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    Sound and Noise

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    sipurman
    This document discusses various topics related to sound and noise, including definitions of sound and noise, how sound propagates, the anatomy of the ear, sound pressure levels, and noise measurement and control techniques. It addresses topics such as how sound travels, how the ear perceives sound, units used to measure sound like decibels and frequencies, acceptable noise exposure limits, and strategies to reduce noise levels. Measurement and reporting standards are also covered along with mapping noise and approaches to controlling noise at its source, in its transmission path, or with protective devices.

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    Sound and Noise

    Uploaded by

    sipurman
    20 views42 pages
    This document discusses various topics related to sound and noise, including definitions of sound and noise, how sound propagates, the anatomy of the ear, sound pressure levels, and noise measurement and control techniques. It addresses topics such as how sound travels, how the ear perceives sound, units used to measure sound like decibels and frequencies, acceptable noise exposure limits, and strategies to reduce noise levels. Measurement and reporting standards are also covered along with mapping noise and approaches to controlling noise at its source, in its transmission path, or with protective devices.

    Original Description:

    presentasi tentang suara dan kebisingan

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    This document discusses various topics related to sound and noise, including definitions of sound and noise, how sound propagates, the anatomy of the ear, sound pressure levels, and noise measurement and control techniques. It addresses topics such as how sound travels, how the ear perceives sound, units used to measure sound like decibels and frequencies, acceptable noise exposure limits, and strategies to reduce noise levels. Measurement and reporting standards are also covered along with mapping noise and approaches to controlling noise at its source, in its transmission path, or with protective devices.

    Copyright:

    © All Rights Reserved
    Download as PPT, PDF, TXT or read online from Scribd
    Download as ppt, pdf, or txt
    20 views42 pages

    Sound and Noise

    Uploaded by

    sipurman
    This document discusses various topics related to sound and noise, including definitions of sound and noise, how sound propagates, the anatomy of the ear, sound pressure levels, and noise measurement and control techniques. It addresses topics such as how sound travels, how the ear perceives sound, units used to measure sound like decibels and frequencies, acceptable noise exposure limits, and strategies to reduce noise levels. Measurement and reporting standards are also covered along with mapping noise and approaches to controlling noise at its source, in its transmission path, or with protective devices.

    Copyright:

    © All Rights Reserved
    Download as PPT, PDF, TXT or read online from Scribd
    Download as ppt, pdf, or txt
    of 42

    Akustika dan Kebisingan

    What is sound?
    What is noise?
    Sound Propagation
    Sound Propagation
    Ear
    Anatomy
    Sound

    τ = 35 ms
    Amplification in outer and middle ear
    Structure Bourne sound
    • Question:
    Why does your voice sound different on a tape
    recording?

    • Answer:
    When you hear yourself speak you are hearing
    some extra vibration produced by the passage
    of sound waves through your skull. Your voice as
    played by a tape recorder is the way it sounds to
    someone else, who receives the sound waves
    only through the air.
    Sound localization
    • Question:
    How can you tell the direction of a sound?

    • Answer:
    1. Time differences
    2. Level differences
    3. Head Related Transfer Function
    Range of sound pressure

    Threshold
    of Pain

    Threshold
    of Hearing
    Range of sound pressure
    dB - decibel
    Perception of dB
    Addition of noise level
    Addition of noise level
    Subtraction of noise level
    Subtraction of noise level
    Addition of many dB values
    Lets hear the rumble
    Wave length and Frequency
    Lets hear the rumble
    Equal loudness countour
    40 dB Equal loudness contour & A-weighting
    Frequency Weighting
    Location of transducer
    Exposure limit (international & Indonesia)
    Halving rate : Increasing noise level by 3 dB(A)
    reducing exposure time by half

    Hours dB (A)
    8 85
    4 88
    2 91
    1 94
    0,5 97
    Exposure limit (USA)
    Halving rate : Increasing noise level by 5 dB(A)
    reducing exposure time by half
    Hours dB (A)
    8 90
    4 95
    2 100
    1 105
    0,5 110
    Energy parameter
    Energy parameter
    The Measurement Report
    The Measurement Report
    A good measurement report should contain at least the
    following information:
    1. A sketch of the measurement site showing applicable
    dimensions (e.g. size of room, machine dimensions),
    the location of the microphone and object being measured.
    2. Standard(s) to which measurements are made.
    3. Type and serial number of instruments) used.
    4. Method of calibration.
    5. Weighting networks and detector responses used.
    6. Description of type of sound (e.g. impulsive, continuous,tones etc.
    7. Background noise level.
    8. Environmental conditions (e.g. type of sound field, atmospheric
    conditions).
    9. Data on object being measured (e.g. machine type, load, speed
    etc.)
    10. Date when measurements were performed.
    Noise Mapping
    Noise Control

    1. Eliminate or reduce
    the noise at its
    source.
    2. Block the sound
    transmission path.
    3. Hearing Protector.
    4. Administrative
    control.
    Home work
    1. Setelah beraktivitas mengapa badan kita
    rasakan lebih segar bila kita mandi
    dengan air panas dibanding dengan air
    dingin.
    2. Mengapa WBGT lebih sesuai untuk
    pengukuran heat exposure dibandingkan
    termometer biasa.
    3. Apa beda illuminance dan luminance

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