period four
Equipment Sound Rating
notes
Reverberant-Room Method
Figure 60
The most common test method for HVAC equipment is the reverberant-room method. The objective of a reverberant room is to create a uniform, or diffuse, sound field by reflecting and mixing the sound waves. The walls, floor, and ceiling of the reverberant room are hard, in order to cause multiple reflections of sound waves. In this environment, the sound pressure is essentially the same at all locations within the room.
Sound-pressure levels are measured in the reverberant room and used to calculate sound-power levels for the piece of equipment. The reverberant-room method is commonly used to determine the sound power of fans, air handlers, compressors, in-room air conditioners, terminal equipment (such as fan-coils and VAV boxes), and diffusers.
