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ASTM E477-06

(Test Method)

Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers

Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers

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1.1 This test method covers the laboratory testing of some of the acoustical properties of sound attenuating devices including duct liner materials, integral ducts, and in-duct absorptive straight and elbow silencers used in the ventilation systems of buildings. Procedures are described for the measurement of acoustical insertion loss, airflow generated noise, and pressure drop as a function of airflow.
1.2 Excluded from the scope are reactive mufflers and those designed for uses other than in ventilation systems, such as automobile mufflers.
1.3 This test method includes a provision for a simulated semi-reflective plenum to fit around thin-walled duct and silencer test specimens, since the acoustical environments around such thin-walled specimens can affect the measured insertion loss.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
1.4 This method tests the performance of the specimen in well-defined and controlled conditions. If the specimen is installed in the field in any different manner, the results may be different. This standard does not provide estimating procedures for determining the actual installed performance of the specimen field conditions.

General Information

Status
Historical
Publication Date
31-Jan-2006
ICS
91.120.20 - Acoustics in building. Sound insulation
Technical Committee
E33 - Building and Environmental Acoustics
Drafting Committee
E33.08 - Mechanical and Electrical System Noise
Current Stage
Ref Project

Relations

Replaces
ASTM E477-99 - Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers
Effective Date
01-Feb-2006
Replaced By
ASTM E477-06a - Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers
Effective Date
01-May-2006
Referred By
ASTM C634-22 - Standard Terminology Relating to Building and Environmental Acoustics
Effective Date
01-Feb-2006

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ASTM E477-06 - Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated SilencersASTM E477-06 - Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers
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ASTM E477-06 - Standard Test Method for Measuring Acoustical and Airflow Performance of Duct Liner Materials and Prefabricated Silencers
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Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact ASTM
International (www.astm.org) for the latest information.
Designation: E 477 – 06
Standard Test Method for
Measuring Acoustical and Airflow Performance of Duct
1
Liner Materials and Prefabricated Silencers
This standard is issued under the fixed designation E477; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope C634 Terminology Relating to Environmental Acoustics
E90 Test Method for Laboratory Measurement ofAirborne
1.1 This test method covers the laboratory testing of some
Sound Transmission Loss of Building Partitions and Ele-
of the acoustical properties of sound attenuating devices
ments
including duct liner materials, integral ducts, and in-duct
E 795 Practices for Mounting Test Specimens During
absorptive straight and elbow silencers used in the ventilation
Sound Absorption Tests
systems of buildings. Procedures are described for the mea-
3
2.2 ANSI Standards:
surement of acoustical insertion loss, airflow generated noise,
S1.1–1994(R2004) Acoustical Terminology
and pressure drop as a function of airflow.
S1.11–2004 Specification Octave, Half-Octave and Third-
1.2 Excluded from the scope are reactive mufflers and those
Octave Band Filter Sets
designed for uses other than in ventilation systems, such as
S12.51–2002/ISO 3741:1999 Acoustics-Determination of
automobile mufflers.
Sound Power Levels of Noise Sources Using Sound
1.3 This test method includes a provision for a simulated
Pressure-Precision Method for Reverberation Rooms
semi-reflective plenum to fit around thin-walled duct and
4
2.3 AMCA Standards:
silencer test specimens, since the acoustical environments
AMCA 300 –96, Reverberant Room Method for Sound
around such thin-walled specimens can affect the measured
Testing of Fans
insertion loss.
5
2.4 ASHRAE Documents and Standards:
1.4 This standard does not purport to address all of the
2001ASHRAE Handbook, FundamentalsVolume, Chapter
safety concerns, if any, associated with its use. It is the
14, Chapter on Measurement and Instruments
responsibility of the user of this standard to establish appro-
ANSI/ASHRAE 41.3 Method for Pressure Measurement
priate safety and health practices and determine the applica-
6
2.5 NAIMA Documents and Standards:
bility of regulatory limitations prior to use.
Fibrous Glass Duct Liner Standard 3rd ed., 2002
1.5 This method tests the performance of the specimen in
well-defined and controlled conditions. If the specimen is
3. Terminology
installedinthefieldinanydifferentmanner,theresultsmaybe
3.1 Definitions—The acoustical terms used in this method
different.Thisstandarddoesnotprovideestimatingprocedures
are consistent with Terminology C634, and ANSI S1.1.
for determining the actual installed performance of the speci-
3.2 Definitions of Terms Specific to This Standard:
men field conditions.
3.2.1 acoustical duct liner material—a material that has
2. Referenced Documents soundabsorptivepropertiesandisattachedtotheinsidewallof
2 a duct to attenuate the sound that propagates down that section
2.1 ASTM Standards:
of duct.
C 384 Test Method for Impedance and Absorption of
3.2.2 airflow generated noise—thenoisecreatedbyaerody-
Acoustical Materials by Impedance Tube Method
namic turbulence caused by air flowing through a device.
C423 Test Method for Sound Absorption and Sound Ab-
3.2.3 background noise—the total of all noise sources of
sorption Coefficients by the Reverberation Room Method
interference in a system used for the production, detection,
1 3
This test method is under the jurisdiction of ASTM Committee E33 on Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
EnvironmentalAcousticsandisthedirectresponsibilityofSubcommitteeE33.08on 4th Floor, New York, NY 10036.
4
Mechanical and Electrical System Noise. Available from Air Movement and Control Association, 30 W. University Dr.,
Current edition approved Feb. 1, 2006. Published May 2006. Originally Arlington Heights, IL 60004.
5
approved in 1973. Last previous edition approved in 1999 as E477–99. Available from American Society of Heating, Refrigerating, and Air-
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Conditioning Engineers, Inc. (ASHRAE), 1791 Tullie Circle, NE, Atlanta, GA
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM 30329.
6
Standards volume information, refer to the standard’s Document Summary page on Available from North American Insulation Manufactures Association
the ASTM website. (NAIMA) 44 Canal Center Plaza, Suite 310 Alexandria, VA 22314.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

