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Back Rotary Splices | Up Construction Electrician Intermediate - Electricity handbook for electricians | Next Selection of Luminaries |
Figure 6-10.Ribbon splice on etched silicon chip.
AREA LIGHTING SYSTEMS
LIGHTING INTENSITY
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.
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.
STREET AND AREA CLASSIFICATION
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.
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
A m e r i c a n N a t i o n a l S t a n d a r d s I n s t i t u t e
(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.
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
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