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29 <br />Staff is attempting to develop a calculation to identify a limit on the total cumulative <br />amount of light generated on a parcel of property prior to the lights ever being erected. <br />By establishing a lumen limit we are, in effect, regulating the total amount of visible light <br />that can be generated on a given parcel of property. <br />Think of it this way: the foot-candle measurement provides us with the output of a light at <br />a given point while a lumen measures the results of that light's output in total. Staff <br />believes that we need both tools in our arsenal to properly regulate lighting and avoid <br />ancillary impacts on adjacent property owners. <br />Why not use the wattage of a light source as the `cap'? <br />Different bulbs produce different intensities of light at similar `watt' ratings. For example, <br />a 50 watt metal halide bulb will generate approximately 1,900 lumens while a 50 watt <br />high pressure sodium bulb will generate approximately 3,600. A helpful table outlining <br />various bulb wattages and output intensities is as follows: <br />source: Dark Sky International <br />The wattage of a bulb does not equate to the overall intensity of the light and cannot be <br />used to establish how much light should be generated on a given parcel of property. <br />