22 August 2006
VEHICLE TRAFFIC AREAS
Roadways and Streets
Fully shielded or full cut-off
luminaires control glare
and reduce light pollution
Spacing luminaires 4-5
times the mounting height
provides uniform horizontal
Pole mounted, fully shielded or full
cut-off roadway luminaire.
high-pressure sodium lamp.
CRITICAL DESIGN ISSUES:
Appearance of Space and Luminaires: Paint luminaires and poles a
neutral color so that they are as inconspicuous as possible.
Direct Glare: Fully shielded or full cut-off luminaires conceal the light
source and minimize the direct glare from the luminaire. Because the eye
adjusts to the brightest source in the field of view, eliminating glare is the
highest priority in designing for nighttime driving.
Light Distribution on Surfaces: More important than light level, uniform
light distribution provides high visibility and a comfortable nighttime driving
Light Pollution / Trespass: Fully shielded or full cut-off luminaires prevent
any direct light from leaving the luminaire above horizontal. This direct
light is the largest contributor to light pollution and light trespass.
Peripheral Detection: Detecting hazards while driving relies heavily on
peripheral vision. Research shows that peripheral vision and detection
are enhanced under white light. White light (as opposed to more orange
light produced by high-pressure sodium) renders objects sharper and