Acoustics—Measurement of sound insulation in buildings and of building elements—Part 7:Field measurements of impact sound insulation of floors
Some standard content:
105 91.120.30
National Standard of the People's Republic of China
GB/T 19889.7—2005/ISO 140-7:1998 Acoustics-Measurement of sound insulation in buildings and of building clementsPart 7:Field measurements of impact sound insulation of floors(ISO 140-7:1998,IY)
Published on 2005-07-29
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China Administration of Standardization of the People's Republic of China
Implementation on 2006-04-01
GB/T 19889.7--2005/ISO 140-7:1998 140-7:1998 Specification Textual nature of the specification Definition of terms Test equipment Test method and design 5.2 Generation of sound pressure at the site 5.5 Measurement of the sound pressure drop 5.4 Reduction diagram 5.5. False ringing time measurement and estimation of equivalent sound absorption 5.6 Noise control results Expression of results Test report Record (Standard Lu Yong) Requirements for non-impact noise t||Can be calculated B (regulatory appendix)
.General
Caution
Measurement of sound level
Measurement of the rescue rate
Wu Xincheng measurement method
H4 sound measurement and equivalent absorption estimation
0.5 back annual production
Create the characteristic penetration
Result expression
Attached (material attached) frequency band is
ci common series
center, 2 is small same distance
3 sound easy sampling
.1 average but the level and the interval
5 Micro-echo time...
Appendix D (informative appendix) Expression of results
Text overview
1/T19HM9 Standard for the measurement of buildings and building components, Part 1: Specification for laboratory tests of buildings Part 2: Verification and application of data Part 3: Experimental measurement of air insulation for building components Part 1: Field observation of room air insulation Part 5: Field measurement of ambient sound insulation and ambient air noise Part 3: Field measurement of sound insulation Part 4: Field measurement of sound insulation for panels CB/T 19889./—2005/[50 140-7:1998 Part 3, Laboratory measurement of sound quality of floor slabs: This part is part 7 of 19889, and is adopted in part 1407:169% of the city science and technology. This part sets the requirements for national standards and makes some revisions to 40-7:18: Measurement of the quality of the floor slabs and the quality of the materials used in the construction and injection molding of the components. This part is prepared by the Chinese Academy of Sciences.
This part is the International Chemical Association (SAC1.
Standard unit: Southeast University, Nanjing University. Economics and Management Department: Liu Xiaoyi, Meiqi University, Xinjian West and Qiong, Ministry of Education. Scope
CB/T19883.7--2005/1S0140-7:1998 Acoustics - Measurement of sound insulation of buildings and building components
Part 1: Field measurement of impact sound insulation of floor slabs. This part of GT19 stipulates the method of widely used impact sound insulation of building materials: The method of testing the sound insulation of wooden buildings with light recovery is suitable for the building with rats and the connection version. The measurement results can be compared with the replacement version under the market. Lu two sound medical energy, the performance of the user fat sound the most and the established contract requirements are compared. Energy board stealing production market implementation plan is 2: the quality of the machine to accept the review needs to be read carefully after the production of the modified fee after the implementation of the long professional technology: Ding 19.8 of the current provisions of 2 normative reference documents || tt || the following documents through (H/T "08 of the wood part of the reference to become the wood Hao section of the terms, but is the reference document of the note period, all the accompanying single excluding the foot talk or the order version are not applicable to this part: however. The effect of the wood part of the step you this research can be enough to inform you of the new version of this document, all the unpopular currency documents: the new version applies to this part || tt || stop process stimulation training correction wave device || tt | |G3/T57851983 Electroacoustic properties and test methods of sound-absorbing instruments G151734 Noise-absorbing instrument: 0542: 3)
G17183 Average sound absorption meter: 831985
G[3/T[S989.22005% Dizhuli screening medicine parts with sound measurement to the second part: Determination of number potential density, test state. He Pangyong 2
T3 Ding 1R93.325 Municipal Science and Technology General Building and Fast Building Average Bamboo Lu Gang Measurement Part 1: Laboratory Measurement of Airborne Sound of Building Parts (150110:: 1905)
JSO351:1SA: Sixth Science
Concrete teacher case sound absorption measurement
(T/T5221— 2M5 Building decoration price standard
3 Terms and definitions
The original language and regulations are used in the part
bao average sound level averagesnndpressnreleelnrm
The average of the space pressure when the market is close to the base pressure (P) level is the ratio of the average bottom to the average of the space. If there is a clear shadow of the product area (such as the area measured by the measurement station, the indoor average sound level is actually the measured star pressure level 1, at this time (1> r.—10lg
The pressure effect of different measuring points in the study can be determined by the work, Inh
GB/T 19889.7—2005/1S0 140-7:1993. 2
Improved impact sound pressure level impaclspundpwemurelevelL.
