4. How high should I mount and where?
There are two common issues when floodlighting outdoor industrial complexes: the multiplicity of shadows caused by the nature of the site, and the fact that the visual tasks occur on planes other than the horizontal.
Quick tip: design for an appropriate horizontal illuminance at ground level, assuming there are no obstruction losses. Information about the actual obstructions, whether temporary or permanent, will be required to resolve the mounting height and location of floodlighting positions to minimise shadows.
Columns at a height of 6-20m would appear to be the most obvious answer but look at your space and its use. Do you need general and localised lighting? Do people and vehicles both operate in the same space? Could column mounted luminaires be obstructive – if so consider wall mounting.
Quick tip: This is a real balancing act. If you are looking for uniformity then the higher the mounting height, the smaller the number of columns required. But, this is not true when considering average illuminance where the higher the columns the greater the loss of intensity (via the inverse square law), so you may need more output from the luminaire. The relationship between mounting height and the depth of the area to be lit is therefore important.