Figure 6-10. - Ribbon splice on etched silicon chip.

AREA LIGHTING SYSTEMS

Streetlighting at naval facilities usually need not produce as high a level of illumination as that required in many municipal areas. Because night activity by vehicles and pedestrians is low, only enough light is supplied to permit personnel to identify streets and buildings and to furnish sufficient visibility for local security requirements. Requirements for security and floodlighting systems will depend on the situation and the areas to be protected or illuminated.

STREET AND AREA CLASSIFICATION

Streetlighting requirements generally consist of a minimum average maintained footcandle level and a maximum allowable uniformity ratio for the instal- lation. The authority for these requirements is the American National Standards Institute (ANSI)/Illuminating Engineering Society (IES) publication, Standard Practice for Roadway Lighting. Another publication that may prove helpful is Informational Guide for Roadway Lighting, published by the American Association of State Highway and Transportation Officials. The only significant dif- ference between the two publications is that the latter allows a 4 to 1 uniformity ratio instead of the 3 to 1 uniformity ratio specified by IES. These uniformity ratios are defined as the ratio of the average footcandle value divided by the minimum footcandle value.

LIGHTING INTENSITY

The illumination and uniformity requirements are given in table 6-1. Note that the illumination level is dependent upon the roadway classification and the area classification that are defined in the following material.

Streets are classified into three major categories: major, collector, and local.

Major: The part of the roadway system that serves as the principal network for through traffic flow. The routes connect areas of principal traffic generation and important rural highways entering the city.

Collector: Distributor and collector roadways serving traffic between major and local roadways. These are roadways used mainly for traffic movements within residential, commercial, and industrial areas

Local: Roadways used primarily for direct access to residential, commercial, industrial, or other abutting property. They do not include roadways carrying through traffic.

The locality or area is also defined by three major categories: commercial, intermediate, and residential.

Commercial: That portion of a municipality in a business development where ordinarily there are large numbers of pedestrians and a heavy demand for parking space during periods of peak traffic or a sustained high 6-9