Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
GB 4214 consists of several parts under the general title Test method for noise of household and similar electrical appliances, in which, Part 1 is general requirements, and the rest are particular requirements.
This part is Part 1 of GB/T 4214.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB/T 4214.1-2000 Acoustics - Household and similar electrical appliances - Test code for determination of airborne acoustical noise - Part 1: General requirements; in addition to a number of editorial changes, the following technical changes have been made with respect to GB/T 4214.1-2000 (the previous edition):
——the scope of appliances to which this standard is not applicable is modified in Clause 1 "Scope";
——the term and definition of 3.10 are added;
——the supplementary instructions are made for the test for parts and components of household appliances, including loading and testing of envelope surface (see 6.2.5, 6.4.1 and 7.1.4);
——the test method for inverter household appliances are proposed (see 6.4.1);
——the detailed description is made for the installation of wall-mounted appliances (see 6.5.4 and 7.1.2);
——the test method and the detailed description of the test cabinet are given for the wall embedded appliance test (see 6.5.5 and Annex B);
——classification and description are made for the hemispherical envelope surface; the radius is not limited to 1.5m and 2m; for small appliances and home appliance parts, a test radius of 1m may be used (see 7.1.4);
——the test method for the operating noise of non-stationary appliances is added (see 7.4.1);
——the requirements for background noise corrections are modified (see 8.2).
This part is modified in relation to IEC 60704-1: 2010 (Edition 3) Household and similar electrical appliances – Test method for noise – Part 1: General requirements.
The main technical differences between this Part and IEC 60704-1: 2010 and the relative reasons are as follows:
——the adjustments of technical difference are made to the normative references in this standard so as to adapt to the technical conditions in China. The adjustments are mainly reflected in Clause 2 "Normative references"; the specific adjustments are as follows:
• IEC 61260:1995 is replaced by GB/T 3241-2010, which is modified in relation to international standard;
• ISO 3744:1994 is replaced by GB/T 3767-1996, which is modified based upon international standard;
——the scope of non-applicable appliances are modified in Clause 1 "Scope" for the reason that household and similar air conditioners fall within the scope of this standard.
——the term and definition of 3.10 are added; the reason is that this term appears in 7.4.1.
——the supplementary instructions are made for the test for parts and components of household appliances, including loading and testing of envelope surface (see 6.2.5, 6.4.1 and 7.1.4), so as to
define the test methods for parts and components of home appliances.
——the test method for variable-frequency household appliances is proposed (see 6.4.1), so as to define the test methods for variable-frequency household appliances.
——a detailed description of the installation of wall-mounted appliances is made (see 7.1.2), so as to make clear the installation of wall-mounted appliances.
——the plan of division and combination for the selection of the hemispherical envelope surface is made, with the radius not limited to 1.5 m and 2 m. For small appliances and home appliance parts, a test radius of 1 m can be used (see 7.1.4) so that the selection method of the hemispherical envelope surface is made clear.
——the test method for the operating noise of non-stationary appliances is added (see 7.4.1) to make it clear.
——the misstatement of the calculation formula adopted in comparison method is corrected.
——Annex C is deleted, because the contents of Annex C have not been used in this standard.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This part was proposed by China National Light Industry Council.
This Part is under the jurisdiction of SAC/TC 46 National Technical Committee on Household Electric Appliances of Standardization Administration of China.
The previous edition of standard replaced by this part are as follows:
——GB/T 4214.1-2000;
——GB/T 4214-1984.
Introduction
Although the noise emitted by household appliances does not generally present a hazard to the hearing of the operator and other exposed persons, the need for standardization procedures for the determination of the noise emitted has been recognized for a long time. Such procedures should be specified, not only for special types of appliances, but also the principles should be applicable to the majority of appliances in general use.
Generally, the determination of noise levels is only part of a comprehensive testing procedure covering many aspects of the properties and performances of the appliance. It is therefore important that the requirements for noise measurements (such as test environment, instrumentation, and amount of labour involved) should be kept at a modest level.
