Here is a sample Zoning Diagram below. See another sample diagram.
No sign shall be erected or maintained within the zone of light obstruction for any window opening into any habitable room of any residential unit. The "zone of light obstruction" is a segment of a cone described horizontally by an arc drawn from the centre line of the window, measured horizontally, extending to seventy (70°) degrees on either side of the centre line, at a radius of forty (40) feet and described vertically by the space between a plane extending horizontally from the window sill and a plane extending from the top of the window at an angle on one hundred and sixty (160°) degrees to the face of the building.
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