Parking lots which are operated and open to use during the hours of darkness after one hour after sunset shall be provided with lights and lighting facilities that will provide 0.03 watt per square foot with incandescent light source, or 0.01 watt per square foot with either mercury vapor or fluorescent light source, but in no event less than 0.2 foot-candle average maintained illumination on the entire parking lot surface and an average ratio of six to one (6:1). (Prior code § 28-1-7)