The results of noise measurements will be used for many purposes, for example for noise declaration, as well as for comparing the noise emitted by a specific appliance to the noise emitted by other appliances of the same family. In other cases, the results will be taken as a basis for engineering action in the development stages of new pieces of equipment, or in deciding on means for sound insulation. For all purposes, it is important to specify procedures with known accuracy so that the results of measurements taken by different laboratories can be compared.
These conditions have, as far as possible, been taken into account in the amendment to this part. The measuring methods of this part are based on those described in GB/T 3767-1996, GB/T 6881.2-2002 and GB/T 6881.3-2002.
The adoption of these methods permits the use of semi-anechoic rooms, special reverberation test rooms and hard-walled test rooms. The result of the measurements is the sound power level of the appliance. Within the measuring uncertainty specific to these methods, the results from the determination under free field conditions over a reflecting plane are equal to those obtained in reverberant fields. The use of intensity methods as described in CB/T 16404 and GB/T 16404.2 is subject to special requirements.
It should be emphasized that this test code is concerned with airborne noise only. In some cases, structure-borne noise, for example transmitted to the adjoining room, may be of importance.
Household and Similar Electrical Appliances -
Test Code for the Determination of Airborne Acoustical Noise - General Requirements
1 Scope and object
1.1 Scope
1.1.1 General
The general requirements of the series standards GB/T 4214 applies to electric appliances (including their accessories or components) for household and similar use, supplied from mains or from batteries.
By similar use is understood the use in similar conditions as in households, for example in inns, coffee-houses, tea-rooms, hotels, barber or hairdresser shops, launderettes, etc., if not otherwise specified in general requirements of the series standards GB/T 4214.
This part does not apply to
——appliances, equipment or machines designed exclusively for industrial or professional purposes;
——appliances which are integrated parts of a building or its installations, such as equipment for heating and ventilating (except household fans, cooker hoods and free standing heating appliances), oil burners for central heating, pumps for water supply and for sewage systems;
Note: Household and similar air conditioning products covered by GB/T 7725 fall within the scope of this part.
——separate motors or generators;
——appliances for outdoor use.
1.1.2 Types of noise
A classification of different types of noise is given in GB/T 19052-2003. The method specified in GB/T 3767-1996 is suitable for measurements of all types of noise emitted by household appliances. The methods specified in GB/T 6881.2-2002 and GB/T 6881.3-2002 are suitable for all types of noise, except for sources of impulsive noise. This will be taken into account in the preparation of special requirements.
1.1.3 Size of the source
The method specified in GB/T 3767-1996 is applicable to noise sources of any size. Limitations for the size of the source are given in 1.3 of GB/T 6881.2-2002 and GB/T 6881.3-2002. This will be taken into account in the preparation of special requirements.
1.2 Object
This part is concerned with objective methods of engineering accuracy (grade 2 according to GB/T 19052-2003) for determining sound power levels LW, expressed in decibels (dB) with reference to a sound power of one picowatt (1 pW), of airborne acoustical noise within the specified frequency range of interest (generally including the octave bands with centre frequencies from 125 Hz to 8kHz), and for prescribed operating conditions of the appliance to be measured.
The following quantities are used:
——A-weighted sound power level, LWA; and
——octave band sound power levels.
In general, the described methods are specified for appliances without an operator present. The special requirements can specify that an operator will be present only for the (rare) cases where an appliance can only be operated, or must be fed, by an operator.
Methods for determining sound power levels with precision accuracy (grade 1 according to GB/T 19052-2003), specified for example in GB/T 6881.1-2002 and GB/T 6882-2008, are not included in this part. They may, however, be applied if the appropriate test environment and instrumentation are available.
Notes:
1 The noise values obtained under the described conditions of this part will not necessarily correspond with the noise experienced under the operational conditions of practical use.
2 For quality control during production etc., simplified methods may be appropriate. For noise reduction purposes, other measurement methods employing, for example, narrow-band analysis or intensity techniques usually will have to be applied. These methods are not covered by this part.
