This document defines and compares structure-borne sound and air-borne sound. Structure-borne sound spreads through solid objects like walls via vibrations, while air-borne sound spreads through the air between 20-20,000 Hz. Common causes of structure-borne noise are vibrating sources that transmit energy through structures, while air-borne sound travels through air and may reverberate in enclosed spaces. The document also discusses sound propagation and methods to reduce structure vibration and noise transmission, such as using dampers, barriers and sound absorbing materials.

1. STRUCTURE BORNE
&
AIR BORNE SOUND
NAME MATRIC NO.
RACHAEL JOHN LEONARDI 08DPB12F1063
TAN YEE TEAN 08DPB12F1043
HO Y NAM 08DPB12F1081
THAVEN 08DPB11F2040

2. DEFINITION :
 Structure Borne Sound is the sound which spreads in
solid bodies such as walls of houses, heaters, pipes, etc.
 Transmission occurs particularly by tremors which are
conducted by vibrations.

3. DEFINITION :
 Air Borne Sound is ultimately the sound which can
spread only via the air. This can be detected, at
least by the human ear, from 20Hz - 20000Hz.

4. Common cause:
Structure-borne noise:
• Is the sound generated from a vibrating source
/impact event.
• The acoustic energy created by these vibrations is
transmitted into the structure of a building (e.g.
floors, walls, pipe-work etc.) or into mechanical
elements (e.g. metal frames, panel work, supports
etc.)
• This energy travels through solid structures and
released as air-borne noise at different locations
within the building or mechanical system.

5. acoustic energy
Sound created by Vibration (knocking table)
Example: Knocking the Table
Transmitted into the table
Released as Air Borne
Noise/Sound
Structure-borne noise:

6. Common cause:
Air-borne Sound:
• Is the sound that travels through the air and into
the surrounding environment.
• In closed environments such as rooms and
enclosures, air-borne sound may reverberate
(echo) and increase the levels of noise both in and
outside the contained space.

7. The TRANSMISSION of acoustic energy
through a medium via a SOUND WAVE.
SOUND
PROPAGATION :
Factors which affect the propagation of sound:
1. Geometric Spreading
2. Atmospheric Effects:
(a) Air Absorption
(b) Wind & Temp. Gradient

8. 3. Surface Effects:
(a) Ground Absorption
(b)Attenuation(reduction) Due to Barriers
and Trees:

9. SOUND
PROPAGATION :
METHOD
REDUCE
Reduction at the
Receiver End
Reduction of the
Transmission Path
Reduction at
Noise Source
Noise Barrier
Noise absorber

10. Reducing Effect of vibration caused
by Building Services Equipment:
• Damper can be used to reduce vibration from A/C
condenser (outdoor unit).
• Noise Barrier can applied on anywhere for purposed to
block the noise sound caused by vibration.
• Sound absorption materials can be used to
eliminated/absorbed the vibration that cause by the
B.S equipment.

11. THANK
YOU !!