Sound Attenuation By A Noise Barrier - Sanyo SGP-EW120M2G2W Technical Data Manual

System Design

(3) Sound attenuation by a noise barrier

Sound attenuation of an indoor unit at a reception point behind a noise barrier or building depends on the
frequency and path length difference.
δ = path length difference
δ = (A+B)－d
Ex. 1
Outdoor unit
Ex. 3
Outdoor unit
● The barrier should be located as close as possible to the outdoor unit (sound source). (Figure 3)
(Be certain to preserve the required space for air intake and exhaust, service and maintenance.)
● The barrier should be sufficiently higher than the top of the outdoor unit. (Figure 3)
(However, not more than 1m higher.)
● The width of the barrier should be at least several times the height, on both sides of the center. Where this is
not possible, the barrier should bend around the unit as shown in Figure 4.
Outdoor unit
As close as possible (while maintaining minimum clearances
required for intake, exhaust and servicing of each unit)
Figure 3. Sound barrier
A
B
●
Reception point
d
A
B
●
d
Reception point
建
物
Effective area
A
1 m or less
B
6. Sound-proofing measures
Ex. 2
Outdoor unit
Figure 2. Diffraction attenuation
At least several
times the barrier
height
●
Reception point
At least several
times the barrier
height
D-27
A
d
B
Building
●
Reception point
Outdoor unit
When adjoining
barriers, longer
than this line.
Figure 4. Sound barrier