1.3 Measurement uncertainty
The estimated values of the standard deviations of reproducibility of sound power levels determined according to this part are given in 1.4 of GB/T 6881.2-2002 and of GB/T 6881.3-2002, and in 1.4 of GB/T 3767-1996. But for a particular family of appliances of similar size with similar operating conditions, the standard deviations of reproducibility may be smaller than these values. Hence, in special requirements, standard deviations smaller than those listed in the above standards may be stated if substantiation is available from the results of suitable interlaboratory tests.
IEC 60704: 2006 gives values of standard deviations of reproducibility for several categories of appliances.
In case of discrepancies between the measurements where the results normally remain inside the foreseen standard deviation, it will be necessary to perform measurements according to the grade of accuracy, as described in GB/T 6881.1-2002 or GB/T 6882-2008.
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 references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3241-2010 Electroacoustics - Octave-band and fractional-octave-band filters (IEC61260: 1995, MOD)
GB/T 3767-1996 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering method in an essentially free field over a reflecting plane (eqv ISO 3744: 1994)
GB/T 3785.1-2010 Electroacoustics - Sound level meters - Part 1: specifications (IEC 61672-1: 2002, IDT)
GB/T 4129-2003 Acoustics - Requirements for the performance and calibration o reference sound sources used for determination of sound power levels (ISO 6926:1999, IDT)
GB/T 6881.1-2002 Acoustics - Determination of sound power levels of noise sources using sound pressure - Precision methods for reverberation rooms (ISO 3741: 1999, IDT)
GB/T 6881.2-2002 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering methods for small, movable sources in reverberant field - Part 1: comparison method for hard-walled test rooms (ISO 3713-1: 1994, IDT)
GB/T 6881.3-2002 Acoustics - Determination of sound power levels of noise sources-using sound pressure - Engineering methods for small, movable sources in reverberant field - Part 2: Methods for special reverberation test rooms (ISO 3743-2: 1994, IDT)
GB/T 6882-2008 Acoustics - Determination of sound power levels of noise sources using pressure - Precision methods for anechoic and hemi-anechoic rooms (ISO 3745: 2003, IDT)
GB/T 19052-2003 Acoustics - Noise emitted by machinery and equipment - Rules for the drafting and presentation of a noise test code (ISO 12001: 1996, IDT)
IEC 60038:2009 IEC standard voltages
IEC 60704-3: 2006 Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 3: procedure for determining and verifying declared noise emission values
3 Terms and definitions
For the purposes of this standard, the following terms and definitions apply.
Terms and definitions pertinent to the determination of sound power levels may be found in GB/T 3767-1996, GB/T 6881.2-2002 and GB/T 6881.3-2002.
3.1
measurement time interval
portion or a multiple of an operational period or operational cycle for which the sound power levels are determined
3.2
operational period
an interval of time during which a specified process is accomplished by the appliance under test (for example washing or rinsing or drying for a dishwasher)
3.3
operational cycle
a specific sequence of operational periods occurring while the appliance under test performs a complete work cycle.
During the operational cycle, each operational period is associated with a specific process that may occur only once, or may be repeated (for example, for a dishwasher, washing and rinsing and drying)
3.4
time history
a continuous recording of the sound pressure level (for a distinct microphone position) as a function of time, which is obtained during one or more operational periods of an operational cycle
3.5
standard test operator
a person necessary for operating or feeding the appliance under test, not wearing abnormally sound absorptive clothing which might influence the sound measurements
3.6
centre of location or position of a source
the term used for describing the location or position of the source (appliance) to be tested within the test environment and, in free field environment, with respect to the co-ordinate system of microphone positions
The centre of location is such that the centre of the appliance coincides with the centre of a parallelepiped drawn around the main part of hand-held, suspended, or stand-type appliances.
The centre of location is such that the centre of the appliance coincides with the centre of a rectangle drawn around the projection of the main part of the appliance on the floor, for floor-supported appliances, and on the wall, for wall-mounted appliances.