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5.1 Measurement of the sound absorption of a room is part of the procedure for other acoustical measurements, such as determining the sound power level of a noise source or the sound transmission loss of a partition. It is also used in certain calculations such as predicting the sound pressure level in a room when the sound power level of a noise source in the room is known.  
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5.3 Diffraction effects4 usually cause the apparent area of a specimen to be greater than its geometrical area, thereby increasing the coefficients measured according to this test method. When the test specimen is highly absorptive, these values may exceed unity.  
5.4 The coefficients measured by this test method should be used with caution because not only are the areas encountered in practical usage usually larger than the test specimen, but also the sound field is rarely diffuse. In the laboratory, measurements must be made under reproducible conditions, but in practical usage the conditions that determine the effective absorption are often unpredictable. Regardless of the differences and the necessity for judgment, coefficients measured by this test method have been used successfully by architects and consultants in the acoustical design of architectural spaces.  
5.5 Field Measurements—When sound absorption measurements are made in a building in which the size and shape of the room are not under the operator's control, the approximation to a diffuse sound field is not likely to be very close. This matter should be considered when assessing the accuracy of measurements made under field conditions. (See Te...
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1.2 Field Measurements—Although this test method covers laboratory measurements, the test method described in 4.1 can be used for making field measurements of the absorption of rooms (see also 5.5). A method to measure the absorption of rooms in the field is described in Test Method E2235.  
1.3 This test method includes information on laboratory accreditation (see Annex A1), asymmetrical screens (see Annex A2), and reverberation room qualification (see Annex A3).  
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1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The main part of this standard uses procedures originally developed for laboratory measurements of the sound transmission loss of partitions. These procedures assume that the rooms in which the measurements are performed have a sound field that reasonably approximates a diffuse field. Sound pressure levels in such rooms are reasonably uniform throughout the room and average levels vary inversely with the logarithm of the room sound absorption. Not all rooms will satisfy these conditions. Experience and controlled studies (1)6 have shown that the test method is applicable to smaller spaces normally used for work or living, such as rooms in multi-family dwellings, hotel guest rooms, meeting rooms, and offices with volumes less than 150 m3. The measures appropriate for such spaces are NR, NNR, and ATL. The corresponding single number ratings are NIC, NNIC and ASTC. The ATL and ASTC are measurable between larger spaces that meet a limitation on absorption in the spaces to provide uniform sound distribution.  
5.2 Annex A1 was developed for use in spaces that are very large (volume of 150 m3 or greater). Sound pressure levels during testing vary markedly across large rooms so that the degree of isolation varies strongly with distance from the common (separating) partition. This procedure evaluates the isolation observed near the partition. The appropriate measure is NR, and the appropriate single number rating is NIC.  
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FIG. 1 Direct (D) and Some Indirect or Flanking Paths (F and Dotted) in a Building  
1.2 The main part of this test method defines procedures and metrics to assess the sound isolation between two rooms or portions thereof in a building separated by a common partition or the apparent sound insulation of the separating partition, including both direct and flanking transmission paths in all cases. Appropriate measures and their single number ratings are the noise reduction (NR) and noise isolation class (NIC) which indicate the isolation with the receiving room furnished as it is during the test, the normalized noise reduction (NNR) and normalized noise isolation class (NNIC) which indicate the isolation expected if the receiving room was a normally furnished living or office space that is at least 25 m3 (especially useful when the test must be done with the receiving room unfurnished), and the apparent transmission loss (ATL) and apparent sound transmission class (ASTC) which indicate the apparent sound insulating properties of a separating partition including both the direct transmission and flanking transmission through the support structure. The measurement of ATL ...

