Operation Sound - Daikin VAM Series Engineering Data

Appendix

17.4 Operation Sound

A decision cannot be made simply on necessary airflow rate and static pressure. Acceptable noise is another factor that varies
according to the type of room being ventilated. Be sure to select by considering such factors as the type of room being ventilated and
the sensitivity of individuals in the room.
17.4.1 Decibel (dB) Unit for Operation Sound
The sound unit for operations is the decibel (dB). It expresses the noise level for the sound pressure level that is measured by the A
weighted sound of a sound-level meter. The measurement method uses the A weighted sound of a sound-level meter.
17.4.2 Level of Acceptable Noise
In architecture, the dB level for acceptable noise corresponds to each room type.
 Recommended Values for Stationary Noise in Rooms
Occupancy category
Concert halls
Broadcast studios
Large theaters, churches
Classrooms, libraries
Living spaces, reception rooms
17.4.3 Precautions for Noise Level
The noise values (dB) on product labels are measured by prescribed distances in a anechoic chamber as determined by JIS or other
standards. Please be aware concerning the following three items when employing these values.
(1) Sound Changing Environments
The measurement values were measured in an anechoic chamber. There are reverberations from walls, floors, ceilings, etc., in an
actual building, so please consider the reverberation coefficient of the room since values increase according to the material quality of
surroundings and size.
(2) Vibration Propagation
Products are designed and manufactured to keep vibration as low as possible, but because vibration occurs in a rotating body, please
keep in mind to install equipment tightly to the building and ensure that vibration propagation and sympathetic vibration do not occur.
(3) Sound Synthesis
Please be aware of sound synthesis when two or more units are installed in the same room.
176
Noise level (dB)
21 to 30 Bedrooms, hospitals, hotels
21 to 30 Small theaters, conference rooms
30 or less Factories, workshops
38 to 47 Lobbies, laboratories
38 to 47 Restaurants, large offices
(Source: Sound and Vibration Countermeasure Handbook (Japan))
Occupancy category
EDMMT712101
Noise level (dB)
34 to 47
42 or less
66 to 80
47 to 56
42 to 52
VAM-HVE/HVLT Series