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GB/T 4214.9-2021   Test method for noise of household and similar electrical appliances—Particular requirements for fans (English Version)
Standard No.: GB/T 4214.9-2021 Status:valid remind me the status change

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Language:English File Format:PDF
Word Count: 6000 words Price(USD):180.0 remind me the price change

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Implemented on:2021-3-9 Delivery: via email in 1 business day
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Standard No.: GB/T 4214.9-2021
English Name: Test method for noise of household and similar electrical appliances—Particular requirements for fans
Chinese Name: 家用和类似用途电器噪声测试方法 风扇的特殊要求
Chinese Classification: Z32    Noise and vibration test methods
Professional Classification: GB    National Standard
Issued by: SAMR; SAC
Issued on: 2021-03-09
Implemented on: 2021-3-9
Status: valid
Language: English
File Format: PDF
Word Count: 6000 words
Price(USD): 180.0
Delivery: via email in 1 business day
GB/T 4214 Test method for noise of household and similar electrical appliances is divided into nine parts: ——Part 1: General requirements; —— Part 2: Particular requirements for vacuum cleaners; —— Part 3: Particular requirements for dishwashers; —— Part 4: Particular requirements for washing machines and spin extractors; ——Part 5: Particular requirements for electric shavers; ——Part 6: Particular requirements for electric hair care appliances; ——Part 7: Particular requirements for washing machines and spin extractors; ——Part 8: Particular requirements for electric cooking ranges, ovens, grills, microwave ovens and any combination of these; ——Part 9: Particular requirements for fans. This is part 9 of GB/T 4214. This part shall be used in combination with GB/T 4214.1-2017. The clauses state "applicable", that means corresponding clauses of GB/T 4214.1-2017 are applicable to this part; when the clauses state "replacement" give priority to the clauses in this part; when the clauses state "addition", that means not only the corresponding clauses in GB/T 4214.1-2017, but also added clauses of this part shall be complied. This part is developed in accordance with the rules given in GB/T 1.1-2009. This part is modified in relation to IEC 60704-2-7:2020 Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 2-7: Particular requirements for fans. The technical deviations between this part and IEC 60704-2-7:2020 and their reasons are as follows: ——Floor fans are added to the scope according to the situation of China's fan industry (1.1.1 of Clause 1); ——The terms and definitions of 3.115 floor fans are added according to the situation of China's fan industry (Clause 3); ——The definitions of comfort fans in IEC 60879:2019 are used many times in 3.101-3.109, so the terms and definitions of 3.116 comfort fans are added for ease of use and understanding (Clause 3); ——The test height of adjustable table fans, floor fans and pedestal fans are described in detail, and the cases that can swing automatically are listed. Reason: clarify the test height of the adjustable height table fans, floor fan s and pedestal fans, and the condition of automatic swing (see 6.4.1); ——Ceiling bracket fans are added, because the installation of the ceiling bracket fans and ceiling fans are the same (6.5.1); ——The installation modes of wall bracket fans are added to clarify the installation modes of wall bracket fans (6.5.4); ——7.1.1 The application range of the measuring surface is increased by the floor fans. Reason: The above types of fans are added to the scope in Clause 1 (7.1.1); ——7.1.6 The high pedestal fans applicable to the measurement surface is explained. It is applicable to the high pedestal fans whose geometric center of the reference body is more than 1 m above the ground and which cannot be adjusted. Reason: clarify the range of the high pedestal fans (7.1.6). The following editorial changes have been made in this part: ——In order to unify the name of this series of standards, the name of this part is revised to Test method for noise of household and similar electrical appliances - Particular requirements for fans. This part was proposed by the China National Light Industry Council. This part is under the jurisdiction of the National Technical Committee on Household Appliances Condenser of Standardization Administration of China. Test method for noise of household and similar electrical appliances - Particular requirements for fans 1 Scope and object This clause of GB/T 4214.1-2017 is applicable except as follows. 