GSA
Courtroom Lighting Criteria Evaluation
Task 1 Report
Tampa, Florida (Gibbons)
5.5
5.5.1
Lighting Scheme
The Gibbons courthouse in Tampa has a lighting scheme that illustrates the importance of
the design guidelines. It consists mainly of downlights in an architectural slot. They are
supplemented by recessed wallwashers and some tungsten halogen downlights at a
floating ceiling over the bench. A fluorescent cove light runs along the higher ceiling
section edge at the center of the room and provides indirect illumination to the underside
of the ceiling.
The downlights originally installed in the courtroom were a set of low CRI metal halide
downlights. These downlights cause significant problems because of their re-strike time
and a very significant ballast hum, which is loud enough to be disruptive to proceedings in
the courtroom. The metal halide downlights also provide poor color rendition. The use of
direct metal halide lighting is contrary to the Design Guides recommendations.
Several courtrooms in the Tampa courthouse have had the metal halide downlights
replaced with compact fluorescent (CFL) downlights of a similar type. Both types of
courtrooms were surveyed.
As the photos above illustrate, the two schemes arevr s ir tel i i s r ite
ey i l h u n r aen h
ma
m ae
same locations and provide similar light distributions. Despite providing acceptable light
levels, the metal halide scheme proved unworkable because of the issues relating to
ballast hum and restrike time. Additionally, the color rendering of metal halide lamps is not
sufficient for general illumination in courtrooms, as it is used in this case.
5.5.2
Lighting Control Scheme
The lighting control in this courtroom is provided by a scene-set dimming system. Pre-set
scenes are programmed into the control system, which can be selected by a controller at
the bench.
5.5.3
No access to daylight is provided in the courtroom.
Page 24
X:\...-05 REPORTS & NARRATIVES0124-TASK1REPORT-DRAFT3-
Ove Arup & Partners Consulting Engineers PC
8.5X11.DOC
Issue March 1, 2006
Previous Page
