No lights, vibrations, noise, glare, radiation's, dust, odors or smoke shall be propagated, generated or permitted to occur on any lot in Business B districts except so that no effect of any of them shall be visible, audible or perceptible beyond the boundaries of the subject lot. Nevertheless, Business B premises and parking lots may be wholly or partly floodlighted provided no lighting filament, lamp, bulb or tube is directly visible from any point outside the lot boundary of premises so illuminated.