A county correctional complex had been enduring high noise levels in their
first floor office area for approximately 10 years when they contacted
Unger Technologies. The noise was emanating from a basement mechanical
room located directly below the offices. After continuous complaints
from administrative staff and officers, management decided to address
the noise problem and called Unger Technologies.
Unger Technologies recorded 1/3 octave band sound level readings in the
basement mechanical room (98 – 100 dBA) and the first floor offices (70
– 75 dBA). It was determined that the primary noise generator was a
large Liquid Cooled Chiller which exceeded 100 dBA above the unit. The
noise levels in the basement mechanical room exceeded OSHA limits for
worker safety and engineering controls were recommended for the Chiller
Unit.
Unger Technologies designed and installed a sound curtain enclosure. The
four sided enclosure with roof was constructed of tubular steel uprights
and base plates supporting a rigid panel roof and a double track hook
and trolley panel suspension system. The sound curtain panels were a
1lb. per square foot loaded vinyl sound barrier bonded to a 2” thick
acoustical absorber with a vinyl facing. The panels are suspended from a
double track with hook and trolleys where as every other panel rides on
a separate track so the panels will slide behind each other providing
accessibility for maintenance. Four silenced ventilation panels coupled
with roof mounted fans provided cooling air for the equipment. Four 1
lb. per square foot clear vinyl window were strategically positioned
within the curtain panels to allow viewing of the gages without opening
the enclosure.
The customers noise reduction goals were exceeded in the basement
mechanical room (18-20 dBA reduction) and the first floor offices (20 –
24 dBA reduction). The staff was pleased with the quieter work
environment and management enjoyed a happier safer workplace.