When the new test model is stimulated by the standard impactor, the 1/3 multiple of the receiving sound pressure level is expressed as B. 3. 3
Standardized impact sound pressure level nai'malixedipactprsurelevel global sound pressure frequency L plus correction term. The correction term is equal to the sound absorption A before the measurement and the receiving sound absorption A. The ratio of the two can be expressed by multiplying 10 by 1℃, and the effective formula is (the solution is A
F., = J., iiz
standardized impact sound pressure levelstandardized impact sunndpressurelevelL
（2）
body impact sound pressure level, to correct. You are learning to wait for the cloud receiving prison to measure the retreat time and the standard response time. The result is 1 with the base of the difference multiplied by 10, expressed in H. Calculation formula: Lr= L.-2Ole T
Note 1, T. =9. 5 s,
（3）
Let the sound output rate be standardized and standardized. The time is 5: the time of hunger response is almost considered. The volume is changed without sound.
Note: The time is limited. The standard is about 5. The level of production is effective for the year 4: 32V. The percussion instrument is designed. The head is: A is the state and blood limit, rn is the connection and release, etc. rn3.5
The percussion sound pressure level is improved. The retluxtion af [mpar.t snn ucl pressure levelat.
The average sound level difference in the receiving room before and after the board surface layer (such as the ground) is expressed in terms of 7.1. For more information, please refer to GB/T159.H
4 Test equipment
The test equipment shall be in accordance with the requirements of the draft.
Standard sound level measurement equipment shall comply with the requirements of 0 or 1 level specified in GB/T78-1993 and GB/T7181-1997. Requirements. For example, the whole system including the sound transmission end shall be calibrated before each operation using the Class 1 calibration system in accordance with GB/324-18-34. For the level meter used for plane field measurement, the diffusion field shall be calibrated. The wave measurement equipment shall comply with the requirements of GB/324-18-8. The test method and calculation method of the strong response shall be in accordance with the requirements of GB/324-18-8.1 General
If the quantity to be measured is not agreed upon in advance, the sound source for the on-site measurement shall be 1/3 times the source. The single-value evaluation quantity converted from the measurement result of CB/T19889.7-2005/TSO 140-7,199B shall not be directly compared with the result of the installation conversion. The measurement method of the multiple process shall comply with the provisions of the appendix.
5.2 Generation of sound field
The sound field should be generated by the impact. See Section 4. The impactors should be randomly distributed and placed at least 10 different positions on the test floor. The distance between the impactor position and the floor mark should be not less than 1.5m. For anisotropic floor structures with or without bridging, more positions may be required. The connecting line of a row of wires should be at an angle of 45 degrees to the direction of the wire. The sound level of the device when it starts to be pulled out can show the change of the chain. In this case, the measurement should be started after the level is stable. If the stability condition is still not determined after the start of the shock, the time period that meets the requirements should be selected to measure the reverse measurement, and the time period should be selected. When measuring the building with soft surface layer, the standard of the device should comply with the provisions of Appendix A. Appendix A also gives the precautions for the use of the device in the building.
5.3 Sound pressure level of the device
5.3. 1 General rule: A single microphone can be used to measure the sound pressure at the same position in the room. A fixed microphone array can be formed into a moving microphone array. The sound level trace obtained at each data position can be averaged over all the microphone positions. 5.3.2 Data position: The following minimum spacing must be met: - The distance between one or two microphones and the room boundary or amplifier is 1.5m - The distance between the microphone and the control core is 1.5m. Note: It is possible to take a larger angle,
Fixed microphone positions:
There should be at least four microphone positions and they should be evenly distributed within the allowable range of the performance room. Moving microphone positions
When movable microphones are used, the scanning radius should be at least 9.?m. The moving plane should be inclined so as to maximize the available space for measurement. The distance between the moving plane and the room surface, floor, ceiling should not be less than 10, and the scanning radius should not be less than 1=95.3.3 Measurement
Fixed microphone positions:
Use Sichuan For a given transmitter position, at least six times, at least a microphone position and at least a small impactor position should be selected. For example: a transmitter and a small impactor are used to measure the four transmitters, and two transmitters and two impactors are used to measure the quality of the transmitter. The mobile transmitter is used to measure at least times, that is, one impactor position is measured once. When using a large or a small impactor position, one or a mobile transmitter position can be used to measure as much as possible. 5.3.4 Average time of average value|| tt||In the microphone position, for the heart rate measurement lower than the heart rate H: the average reading time of each band is at least 6. For the high frequency single market, the average time is short, not less than 1, use the mobile microphone, and the time required to cover the whole sweep is not less than 3C. In order to avoid the blood change caused by long-term collision, the mobile microphone is also used in the full wave state for real-time measurement.
