22 August 2006
Fully shielded or full cut-off
luminaires control glare
and reduce light pollution
Spacing of luminaires
provides uniform horizontal
illuminance in parking
Pole mounted metal halide,
Metal halide, induction, or
Control with photocell,
high-pressure sodium lamp.
timeclock, or motion sensor
CRITICAL DESIGN ISSUES:
Direct Glare: Because the surroundings may be very dark at night,
consider direct glare from luminaires and excessive contrast of surfaces.
Luminaires should use shielded lamps and as low a wattage as possible.
Light Pollution / Trespass: The use of fully shielded or IESNA full-cutoff
luminaires eliminates direct light above the horizontal plane. Using cut-off
optics and low wattage lamps can minimize light pollution. Shielded
luminaires minimize the chance of light trespass on a neighboring property
Modeling of Faces or Objects: By providing light from multiple directions,
objects and people are accurately rendered and modeled.
Peripheral Detection: Our sense of security 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) allows faster peripheral detection than the
"fuzzy" high-pressure sodium light sources. Also, colors are rendered
more accurately under white light.
Reflected Glare: Wet surfaces often provide a surface that has the
potential for reflected glare. Select and locate luminaires to minimize this
as much as possible.