3.7
nominal height
hn
the smallest integer multiple of 5 mm that accommodates the height of the installation opening according to the manufacturer’s installation instructions
3.8
nominal width
wn
the smallest integer multiple of 5 mm that accommodates the width of the installation opening according to the manufacturer’s installation instructions
3.9
nominal depth
dn
the smallest integer multiple of 5 mm, equal to or greater than 515 mm, that accommodates the depth of the installation opening according to the manufacturer’s installation instructions
3.10
equivalent continues sound pressure level
Leq
pressure level of continuous steady-state sound within specified period if it has the same mean acoustic pressure as that time-varying noise within the period
4 Measurement methods and acoustical environments
4.1 General
The total noise emitted by machinery or equipment and radiated in all directions to the space surrounding the machine can be characterized by the sound power of the machine. The sound power of a machine is essentially independent of the environment in which the machine is installed. Therefore, the concept of sound power level has been chosen for expressing the noise emission of appliances for household and similar purposes.
The preferred noise emission quantity is the A-weighted sound power level, LWA, in decibels (ref. 1 pW).
According to this part, two principal methods exist, the direct method and the comparison method, as described in 4.2 and 4.3 below. These two methods can be used alternatively.
Different types of environments, as described in 4.4, may be used. The special requirements may, if necessary, include one or several combinations among those available.
4.2 Direct method
The direct method can be used only for measurements in qualified test environments according to GB/T 3767-1991 for free field conditions over reflecting plane(s), and according to GB/T 6881.3-2002 for special reverberation test rooms.
With this method, the sound power level is determined
——in free field conditions over reflecting plane(s), from time-averaged sound pressure levels (on a mean-square basis) over the measurement surface and from the area of the measurement surface;
——in special reverberation test rooms, from averaged sound pressure levels, and from the reverberation time and the volume of the test room.
This method yields results expressed in A-weighted sound power levels (and in octave-band sound power levels, if required) which are calculated directly from measured sound pressure levels.
Note: This method can also be used in conjunction with more precise methods, as for instance as given in GB/T 6881.1-2002 and GB/T 6882-2008.
Foreword i
Introduction iv
1 Scope and object
1.1 Scope
1.2 Object
1.3 Measurement uncertainty
2 Normative References
3 Terms and definitions
4 Measurement methods and acoustical environments
4.1 General
4.2 Direct method
4.3 Comparison method
4.4 Acoustical environments
5 Measuring instruments
5.1 Measuring instruments
5.2 instrument of measuring environment condition
5.3 Measuring instrument for operating condition
6 Operation and positioning of tested appliance
6.1 Assembly and preprocessing of appliance
6.2 Supply of electric energy and of water or gas
6.3 Climatic conditions
6.4 Loading and operating of appliances during tests
6.5 Location and mounting of appliances
7 Measurement of sound pressure levels
7.1 Microphone array, measurement surface and RSS location for essentially free field conditions over reflecting plane(s)
7.2 Microphone array and RSS location in hard-walled test rooms
7.3 Microphone array and reference sound source (RSS) location in special reverberation test rooms
7.4 Measurement
8 Calculation of sound pressure and sound power levels
8.1 General requirements
8.2 Corrections for background noise levels
8.3 Corrections for the test environment
8.4 Calculation of sound pressure level averaged over all measuring points
8.5 Calculation of sound power levels with the comparison method
8.6 Calculation of sound power levels in essentially free field conditions over a reflecting plane
8.7 Calculation of A-weighted sound power level with the direct method in special reverberation test rooms
9 Information to be recorded
9.1 General data
9.2 Description of appliance under test
9.3 Measurement method
9.4 Acoustical test environment
9.5 Instrumentation
9.6 Assembly and pretreatment of appliance under test
9.7 Power supply, water supply, etc.
9.8 Environmental conditions
9.9 Operation of the appliance under test
9.10 Location and mounting of the appliance under test
9.11 Measuring point locations
9.12 Measurement data
9.13 Calculated values of sound pressure and sound power levels
10 Information to be reported
10.1 General data
10.2 Appliances under test
10.3 Test conditions for appliances
10.4 Acoustical data
Annex A (Normative) Standard test table
Annex B (Normative) Test enclosure
Bibliography
Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
GB 4214 consists of several parts under the general title Test method for noise of household and similar electrical appliances, in which, Part 1 is general requirements, and the rest are particular requirements.
