Sound-Proofing Measure; Installation Location And Sound-Proofing Measures; Attenuation Of Sound Through Dstance - Sanyo SGP-E70J2GU2 User Manual

Design

(1) Installation location and sound-proofing measures

● When there is no suitable installation location, and it is necessary to install in a narrow location, where there
are other houses, offices or buildings nearby, it is necessary to provide walls, sound absorption chambers or
other secondary sound-proofing measures.
● Secondary sound-proofing measures include
• Attenuation through distance
• Sound-proofing with a noise barrier
• Sound-proofing using a sound absorbing chamber
• Sound-proofing by vibration isolation (anti-vibration pad, flexible couplings, etc.)
The following criteria are from Tokyo Pollution Prevention Regulations.
Criteria for every day sound levels (from Tokyo Pollution Prevention Regulations)
Condition
Area type
Type Housing
1 school area, etc.
Type Housing
2 undesignated area
Commercial,
Type industrial,
3 industrial areas,
etc.
Shopping
Type
specially designated
4
area
(2)Attenuation of sound through distance
● The figure on the right shows the Figure 1
attenuation of sound with distance.
This is based upon operating sound at 1m from
the source of the sound.
(e.g.)
For a type 280 outdoor unit, the sound
at 3m distance in the 50Hz range, the
specification gives 56dB(A). On the
figure to the right for the 3m distance
point proceed vertically downward to the
crossing point (a) and then horizontally
to the left to the point (b): an
attenuation of 6.8dB(A) is obtained.
Therefore 56-6.8=49.2dB(A)
Ordi
Morning
Sound Sound
level Time
(phon) (phon)
area,
40
area,
45
6:00 am to
light
8:00 am
55
area,
60
nary standards
Daytime Evening
Sound
level Time level
(phon)
45 40
8:00 am to
7:00 pm
50 45
60 55
8:00 am to
8:00 pm
70 60
(B)
Note: The values for unit operating sound are for a location with few reflecting
surfaces (bottom surface concrete)
D - 23
6. Sound-proofing measures
Night
Sound
Time level Time
(phon)
40
7:00 pm to
11:00 pm
11:00 pm to
45
following
day 6:00 am
50
8:00 pm to
11:00 pm
55
distance (m)
(A)
distance attenuation of operating sound
Special standards
Near schools or
hospitals
(approximately
50m)
Same as the
standards on the
left
5 phon lower
than the
standards on the
left