Re: industrail recepticle
You would normally put it where the user wants to have it.
If it's a counter top, then put it above the counter so that the cords don't have to extend across the counter and down to the floor. If it's a free standing desk, then put it down at 18" so that the cords on the desk can drop down over the edge of the desk. This keeps the desk looking cleaner. Also consider using a double-duplex at a desk. There are way too many plug strips being used throughout a commercial office.