1.1 Scope 1.1.1 General Replacement: This part of GB/T 4214 applies to electrical fans (including their accessories and their component parts) for household and similar use, designed for AC or DC supply. The motor, the impeller and their housing, if any, form a single unit. This part is applicable to: ——conventional fans; ——table fans; ——pedestal fan; ——ceiling fan; ——bladeless fans; ——wall bracket fans; ——ceiling bracket fans; ——louver fans; ——tower fans; ——ventilating and partition ventilating fans; ——floor fans. This part does not apply to: ——fans that are part of a ventilation system; ——fans designed exclusively for industrial purposes; ——fans that are part of an appliance (for example cooling fans); ——fans with additional functions (for example heating, humidifying). Limitations for the use of this test code are given in Clause 1 of GB/T 4214.1-2017. 1.1.2 Type of noise Replacement: The methods specified in GB/T 6881.2- 2017, GB/T 6881.3-2002 and GB/T 3767-2016 can be used for measuring noise emitted by fans. 1.1.3 Size of Source Replacement: The method specified in GB/T 3767-2016 is applicable to noise Sources of any size. When applying GB/T 6881.2-2017 and GB/T 6881.3-2002, care should be taken to ensure that the maximum size of the appliance under test fulfils the requirements specified in 1.2 of GB/T 6881.2-2017 and 1.3 of GB/T 6881.3-2002. 1.2 Object Addition: This part describes the determination of the noise emission of household fans in normal operation at maximum speed. Other speeds can, in addition, be used. Requirements for the declaration of noise emission values are not within the scope of this part. The aim of this part is to give direction for measuring the noise in a room resulting from the operation of a fan. Note 101: For determining and verifying noise emission values declared in product specifications, see IEC 60704-3. 1.3 Measurement uncertainty Replacement: The estimated values of standard deviations of sound power levels, determined according to this standard, see Table 101: Table 101 Standard deviations of sound power levels Standard deviation/dB σr(repeatability) σR(repeatability) 0.4 1.0 Addition: 1.101 Standard deviation for declaration and verification For the purpose of determining and verifying declared noise emission values according to IEC 60704-3, the values indicated in Table 102 apply: Table 102 Standard deviations for declaration and verification Standard deviation/dB σP (production) σt (total) σM (reference) 0.5-1.0 1.0-1.4 1.5 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated reference, the latest edition of the referenced documents (including any amendments) applies. This clause of GB/T 4214.1- 2017 is applicable except as follows: Replacement: GB/T 3767-2016 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 3744:2010, IDT) GB/T 6881.2-2017 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 (ISO 3743-1:2010, IDT) Addition: GB/T 4214.1-2017 Test method for noise of household and similar electrical appliances - General requirements (IEC 60704-1:2010, IDT) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. This clause of GB/T 4214.1- 2017 is applicable except as follows: Addition: 3.101 conventional fan comfort fan with a propeller having two or more blades, with free inlet and outlet of air [Source: IEC 60879:2019, 3.2] 3.102 tower fan comfort fan for use directly on the floor having a vertically elongated design of the cross flow type, tangential type or centrifugal type or impeller type with a free inlet and outlet of air [Source: IEC 60879:2019, 3.3] 3.103 bladeless fan comfort fan of any type that is not fitted with a propeller [Source: IEC 60879:2019, 3.4] 3.104 ceiling fan conventional fan provided with a device for suspension from the ceiling of a room so that the blades rotate in a horizontal plane with the diameter of the blade not larger than 1800 mm [Source: IEC 60879:2019, 3.5] 3.105 table fan comfort fan intended for use on a table Note 1: Table fans have a maximum adjustable or non-adjustable height not greater than 1200mm. Note 2: Adjustment of height, position and oscillation can be possible. [Source: IEC 60879:2019, 3.6, modified − Note 2 to entry added] 3.106 pedestal fan comfort fan mounted on a pedestal of fixed or variable height Note 1: Pedestal fans have a maximum adjustable height or non-adjustable height greater than 1200 mm Note 