.
Note that, we are not given the value or data for the height of the plane, therefore, we will make an assumption that the height of the plane = 2ft.
Hence, the work plane to luminaire distance = (9 - 2)ft = 7ft (2.13 m).
So, the maximum distance that the luminaires can be separated and achieve uniform illuminance is;
= the work plane to luminaire distance × spacing ratio for the luminaire.
= 7ft (2.13 m) × 1 = 7ft (2.13 m).
Thus, the maximum distance that the luminaires can be separated and achieve uniform illuminance is 7ft (2.13 m).