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Combat Vandalism with Light Protective lighting is necessary for night time policing of outdoor areas to aid in reduction of vandalism and malicious damage, and to render the vandals visible to neighbors adjoining the park district property. Illumination for policing of a park area, however, is not usually adequate for efficient sports activities in the parks; therefore, protective lighting is generally treated as an auxiliary to other sports lighting in the parks. Two basic systems, or a combination of both, may be used to provide practical and effective protective lighting. The first method is to light the boundaries and approaches to the park areas; the second, to light the area and structures within the general boundaries of the parks property. In order to begin a project for lighting the Board should seek a competent engineer, reputable electrical contractor, or floodlighting manufacturer representative, or a combination of all three, that can provide a comprehensive protective lighting proposal. This proposal will provide the Board with an overall plan that includes the location of the equipment, the installation information, including distribution wiring, switching, etc., and the equipment itself. If the floodlighting is not engineered and designed properly, it will produce poor results and waste funds. The electrical contractor may then take these proposals and specifications and provide the Board with the installation costs and with the installation of the full protective lighting plan. The services of the floodlight manufacturer should include the basic lighting recommendation cost analysis to determine the advantages of one type of system over another, demonstrations, field assistance, etc. There are many other factors that arise with each individual job, but the above are the major considerations and approach to each job. Protective Lighting Equipment—In general, there are two broad forms of lighting equipment used in park illumination. These classifications are: 1. Floodlighting 2. Roadway Lighting Luminaires In addition, the above two categories of fixtures utilize the following sources of lamps to provide the proper distribution and solution to the lighting needs: Incandescent, Quartz-Iodine, Color-improved Mercury-vapor, Multi-vapor Metallic Additives, Lucalox. The choice of the type of equipment depends upon the pattern (distribution) of light, consideration of glare, convenience of servicing, maintenance, electric load, and mechanical construction. Floodlighting—A floodlight is a projector designed for lighting a scene or object to a brightness greater than its surroundings. It is usually capable of being pointed in any direction and is of weather-proof construction. This type of equipment is used to emphasize fine areas in parks (general area lighting) where it is desired to locate a lighting unit in an inaccessible area (to the vandal) and to project the lighting into the critical areas. Floodlighting may also be used for illumination of boundaries, fenced in areas, pools, buildings and for local emphasis of vital areas. Roadway Lighting Luminaires—Luminaires in this classification have various distributions of light from narrow to circular wide. A roadway fixture is a complete device consisting of the light source (lamp) together with a globe (refractor) reflector, housing and support mounting. This classification. Roadway Luminaires, is used mainly on roads, so we will confine our theme to primarily the floodlight unit and the lamp source it utilizes. The floodlight is a much more versatile tool with which to accomplish the lighting problems encountered in the parks areas for protective lighting as well as sports lighting. It follows now that before we get into a typical design utilizing the floodlight, we should discuss some of the terms used in discussing lamps and Illinois Parks and Recreation 12 March/April, 1974 fixtures. In order to better understand what can be accomplished with floodlighting, as in all industries, there are certain terms that are used to define the elements in that industry. IES—Illuminating Engineering Society — Organization of professional engineers, architects, fixture manufacturers. Set standards based on years of experimentation. Developments. The bible of reputable manufacturers. Lamp—The generic term for a man-made source of light. Lumens—All lamps are rated in lumens. This is the rated output of a light source, like horsepower, BTU, MPH, etc. Measurement of light intensity provided by the lamp source. Incandescent Filament Lamp—A lamp in which light is produced by a filament heated to incandescence by an electric current. Example: Lamp to home, Quartz-Iodine. Electric Discharge Lamp — A lamp in which light is produced by the passage of an electric current through a vapor or gas. Example: Mercury-Vapor, street light. Ballast — A device used with an electric discharge lamp to provide the necessary electrical condition for starting operating the lamp. Example: A ballast on a boat to stabilize the boat. Footcandle—Measurement of light intensity in an area provided by a particular floodlight and lamp source. Typical light sources available today for use in floodlighting:
Note from the above that for security lighting, which calls for the use of floodlighting all night long, every night of the year, the Color-Improved Mercury-Vapor is the most efficient with the longest life. A typical average usage of hours per night operation in a park is 10 to 20 hours, and based on 365 days a year, totals approximately 4000 hours that the floodlights will operate. Divide this into the 24,000-hour life of Color-Improved Mercury-Vapor and this means six (6) years' service from the Mercury lamp before it is to be replaced. At the same time, you will note that for the same wattage, the Mercury provides two-and-a-half times more light. This means for an equal level of illumination with Mercury-Vapor and incandescent your electric bill for the floodlighting will be two-and-a-half times less. Good lighting is efficient. Greater lighting economy results when the floodlighting is not wasted and maintenance is kept at a minimum. Old-fashioned incandescents are inefficient because the lamps need frequent replacing and light output (lumens) is low for the power consumed (electric bill). Efficient light sources (lamps) in properly designed floodlights effectively control the light to put it where it is needed, giving you more light for the money and attractive equipment that requires a minimum of maintenance. Illinois Parks and Recreation 13 March/April, 1974 |
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