This part is Part 1 of GB/T 4214.
This part is developed in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB/T 4214.1-2000 Acoustics - Household and similar electrical appliances - Test code for determination of airborne acoustical noise - Part 1: General requirements; in addition to a number of editorial changes, the following technical changes have been made with respect to GB/T 4214.1-2000 (the previous edition):
——the scope of appliances to which this standard is not applicable is modified in Clause 1 "Scope";
——the term and definition of 3.10 are added;
——the supplementary instructions are made for the test for parts and components of household appliances, including loading and testing of envelope surface (see 6.2.5, 6.4.1 and 7.1.4);
——the test method for inverter household appliances are proposed (see 6.4.1);
——the detailed description is made for the installation of wall-mounted appliances (see 6.5.4 and 7.1.2);
——the test method and the detailed description of the test cabinet are given for the wall embedded appliance test (see 6.5.5 and Annex B);
——classification and description are made for the hemispherical envelope surface; the radius is not limited to 1.5m and 2m; for small appliances and home appliance parts, a test radius of 1m may be used (see 7.1.4);
——the test method for the operating noise of non-stationary appliances is added (see 7.4.1);
——the requirements for background noise corrections are modified (see 8.2).
This part is modified in relation to IEC 60704-1: 2010 (Edition 3) Household and similar electrical appliances – Test method for noise – Part 1: General requirements.
The main technical differences between this Part and IEC 60704-1: 2010 and the relative reasons are as follows:
——the adjustments of technical difference are made to the normative references in this standard so as to adapt to the technical conditions in China. The adjustments are mainly reflected in Clause 2 "Normative references"; the specific adjustments are as follows:
• IEC 61260:1995 is replaced by GB/T 3241-2010, which is modified in relation to international standard;
• ISO 3744:1994 is replaced by GB/T 3767-1996, which is modified based upon international standard;
——the scope of non-applicable appliances are modified in Clause 1 "Scope" for the reason that household and similar air conditioners fall within the scope of this standard.
——the term and definition of 3.10 are added; the reason is that this term appears in 7.4.1.
——the supplementary instructions are made for the test for parts and components of household appliances, including loading and testing of envelope surface (see 6.2.5, 6.4.1 and 7.1.4), so as to
define the test methods for parts and components of home appliances.
——the test method for variable-frequency household appliances is proposed (see 6.4.1), so as to define the test methods for variable-frequency household appliances.
——a detailed description of the installation of wall-mounted appliances is made (see 7.1.2), so as to make clear the installation of wall-mounted appliances.
——the plan of division and combination for the selection of the hemispherical envelope surface is made, with the radius not limited to 1.5 m and 2 m. For small appliances and home appliance parts, a test radius of 1 m can be used (see 7.1.4) so that the selection method of the hemispherical envelope surface is made clear.
——the test method for the operating noise of non-stationary appliances is added (see 7.4.1) to make it clear.
——the misstatement of the calculation formula adopted in comparison method is corrected.
——Annex C is deleted, because the contents of Annex C have not been used in this standard.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. The issuing body of this document shall not be held responsible for identifying any or all such patent rights.
This part was proposed by China National Light Industry Council.
This Part is under the jurisdiction of SAC/TC 46 National Technical Committee on Household Electric Appliances of Standardization Administration of China.
The previous edition of standard replaced by this part are as follows:
——GB/T 4214.1-2000;
——GB/T 4214-1984.
Introduction
Although the noise emitted by household appliances does not generally present a hazard to the hearing of the operator and other exposed persons, the need for standardization procedures for the determination of the noise emitted has been recognized for a long time. Such procedures should be specified, not only for special types of appliances, but also the principles should be applicable to the majority of appliances in general use.
Generally, the determination of noise levels is only part of a comprehensive testing procedure covering many aspects of the properties and performances of the appliance. It is therefore important that the requirements for noise measurements (such as test environment, instrumentation, and amount of labour involved) should be kept at a modest level.