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4.1 The sound absorption of a material that covers a flat surface depends not only on the physical properties of the material but also on the way in which the material is mounted over the surface. The mountings specified in these practices are intended to simulate in the laboratory conditions that exist in normal use.  
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5.1 This is an in situ method, that is, the measurements are made at the actual installation. The sound levels measured according to this test method should be representative for that installation and for the quantity of acoustical absorption actually, permanently present.  
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1.1 This test method covers the laboratory measurement of impact sound transmission of floor-ceiling assemblies using a standardized tapping machine. It is assumed that the test specimen constitutes the primary sound transmission path into a receiving room located directly below and that a good approximation to a diffuse sound field exists in this room.  
1.2 Measurements may be conducted on floor-ceiling assemblies of all kinds, including those with floating-floor or suspended ceiling elements, or both, and floor-ceiling assemblies surfaced with any type of floor-surfacing or floor-covering materials.  
1.3 This test method prescribes a uniform procedure for reporting laboratory test data, that is, the normalized one-third octave band sound pressure levels transmitted by the floor-ceiling assembly due to the tapping machine.  
1.4 Laboratory Accreditation—The requirements for accrediting a laboratory for performing this test method are given in Annex A2.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
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Standard Test Method for Impedance and Absorption of Acoustical Materials by Impedance Tube Method

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5.1 The acoustical impedance properties of a sound absorptive material are related to its physical properties, such as airflow resistance, porosity, elasticity, and density. As such, the measurements described in this test method are useful in basic research and product development of sound absorptive materials.  
5.2 Normal incidence sound absorption coefficients are more useful than random incidence coefficients in certain situations. They are used, for example, to predict the effect of placing material in a small enclosed space, such as inside a machine.  
5.3 Estimates of the random incidence or statistical absorption coefficients for materials can be obtained from normal incidence impedance data. For materials that are locally reacting, that is, without sound propagation inside the material parallel to its surface, statistical absorption coefficients can be estimated from specific normal acoustic impedance values using an expression derived by London (1).5 Locally reacting materials include those with high internal losses parallel with the surface such as porous or fibrous materials of high density or materials that are backed by partitioned cavities such as a honeycomb core. Formulas for estimating random incidence sound absorption properties for both locally and bulk-reacting materials, as well as for multilayer systems with and without air spaces have also been developed (2).
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1.1 This test method covers the use of an impedance tube, alternatively called a standing wave apparatus, for the measurement of impedance ratios and the normal incidence sound absorption coefficients of acoustical materials.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM C522-03(2022)(Test Method)
Standard Test Method for Airflow Resistance of Acoustical Materials

SIGNIFICANCE AND USE
5.1 The specific airflow resistance of an acoustical material is one of the properties that determine its sound-absorptive and sound-transmitting properties. Measurement of specific airflow resistance is useful during product development, for quality control during manufacture, and for specification purposes.  
5.2 Valid measurements are made only in the region of laminar airflow where, aside from random measurement errors, the airflow resistance (R = P/U) is constant. When the airflow is turbulent, the apparent airflow resistance increases with an increase of volume velocity and the term “airflow resistance” does not apply.  
5.3 The specific airflow resistance measured by this test method may differ from the specific resistance measured by the impedance tube method in Test Method E384 for two reasons. In the presence of sound, the particle velocity inside a porous material is alternating while in this test method, the velocity is constant and in one direction only. Also, the particle velocity inside a porous material is not the same as the linear velocity measured outside the specimen.
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1.1 This test method covers the measurement of airflow resistance and the related measurements of specific airflow resistance and airflow resistivity of porous materials that can be used for the absorption and attenuation of sound. Materials cover a range from thick boards or blankets to thin mats, fabrics, papers, and screens. When the material is anisotropic, provision is made for measurements along different axes of the specimen.  
1.2 This test method is designed for the measurement of values of specific airflow resistance ranging from 100 to 10 000 mks rayls (Pa·s/m) with linear airflow velocities ranging from 0.5 mm/s to 50 mm/s and pressure differences across the specimen ranging from 0.1 Pa to 250 Pa. The upper limit of this range of linear airflow velocities is a point at which the airflow through most porous materials is in partial or complete transition from laminar to turbulent flow.  
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1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4.1 Table 1 is provided for user to convert into cgs units.    
cgs acoustic ohm  
mks acoustic ohm (Pa·s/m3)  
105  
cgs rayl  
mks rayl (Pa·s/m)  
10    
cgs rayl/cm  
mks rayl/m (Pa·s/m2)  
103  
cgs rayl/in.  
mks rayl/m (Pa·s/m2)  
394  
mks rayl/in.  
mks rayl/m (Pa·s/m2)  
39.4  
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1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM E1042-22(Classification)
Standard Classification for Acoustically Absorptive Materials Applied by Trowel or Spray

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4.1 Acoustically absorptive materials are used for the control of reverberation and echoes in rooms. This standard provides a classification method for acoustically absorptive materials applied directly to surfaces by trowel or by spray.
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1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This test method specifies the procedure used to measure the masking sound in terms of A-weighted and one-third-octave-band sound pressure levels.  
1.2 The results of this test method can be used to determine if and where the masking sound meets (or does not meet) a particular specification.  
1.3 This test method does not evaluate the overall acoustical environment. It is intended only to measure and report the masking sound levels.  
1.4 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

  • Standard
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  • Standard
    4 pages
    English language
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