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  • BS 848-2.5(2003) : 2003

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    Superseded A superseded Standard is one, which is fully replaced by another Standard, which is a new edition of the same Standard.
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    ACOUSTICS - DETERMINATION OF SOUND POWER RADIATED INTO A DUCT BY FANS AND OTHER AIR-MOVING DEVICES - IN-DUCT METHOD

    Available format(s): 

    Superseded date:  30-04-2010

    Language(s): 

    Published date:  23-11-2012

    Publisher:  British Standards Institution

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    Table of Contents - (Show below) - (Hide below)

    Foreword
    Introduction
    1 Scope
       1.1 General
       1.2 Types of sound source
    2 Normative references
    3 Terms, definitions and symbols
    4 Uncertainty of the measurement method
    5 Test facilities and instrumentation
       5.1 General requirements
       5.2 Duct specifications
       5.3 Instrumentation
       5.4 System calibration
    6 Test arrangement
       6.1 Sampling tube mounting
       6.2 Microphone position
       6.3 Operating condition control equipment
    7 Test procedure
       7.1 Operating conditions
       7.2 Sound pressure level readings
       7.3 Measurements with and without flow straightener on
            the outlet side
       7.4 Inlet side measurements - Large fans: installation
            category D (according to ISO 5801:1997)
    8 Calculations
       8.1 Average sound pressure level
       8.2 Sound power level
    9 Information to be recorded
    10 Information to be reported
    Annex A (normative) Determination of the combined mean flow
            velocity and modal correction C[3,4]
    Annex B (normative) Determination of the signal-to-noise ratio
            of sound vs. turbulent pressure fluctuation in the test
            duct
    Annex C (normative) Computational procedures for calculating the
            A-weighted sound power level from one-third-octave-band
            sound power levels
    Annex D (informative) Example of calculation of C[3,4] for a
            given duct diameter and mean flow velocity
    Annex E (informative) Guidelines for the design and construction
            of an anechoic termination
    Annex F (informative) Evaluation of performance of anechoic
            terminations
    Annex G (informative) Sampling tube information
    Annex H (informative) Test method for small ducted fans
    Annex I (informative) Test method for large ducted fans
    Annex J (informative) Measurement of the swirl component
    Bibliography

    Abstract - (Show below) - (Hide below)

    Gives a method for testing ducted fans and other air-moving devices to determine the sound power radiated into an anechoically terminated duct on the inlet and/or outlet side of the equipment.

    General Product Information - (Show below) - (Hide below)

    Committee EH/1/4
    Development Note Partially supersedes BS 848-2(1985). Supersedes BS EN 25136 and 00/561592 DC. (04/2003)
    Document Type Standard
    Publisher British Standards Institution
    Status Superseded
    Superseded By
    Supersedes

    Standards Referencing This Book - (Show below) - (Hide below)

    ISO 3744:2010 Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Engineering methods for an essentially free field over a reflecting plane
    ISO 3743-2:1994 Acoustics Determination of sound power levels of noise sources using sound pressure Engineering methods for small, movable sources in reverberant fields Part 2: Methods for special reverberation test rooms
    ISO 7574-4:1985 Acoustics — Statistical methods for determining and verifying stated noise emission values of machinery and equipment — Part 4: Methods for stated values for batches of machines
    IEC 60942:2003 Electroacoustics - Sound calibrators
    ISO 266:1997 Acoustics — Preferred frequencies
    ISO 3740:2000 Acoustics Determination of sound power levels of noise sources Guidelines for the use of basic standards
    ISO 7574-1:1985 Acoustics — Statistical methods for determining and verifying stated noise emission values of machinery and equipment — Part 1: General considerations and definitions
    ISO 5801:2017 Fans — Performance testing using standardized airways
    ISO 3746:2010 Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Survey method using an enveloping measurement surface over a reflecting plane
    ISO 7574-3:1985 Acoustics — Statistical methods for determining and verifying stated noise emission values of machinery and equipment — Part 3: Simple (transition) method for stated values for batches of machines
    ISO 3741:2010 Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Precision methods for reverberation test rooms
    ISO 7235:2003 Acoustics — Laboratory measurement procedures for ducted silencers and air-terminal units — Insertion loss, flow noise and total pressure loss
    ISO 3745:2012 Acoustics — Determination of sound power levels and sound energy levels of noise sources using sound pressure — Precision methods for anechoic rooms and hemi-anechoic rooms
    IEC 61260:1995 Electroacoustics - Octave-band and fractional-octave-band filters
    IEC 60651:1979+AMD1:1993+AMD2:2000 CSV Sound level meters
    ISO 3743-1:2010 Acoustics Determination of sound power levels and sound energy levels of noise sources using sound pressure Engineering methods for small movable sources in reverberant fields Part 1: Comparison method for a hard-walled test room
    ASHRAE 74 : 1998 METHOD OF MEASURING SOLAR-OPTICAL PROPERTIES OF MATERIALS
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