Polycom 2457-26122-001 User Manual

Page of 280
 Integrator’s Reference Manual for the Polycom RealPresence Group Series
238
Polycom, Inc.
 
Ceiling Tiles
These should be high-quality acoustic tiles, ideally 1”- thick compressed 
densecore fiberglass. An added benefit of this kind of ceiling tile is that it 
works well with the indirect lighting as specified elsewhere in this section. To 
reduce any extraneous noise from leaving or entering the room via the ceiling 
space, the ceiling tiles can be blanketed completely from the plenum side, with 
a minimum of 6”- thick unfaced dense fiberglass batting or mineral rock wool, 
(the equivalent of R-15 to R-19). Here again, a barrier layer will improve the 
performance, but all local building codes must be followed for allowable 
materials in the various aspects of room acoustic modifications. To make entry 
and exit from the ceiling space easier, the blanket and barrier do not need to 
rest on the ceiling tiles, but may be suspended above it.
Air Conditioning
It is critical that all air-handling equipment (blowers, heat exchangers, 
solenoid valves, etc.) be located outside the physical meeting room space. This 
will prevent the noise burden associated with such equipment from affecting 
the participants of any meetings held in the room. Location of air-handling 
equipment within the ceiling space of a conference room often renders that 
room unusable for video or audio-only conferencing.
The air vents should be of open construction to eliminate “wind noise” while 
the system is running. These vents normally are specified as “low-velocity” 
diffusers. The number of air vents within the room should be sufficient to 
maintain a consistent temperature throughout the space. All HVAC ducts and 
diffusers should be oversized for the general application in the space, with 
minimum 2’ diameter insulated flexible ducts and matching 2’ noise 
dampening diffusers generally best. All ducts should be installed with gradual 
bends and curves rather than rigid 90-degree corners. This will minimize 
“thunder” sounds as the initial air pushes through the ductwork and into the 
room.
There should be a thermostat to control this specific room system 
independently of the rest of the building, and that control should be located 
within the room.
Important: Allow an additional 5,000 BTU of cooling capacity for a standard 
“roll-about” singlemonitor VC system with extended in-room peripherals 
(PC, document camera, scan converter, etc.) and a minimum of 10,000 BTU for 
a dual display multimedia presentation system with large screen displays. For 
the comfort of the participants, the room must accommodate these heat loads, 
plus the heat load of a room full of people, with minimal temperature rise.