2: Adjustment of height, position and oscillation can be possible. [Source: IEC 60879:2019, 3.7, modified – Note 2 to entry added] 3.107 wall bracket fan comfort fan for mounting on the wall [Source: IEC 60879:2019, 3.8] 3.108 ceiling bracket fan comfort fan for mounting on the ceiling [Source: IEC 60879:2019, 3.9] 3.109 louver fan comfort fan having a moving louvre which provides a continuously changing multi-directional air flow [Source: IEC 60879:2019, 3.10] 3.110 ventilating fan fan intended to displace air either from one side of a partition to the other, or within a duct installed either on the fan inlet or on the fan outlet or both [Source: IEC 60665:2018, 3.2] 3.111 partition ventilating fan type A ventilating fan ventilating fan installed in or upon the aperture of a partition in order to displace air from one side of the partition to the other side, both the sides being free spaces [Source: IEC 60665:2008, 3.3] 3.112 free inlet partition ventilating fan type B ventilating fan ventilating fan with a direct inlet from free space and with ducted outlet [Source: IEC 60665:2018, 3.4] 3.113 free outlet partition ventilating fan type C ventilating fan ventilating fan with ducted inlet, and with direct outlet to free space [Source: IEC 60665:2018, 3.5] 3.114 fully ducted ventilating fan type D ventilating fan ventilating fan with ducted inlet and ducted outlet [Source: IEC 60665:2018, 3.6] 3.115 floor fan fan having two or more blades and height adjuster for worktable or ground mounting, driven by a motor for blades to rotate and intended for use with free inlet and outlet of air 3.116 comfort fan fans that are mainly designed to generate air flow around or on a part of the human body to make the human body feel cool and comfortable, including fans that can perform additional functions such as lighting Note: Comfort fans are also referred to as "fans" in this part. [Source: IEC 60879:2019, 3.1] 4 Measurement methods and acoustical environments This clause of GB/T 4214.1-2017 is applicable except as follows: 4.2 Direct method Addition: If pure tone components are present in the noise emitted by the Source, the estimated standard deviation of the measured sound pressure levels in the special reverberation room may increase. In such cases, additional microphone positions or Source positions may be necessary, such as those specified in GB/T 6881.3-2002. 4.3 Comparison method Addition: If pure tone components are present in the noise emitted by the Source, the estimated standard deviation of the measured sound pressure levels in the hard-walled test room or in the special reverberation room may increase. In such cases, additional microphone positions or Source positions may be necessary, such as those specified in GB/T 6881.2-2017 or GB/T 6881.3-2002.
Foreword I 1 Scope and object 2 Normative references 3 Terms and definitions 4 Measurement methods and acoustical environments 5 Instrumentation 6 Operation and location of appliances under test 7 Measurement of sound pressure levels 8 Calculation of sound pressure and sound power levels 9 Information to be recorded 10 Information to be reported Appendixes Annex B (Normative) Test enclosure Bibliography
Referred in GB/T 4214.9-2021:
*GB/T 3767-2016 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
*GB/T 6881.2-2017 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-Comparison method for a hard-walled test room
*GB/T 4214.1-2017 Test method for noise of household and similar electrical appliances―General requirements
GB/T 4214.9-2021 is referred in:
*QJ 20422.4-2016 Environment test methods for spacecraft unit- Part 4: Magnetic test
*GJB 2696-1996 Interface of Ground-base TT&C equipment for missile and spacecraft flight mission
*GB 19778-2005 Packaging glass containers—Release of lead cadmium arsenic and antimony—Permissible limits
*GB/T 13344-1992 Downhole drill hammers and bils
*GB/T 13344-2010 Downhole drill hammers and bits
*GB/T 13344-2019 Down-the-hole hammers and bits
*YY/T 0466.1-2009 Medical devices - Symbols to be used with medical device labels, labelling and information to be supplied - Part 1: General requirements
*YY/T 0466.1-2016 Medical devices - Symbols to be used with medical device labels, labelling and information to be supplied - Part 1: General requirements
*YY/T 0466.1-2023 Medical devices―Symbols to be used with information to be supplied by the manufacturer―Part 1:General requirements
*GB/T 14480.3-2008 Non-destructive testing - Equipment for eddy current examination - Part 3: System characteristics and verification