The results of noise measurements will be used for many purposes, for example for noise declaration, as well as for comparing the noise emitted by a specific appliance to the noise emitted by other appliances of the same family. In other cases, the results will be taken as a basis for engineering action in the development stages of new pieces of equipment, or in deciding on means for sound insulation. For all purposes, it is important to specify procedures with known accuracy so that the results of measurements taken by different laboratories can be compared.
These conditions have, as far as possible, been taken into account in the amendment to this part. The measuring methods of this part are based on those described in GB/T 3767-1996, GB/T 6881.2-2002 and GB/T 6881.3-2002.
The adoption of these methods permits the use of semi-anechoic rooms, special reverberation test rooms and hard-walled test rooms. The result of the measurements is the sound power level of the appliance. Within the measuring uncertainty specific to these methods, the results from the determination under free field conditions over a reflecting plane are equal to those obtained in reverberant fields. The use of intensity methods as described in CB/T 16404 and GB/T 16404.2 is subject to special requirements.
It should be emphasized that this test code is concerned with airborne noise only. In some cases, structure-borne noise, for example transmitted to the adjoining room, may be of importance.
Household and Similar Electrical Appliances -
Test Code for the Determination of Airborne Acoustical Noise - General Requirements
1 Scope and object
1.1 Scope
1.1.1 General
The general requirements of the series standards GB/T 4214 applies to electric appliances (including their accessories or components) for household and similar use, supplied from mains or from batteries.
By similar use is understood the use in similar conditions as in households, for example in inns, coffee-houses, tea-rooms, hotels, barber or hairdresser shops, launderettes, etc., if not otherwise specified in general requirements of the series standards GB/T 4214.
This part does not apply to
——appliances, equipment or machines designed exclusively for industrial or professional purposes;
——appliances which are integrated parts of a building or its installations, such as equipment for heating and ventilating (except household fans, cooker hoods and free standing heating appliances), oil burners for central heating, pumps for water supply and for sewage systems;
Note: Household and similar air conditioning products covered by GB/T 7725 fall within the scope of this part.
——separate motors or generators;
——appliances for outdoor use.
1.1.2 Types of noise
A classification of different types of noise is given in GB/T 19052-2003. The method specified in GB/T 3767-1996 is suitable for measurements of all types of noise emitted by household appliances. The methods specified in GB/T 6881.2-2002 and GB/T 6881.3-2002 are suitable for all types of noise, except for sources of impulsive noise. This will be taken into account in the preparation of special requirements.
1.1.3 Size of the source
The method specified in GB/T 3767-1996 is applicable to noise sources of any size. Limitations for the size of the source are given in 1.3 of GB/T 6881.2-2002 and GB/T 6881.3-2002. This will be taken into account in the preparation of special requirements.
1.2 Object
This part is concerned with objective methods of engineering accuracy (grade 2 according to GB/T 19052-2003) for determining sound power levels LW, expressed in decibels (dB) with reference to a sound power of one picowatt (1 pW), of airborne acoustical noise within the specified frequency range of interest (generally including the octave bands with centre frequencies from 125 Hz to 8kHz), and for prescribed operating conditions of the appliance to be measured.
The following quantities are used:
——A-weighted sound power level, LWA; and
——octave band sound power levels.
In general, the described methods are specified for appliances without an operator present. The special requirements can specify that an operator will be present only for the (rare) cases where an appliance can only be operated, or must be fed, by an operator.
Methods for determining sound power levels with precision accuracy (grade 1 according to GB/T 19052-2003), specified for example in GB/T 6881.1-2002 and GB/T 6882-2008, are not included in this part. They may, however, be applied if the appropriate test environment and instrumentation are available.
Notes:
1 The noise values obtained under the described conditions of this part will not necessarily correspond with the noise experienced under the operational conditions of practical use.
2 For quality control during production etc., simplified methods may be appropriate. For noise reduction purposes, other measurement methods employing, for example, narrow-band analysis or intensity techniques usually will have to be applied. These methods are not covered by this part.
