light products - Illuminating Engineering Society

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I I D A P R O J E C T
at the ends of the ceiling panels where the
dimension eventually approaches zero as the
wing panel touches the flat ceiling. The last
cove light fixture had to be separately dimmed
to make the appropriate transition. The main
trading floor incorporates two rows of concealed
asymmetric distribution fluorescent
cove lights mounted within the folded ceiling
panels. High output T5 lamps were used in
small optical assemblies.
Additional recessed ceramic metal halide
lamps were used to provide the direct lighting
component. The ceramic metal halide lamps
were used for their good color and reasonably
long lamp life. To complete the three-dimensional
modeling of the ceiling, semi-recessed wallmounted
compact fluorescent uplights were
used at the edges of the room. These fixtures illuminated
the underside of the ceiling panels. The
combination of these three lighting components
provided up to 45 footcandles, glare free.
A preset dimming system was designed to
control all of the trading area lighting systems,
maximize daylight harvesting and time-of-day
scheduling. The dimming system also controlled
all of the automated shade systems and the all of
the non-dimmed lighting loads throughout the
facility. The integrated control system allowed us
to easily commission the entire project in one
day and one evening. The system also benefits
users, allowing them full command from one
point of control, and provides significant energy
savings through time-of-day control, in addition
to the daylight harvesting.
Making Use of Daylight
The second challenge was to assess the effectiveness
of all of the fenestrations for what we
call “useable” daylighting. Traders have a reputation
for wanting to work in a dark room.
They’re jokingly called “vampires” because of
their sensitivity to light. This reputation comes
from years of exposure to bad lighting equipment
and designs used in conjunction with bad
monitors and trading turrets. Today’s monitors
are much more tolerant of ambient light than
those used five years ago. The lighting systems
do not have to be designed around reflections
in monitors any longer.
Extensive daylighting studies were performed
to evaluate the extent of useable daylight and to
develop a daylight control strategy for all of the
fenestrations. Each fenestration was assessed
for sky brightness and direct sun. A solar tracking
diagram was created to develop appropriate
shielding elements for each fenestration. The
shades on the north wall were angled 23 deg
from true north to accommodate the buildings
orientation. Each of the clerestories had individually
controlled shades. All of the shades were
designed to have 40 percent transmission to
Ceiling panels contain
indirect lighting and
recessed downlighting to
provide up to
45 footcandles, glare-free.
Traders have a reputation
for wanting to work in a
dark room. They’re jokingly
called ‘vampires’ because of
their sensitivity to light
reduce exposure. Blackout shades were considered
but deemed unnecessary.
This trading floor optimized the available daylight.
Automated shades were designed to track
the sun and to only allow diffuse daylight into
the room. The electric lights are either dimmed
or turned off when not required. The 50-ft tall
north wall of glass also had automated shades
to provide protection from excessive sky brightness,
which occurred early in the morning
throughout the year and at varying times during
the work day. During commissioning of the
lighting and shades, designers established a
time of day when the shades should rise, should
they be down because of sky brightness conditions.
When the 4:00 bell rang that signifies the
close of the markets, the shades would rise.
That great idea only lasted a few days. The
December 2005 LD+A 49