*GB/T 14480.3-2020 Non-destructive testing instruments—Equipment for eddy current examination—Part 3:System characteristics and verification
*YY 0666-2008 Method for the test of sharpness and strength of needles tips
*GB/T 7064-1996 Requirements for turbine type synchronous machine
*GB/T 7064-2002 Requirements for turbine type synchronous machine
*GB/T 7064-2017 Specific requirements for cylindrical rotor synchronous machines
*FZ/T 01026-1993 Quantitative Chemical Analysis of Quaternary Fibre Mixtures
*FZ/T 01026-2009 Textiles—Quantitative chemical analysis—Quaternary fibre mixtures
*FZ/T 01026-2017 Textiles - Quantitative chemical analysis - Multi-component fibre mixtures
*GM/T 0005-2012 Randomness Test Specification
*GB/T 9766.6-2008 Test method for tyre valve - Part 6: Test method for core
*GB/T 9766.6-2021 Test method for tyre valve - Part 6: Test method for core
*GB/T 18801-2002 Air cleaner
*GB/T 246-1997 Metallic materials--Tube--Flattening test
*GB/T 246-1982 Method for flattening test on tubes of metals
*GB/T 246-2007 Metal materials – Tube - Flattening test
*GB/T 19606-2024 Noise limit value for household and similar electrical appliances
Code of China
Standard
GB/T 4214.9-2021  Test method for noise of household and similar electrical appliances—Particular requirements for fans (English Version)
Standard No.GB/T 4214.9-2021
Statusvalid
LanguageEnglish
File FormatPDF
Word Count6000 words
Price(USD)180.0
Implemented on2021-3-9
Deliveryvia email in 1 business day
Detail of GB/T 4214.9-2021
Standard No.
GB/T 4214.9-2021
English Name
Test method for noise of household and similar electrical appliances—Particular requirements for fans
Chinese Name
家用和类似用途电器噪声测试方法 风扇的特殊要求
Chinese Classification
Z32
Professional Classification
GB
ICS Classification
Issued by
SAMR; SAC
Issued on
2021-03-09
Implemented on
2021-3-9
Status
valid
Superseded by
Superseded on
Abolished on
Superseding
Language
English
File Format
PDF
Word Count
6000 words
Price(USD)
180.0
Keywords
GB/T 4214.9-2021, GB 4214.9-2021, GBT 4214.9-2021, GB/T4214.9-2021, GB/T 4214.9, GB/T4214.9, GB4214.9-2021, GB 4214.9, GB4214.9, GBT4214.9-2021, GBT 4214.9, GBT4214.9
Introduction of GB/T 4214.9-2021
GB/T 4214 Test method for noise of household and similar electrical appliances is divided into nine parts: ——Part 1: General requirements; —— Part 2: Particular requirements for vacuum cleaners; —— Part 3: Particular requirements for dishwashers; —— Part 4: Particular requirements for washing machines and spin extractors; ——Part 5: Particular requirements for electric shavers; ——Part 6: Particular requirements for electric hair care appliances; ——Part 7: Particular requirements for washing machines and spin extractors; ——Part 8: Particular requirements for electric cooking ranges, ovens, grills, microwave ovens and any combination of these; ——Part 9: Particular requirements for fans. This is part 9 of GB/T 4214. This part shall be used in combination with GB/T 4214.1-2017. The clauses state "applicable", that means corresponding clauses of GB/T 4214.1-2017 are applicable to this part; when the clauses state "replacement" give priority to the clauses in this part; when the clauses state "addition", that means not only the corresponding clauses in GB/T 4214.1-2017, but also added clauses of this part shall be complied. This part is developed in accordance with the rules given in GB/T 1.1-2009. This part is modified in relation to IEC 60704-2-7:2020 Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 2-7: Particular requirements for fans. The technical deviations between this part and IEC 60704-2-7:2020 and their reasons are as follows: ——Floor fans are added to the scope according to the situation of China's fan industry (1.1.1 of Clause 1); ——The terms and definitions of 3.115 floor fans are added according to the situation of China's fan industry (Clause 3); ——The definitions of comfort fans in IEC 60879:2019 are used many times in 3.101-3.109, so the terms and definitions of 3.116 comfort fans are added for ease of use and understanding (Clause 3); ——The test height of adjustable table fans, floor fans and pedestal fans are described in detail, and the cases that can swing automatically are listed. Reason: clarify the test height of the adjustable height table fans, floor fan s and pedestal fans, and the condition of automatic swing (see 6.4.1); ——Ceiling bracket fans are added, because the installation of the ceiling bracket