1.3 Measurement uncertainty
The estimated values of the standard deviations of reproducibility of sound power levels determined according to this part are given in 1.4 of GB/T 6881.2-2002 and of GB/T 6881.3-2002, and in 1.4 of GB/T 3767-1996. But for a particular family of appliances of similar size with similar operating conditions, the standard deviations of reproducibility may be smaller than these values. Hence, in special requirements, standard deviations smaller than those listed in the above standards may be stated if substantiation is available from the results of suitable interlaboratory tests.
IEC 60704: 2006 gives values of standard deviations of reproducibility for several categories of appliances.
In case of discrepancies between the measurements where the results normally remain inside the foreseen standard deviation, it will be necessary to perform measurements according to the grade of accuracy, as described in GB/T 6881.1-2002 or GB/T 6882-2008.
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 references, the latest edition of the referenced document (including any amendments) applies.
GB/T 3241-2010 Electroacoustics - Octave-band and fractional-octave-band filters (IEC61260: 1995, MOD)
GB/T 3767-1996 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering method in an essentially free field over a reflecting plane (eqv ISO 3744: 1994)
GB/T 3785.1-2010 Electroacoustics - Sound level meters - Part 1: specifications (IEC 61672-1: 2002, IDT)
GB/T 4129-2003 Acoustics - Requirements for the performance and calibration o reference sound sources used for determination of sound power levels (ISO 6926:1999, IDT)
GB/T 6881.1-2002 Acoustics - Determination of sound power levels of noise sources using sound pressure - Precision methods for reverberation rooms (ISO 3741: 1999, IDT)
GB/T 6881.2-2002 Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering methods for small, movable sources in reverberant field - Part 1: comparison method for hard-walled test rooms (ISO 3713-1: 1994, IDT)
GB/T 6881.3-2002 Acoustics - Determination of sound power levels of noise sources-using sound pressure - Engineering methods for small, movable sources in reverberant field - Part 2: Methods for special reverberation test rooms (ISO 3743-2: 1994, IDT)
GB/T 6882-2008 Acoustics - Determination of sound power levels of noise sources using pressure - Precision methods for anechoic and hemi-anechoic rooms (ISO 3745: 2003, IDT)
GB/T 19052-2003 Acoustics - Noise emitted by machinery and equipment - Rules for the drafting and presentation of a noise test code (ISO 12001: 1996, IDT)
IEC 60038:2009 IEC standard voltages
IEC 60704-3: 2006 Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 3: procedure for determining and verifying declared noise emission values
3 Terms and definitions
For the purposes of this standard, the following terms and definitions apply.
Terms and definitions pertinent to the determination of sound power levels may be found in GB/T 3767-1996, GB/T 6881.2-2002 and GB/T 6881.3-2002.
3.1
measurement time interval
portion or a multiple of an operational period or operational cycle for which the sound power levels are determined
3.2
operational period
an interval of time during which a specified process is accomplished by the appliance under test (for example washing or rinsing or drying for a dishwasher)
3.3
operational cycle
a specific sequence of operational periods occurring while the appliance under test performs a complete work cycle.
During the operational cycle, each operational period is associated with a specific process that may occur only once, or may be repeated (for example, for a dishwasher, washing and rinsing and drying)
3.4
time history
a continuous recording of the sound pressure level (for a distinct microphone position) as a function of time, which is obtained during one or more operational periods of an operational cycle
3.5
standard test operator
a person necessary for operating or feeding the appliance under test, not wearing abnormally sound absorptive clothing which might influence the sound measurements
3.6
centre of location or position of a source
the term used for describing the location or position of the source (appliance) to be tested within the test environment and, in free field environment, with respect to the co-ordinate system of microphone positions
The centre of location is such that the centre of the appliance coincides with the centre of a parallelepiped drawn around the main part of hand-held, suspended, or stand-type appliances.
The centre of location is such that the centre of the appliance coincides with the centre of a rectangle drawn around the projection of the main part of the appliance on the floor, for floor-supported appliances, and on the wall, for wall-mounted appliances.