fans and ceiling fans are the same (6.5.1); ——The installation modes of wall bracket fans are added to clarify the installation modes of wall bracket fans (6.5.4); ——7.1.1 The application range of the measuring surface is increased by the floor fans. Reason: The above types of fans are added to the scope in Clause 1 (7.1.1); ——7.1.6 The high pedestal fans applicable to the measurement surface is explained. It is applicable to the high pedestal fans whose geometric center of the reference body is more than 1 m above the ground and which cannot be adjusted. Reason: clarify the range of the high pedestal fans (7.1.6). The following editorial changes have been made in this part: ——In order to unify the name of this series of standards, the name of this part is revised to Test method for noise of household and similar electrical appliances - Particular requirements for fans. This part was proposed by the China National Light Industry Council. This part is under the jurisdiction of the National Technical Committee on Household Appliances Condenser of Standardization Administration of China. Test method for noise of household and similar electrical appliances - Particular requirements for fans 1 Scope and object This clause of GB/T 4214.1-2017 is applicable except as follows. 1.1 Scope 1.1.1 General Replacement: This part of GB/T 4214 applies to electrical fans (including their accessories and their component parts) for household and similar use, designed for AC or DC supply. The motor, the impeller and their housing, if any, form a single unit. This part is applicable to: ——conventional fans; ——table fans; ——pedestal fan; ——ceiling fan; ——bladeless fans; ——wall bracket fans; ——ceiling bracket fans; ——louver fans; ——tower fans; ——ventilating and partition ventilating fans; ——floor fans. This part does not apply to: ——fans that are part of a ventilation system; ——fans designed exclusively for industrial purposes; ——fans that are part of an appliance (for example cooling fans); ——fans with additional functions (for example heating, humidifying). Limitations for the use of this test code are given in Clause 1 of GB/T 4214.1-2017. 1.1.2 Type of noise Replacement: The methods specified in GB/T 6881.2- 2017, GB/T 6881.3-2002 and GB/T 3767-2016 can be used for measuring noise emitted by fans. 1.1.3 Size of Source Replacement: The method specified in GB/T 3767-2016 is applicable to noise Sources of any size. When applying GB/T 6881.2-2017 and GB/T 6881.3-2002, care should be taken to ensure that the maximum size of the appliance under test fulfils the requirements specified in 1.2 of GB/T 6881.2-2017 and 1.3 of GB/T 6881.3-2002. 1.2 Object Addition: This part describes the determination of the noise emission of household fans in normal operation at maximum speed. Other speeds can, in addition, be used. Requirements for the declaration of noise emission values are not within the scope of this part. The aim of this part is to give direction for measuring the noise in a room resulting from the operation of a fan. Note 101: For determining and verifying noise emission values declared in product specifications, see IEC 60704-3. 1.3 Measurement uncertainty Replacement: The estimated values of standard deviations of sound power levels, determined according to this standard, see Table 101: Table 101 Standard deviations of sound power levels Standard deviation/dB σr(repeatability) σR(repeatability) 0.4 1.0 Addition: 1.101 Standard deviation for declaration and verification For the purpose of determining and verifying declared noise emission values according to IEC 60704-3, the values indicated in Table 102 apply: Table 102 Standard deviations for declaration and verification Standard deviation/dB σP (production) σt (total) σM (reference) 0.5-1.0 1.0-1.4 1.5 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated reference, the latest edition of the referenced documents (including any amendments) applies. This clause of GB/T 4214.1- 2017 is applicable except as follows: Replacement: GB/T 3767-2016 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 3744:2010, IDT) GB/T 6881.2-2017 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 (ISO 3743-1:2010, IDT) Addition: GB/T 4214.1-2017 Test method for noise of household and similar electrical appliances - General requirements (IEC 60704-1:2010, IDT) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. This clause of GB/T 4214.1- 2017 is applicable except as follows: Addition: 3.101 conventional fan comfort fan with a propeller having two or more blades, with free inlet and outlet of air [Source: IEC 60879:2019, 3.2] 3.102 tower fan comfort fan for use directly on the floor having a vertically elongated design of the cross flow type, tangential type or centrifugal type or impeller type with a free inlet and outlet of air [Source: IEC 60879:2019, 3.3] 3.103 bladeless fan comfort fan of any type that is not fitted with a propeller [Source: IEC 60879:2019, 3.4] 3.104 ceiling fan conventional fan provided with a device for suspension from the ceiling of a room so that the blades rotate in a horizontal plane with the diameter of the blade not larger than 1800 mm [Source: IEC 60879:2019, 3.5] 3.105 table fan comfort fan intended for use on a table Note 1: Table fans have a maximum adjustable or non-adjustable height not greater than 1200mm. Note 2: Adjustment of height, position and oscillation can be possible. [Source: IEC 60879:2019, 3.6, modified − Note 2 to entry added] 3.106 pedestal fan comfort fan mounted on a pedestal of fixed or variable height Note 1: Pedestal fans have a maximum adjustable height or non-adjustable height greater than 1200 mm Note 2: Adjustment of height, position and oscillation can be possible. [Source: IEC 60879:2019, 3.7, modified – Note 2 to entry added] 3.107 wall bracket fan comfort fan for mounting on the wall [Source: IEC 60879:2019, 3.8] 3.108 ceiling bracket fan comfort fan for mounting on the ceiling [Source: IEC 60879:2019, 3.9] 3.109 louver fan comfort fan having a moving louvre which provides a continuously changing multi-directional air flow [Source: IEC 60879:2019, 3.10] 3.110 ventilating fan fan intended to displace air either from one side of a partition to the other, or within a duct installed either on the fan inlet or on the fan outlet or both [Source: IEC 60665:2018, 3.2] 3.111 partition ventilating fan type A ventilating fan ventilating fan installed in or upon the aperture of a partition in order to displace air from one side of the partition to the other side, both the sides being free spaces [Source: IEC 60665:2008, 3.3] 3.112 free inlet partition ventilating fan type B ventilating fan ventilating fan with a direct inlet from free space and with ducted outlet [Source: IEC 60665:2018, 3.4] 3.113 free outlet partition ventilating fan type C ventilating fan ventilating fan with ducted inlet, and with direct outlet to free space [Source: IEC 60665:2018, 3.5] 3.114 fully ducted ventilating fan type D ventilating fan ventilating fan with ducted inlet and ducted outlet [Source: IEC 60665:2018, 3.6] 3.115 floor fan fan having two or more blades and height adjuster for worktable or ground mounting, driven by a motor for blades to rotate and intended for use with free inlet and outlet of air 3.116 comfort fan fans that are mainly designed to generate air flow around or on a part of the human body to make the human body feel cool and comfortable, including fans that can perform additional functions such as lighting Note: Comfort fans are also referred to as "fans" in this part. [Source: IEC 60879:2019, 3.1] 4 Measurement methods and acoustical environments This clause of GB/T 4214.1-2017 is applicable except as follows: 4.2 Direct method Addition: If pure tone components are present in the noise emitted by the Source, the estimated standard deviation of the measured sound pressure levels in the special reverberation room may increase. In such cases, additional microphone positions or Source positions may be necessary, such as those specified in GB/T 6881.3-2002. 4.3 Comparison method Addition: If pure tone components are present in the noise emitted by the Source, the estimated standard deviation of the measured sound pressure levels in the hard-walled test room or in the special reverberation room may increase. In such cases, additional microphone positions or Source positions may be necessary, such as those specified in GB/T 6881.2-2017 or GB/T 6881.3-2002.
Contents of GB/T 4214.9-2021
Foreword I 1 Scope and object 2 Normative references 3 Terms and definitions 4 Measurement methods and acoustical environments 5 Instrumentation 6 Operation and location of appliances under test 7 Measurement of sound pressure levels 8 Calculation of sound pressure and sound power levels 9 Information to be recorded 10 Information to be reported Appendixes Annex B (Normative) Test enclosure Bibliography
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Keywords:
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