3.7
nominal height
hn
the smallest integer multiple of 5 mm that accommodates the height of the installation opening according to the manufacturer’s installation instructions
3.8
nominal width
wn
the smallest integer multiple of 5 mm that accommodates the width of the installation opening according to the manufacturer’s installation instructions
3.9
nominal depth
dn
the smallest integer multiple of 5 mm, equal to or greater than 515 mm, that accommodates the depth of the installation opening according to the manufacturer’s installation instructions
3.10
equivalent continues sound pressure level
Leq
pressure level of continuous steady-state sound within specified period if it has the same mean acoustic pressure as that time-varying noise within the period
4 Measurement methods and acoustical environments
4.1 General
The total noise emitted by machinery or equipment and radiated in all directions to the space surrounding the machine can be characterized by the sound power of the machine. The sound power of a machine is essentially independent of the environment in which the machine is installed. Therefore, the concept of sound power level has been chosen for expressing the noise emission of appliances for household and similar purposes.
The preferred noise emission quantity is the A-weighted sound power level, LWA, in decibels (ref. 1 pW).
According to this part, two principal methods exist, the direct method and the comparison method, as described in 4.2 and 4.3 below. These two methods can be used alternatively.
Different types of environments, as described in 4.4, may be used. The special requirements may, if necessary, include one or several combinations among those available.
4.2 Direct method
The direct method can be used only for measurements in qualified test environments according to GB/T 3767-1991 for free field conditions over reflecting plane(s), and according to GB/T 6881.3-2002 for special reverberation test rooms.
With this method, the sound power level is determined
——in free field conditions over reflecting plane(s), from time-averaged sound pressure levels (on a mean-square basis) over the measurement surface and from the area of the measurement surface;
——in special reverberation test rooms, from averaged sound pressure levels, and from the reverberation time and the volume of the test room.
This method yields results expressed in A-weighted sound power levels (and in octave-band sound power levels, if required) which are calculated directly from measured sound pressure levels.
Note: This method can also be used in conjunction with more precise methods, as for instance as given in GB/T 6881.1-2002 and GB/T 6882-2008.
Contents of GB/T 4214.1-2017
Foreword i
Introduction iv
1 Scope and object
1.1 Scope
1.2 Object
1.3 Measurement uncertainty
2 Normative References
3 Terms and definitions
4 Measurement methods and acoustical environments
4.1 General
4.2 Direct method
4.3 Comparison method
4.4 Acoustical environments
5 Measuring instruments
5.1 Measuring instruments
5.2 instrument of measuring environment condition
5.3 Measuring instrument for operating condition
6 Operation and positioning of tested appliance
6.1 Assembly and preprocessing of appliance
6.2 Supply of electric energy and of water or gas
6.3 Climatic conditions
6.4 Loading and operating of appliances during tests
6.5 Location and mounting of appliances
7 Measurement of sound pressure levels
7.1 Microphone array, measurement surface and RSS location for essentially free field conditions over reflecting plane(s)
7.2 Microphone array and RSS location in hard-walled test rooms
7.3 Microphone array and reference sound source (RSS) location in special reverberation test rooms
7.4 Measurement
8 Calculation of sound pressure and sound power levels
8.1 General requirements
8.2 Corrections for background noise levels
8.3 Corrections for the test environment
8.4 Calculation of sound pressure level averaged over all measuring points
8.5 Calculation of sound power levels with the comparison method
8.6 Calculation of sound power levels in essentially free field conditions over a reflecting plane
8.7 Calculation of A-weighted sound power level with the direct method in special reverberation test rooms
9 Information to be recorded
9.1 General data
9.2 Description of appliance under test
9.3 Measurement method
9.4 Acoustical test environment
9.5 Instrumentation
9.6 Assembly and pretreatment of appliance under test
9.7 Power supply, water supply, etc.
9.8 Environmental conditions
9.9 Operation of the appliance under test
9.10 Location and mounting of the appliance under test
9.11 Measuring point locations
9.12 Measurement data
9.13 Calculated values of sound pressure and sound power levels
10 Information to be reported
10.1 General data
10.2 Appliances under test
10.3 Test conditions for appliances
10.4 Acoustical data
Annex A (Normative) Standard test table
Annex B (Normative) Test enclosure
Bibliography