5.4 Measurement and frequency range
Product pressure level should use 1/3 frequency range, the frequency should be less than the center rate, the unit is H: CB/T 19889.7—2005/180 14C-/:1998200
In order to compare the results of laboratory measurements conducted by the five-year early opening/T5G station, the measurement range is not large enough to be below 1/3 times the center frequency of the test, the unit is H: AcCS
If more information is needed for low-frequency ranges, the center frequency is below "times": The unit is H: C53
Guidelines for the average measurement of such low-frequency problems are given in the record. 5.5 , Reverberation time measurement and equivalent absorption estimation In formula (2), the equivalent sound absorption is corrected according to 1S351:1SH5. The reverberation time in the receiving room is measured and the Sabine formula is used for estimation (estimation period: 1
A—absorption, unit is square meter (m))
The receiving room unit is cubic meter ():
1—error time, unit is banknote (3)
According to IS) 354:1935, the sound source stops emitting sound approximately 91 seconds later 1. Calculate the response time with the decay curve, or calculate it on the decay curve by a few decibels lower than the start of the decay. The high decay curve should not be too low, and the decay should not be too large. The selected decay curve should be at least 10 dB high. For each frequency band, measure at least six times. For each case, use at least three microphone positions, and each measuring point needs to have a reading number to ensure compliance. The mobile noise detector required by 5.3.2 shall meet the requirements, but its judgment time shall not be less than S09. 5. Noise indication signal
to ensure that the receiving system is in the correct condition. The influence of external noise such as high noise level outside the receiving room is prohibited. In order to check the electrical operation of the receiving system, only the transmitter head (equivalent to the transmitter head) shall be used instead of the transmitter head. Note: The air dryness generated by the transmitter and transmitted to the receiving room cannot affect the receiving sound level. The sound level should be at least lower than the total level of the signal and the normal level. The sound level correction shall be calculated as 5% if the pressure difference is less than ten.
1olgio..w
Where:
——The signal level, in decibels Leb
The signal type is not a single sound, the highest sound number of the four, single tube (this); single level ()
Any sound level and less than or equal to 6, then the correction value of B shall be used, B shall be stopped, at this time, the measurement report shall clearly indicate 1, and the limit of correction shall be carefully measured (see Section 1). 6 Precision
The measurement method shall have the characteristics of shifting weight, and shall be determined and frequently tested according to the method specified in GB/T1988\.2-2CU5: When the measuring length is changed, the fast-release device shall be equipped with a delay according to the emergency,? The result of the impact sound pressure level between the two objects should be calculated from all the standard parameters: or the standardized impact sound pressure level should be corrected to the decimal point and given in the form of tables and curves. The period in the test report should show the relationship between the pressure level in d value and the logarithmic scale, using the following size, -5mr. Table 11 is not a correct choice!
GR/T:9889,7-2005/180140-7:1938 uses the table form of the appendix D. This concise form of the test report lists all the details about the design object, measurement method and measurement results.
The half section is calculated according to the value of the three/3 pieces of the process of the octave (or 1) (but when the effect should be used formula 6) (7), indB
= 0 (
I.... lu'gDiu'.au dB
If the violation of the test pad, the arithmetic mean value of the new bottle with the new control sum should be calculated: 8 Test report
The test report should contain the following:
Heat [3/T15289 this part)
Test unit:
Name and address of the commission or individual;
Test period
Description of the construction and test installation;
According to the actual volume
........, 7
Standardized control sound level, or standardized single pressure level L, with the change of frequency, select a special day; hi
Brief description of point measurement method and instrument
When the internal sound (acoustic or electrical, respectively) makes the sound of a period of time cannot be effectively demarcated, the version should be given in the form of 1 or...dB. If the lateral transmission is measured, the result is expressed in the form of 1, and the lateral transmission sound measurement range is clearly stated. Which parts will be produced:||tt ||According to the sales. Or) also make a single evaluation opinion G3/T0121. And clearly explain the results of the single evaluation order number H for the current garbage test,
CB/119889,7-2005/1S0140-7,1998, etc. should be compiled in accordance with the requirements of Chapter bzxZ.net
Appendix A
(current normative record.
Requirements for standard implants
The whole device must have five lithiums and be arranged in a straight line or above: the distance between the adjacent chain ten centers is (100-3)mr:The distance between the center of the tongue-dropping device and the center line of the adjacent pin should not be less than 13\ or the foot should be equipped with a collapse resistance. The impact force of each person leaving the building is the effective quality of the self-return impact, and the allowable deviation of the impact force is ± 5%. In order to control the lifting force against the obstacle, not only the height of the chain should be guaranteed, but also the accuracy of the hammer control should be within the range: the weight of the hammer is (500112>, then the impact speed should be (3.5550.022)m/s. If it can be guaranteed to be within (5), the control speed can be corrected by +0.033/s: be careful of the verticality between the falling parties, test the floor surface, and the error is within the range. The book has a hammer that is about (0.2)m.\The control surface of the hammer is made of hard material and has a curvature of 0c-00)mm. This can be tested by the following method:) Use at least two measuring lines that intersect the center point of the impact to pull the impact back. Carry out the measurement, if the measurement result is within the specified range of wear, the electrical rate of the special control surface shall meet the requirements, A.1 The radius of both ends is 500mm, the distance between the two industries is 400 and 00mF, the average measurement value is within the normal wear limit, 01, SH
high center creation energy height/mm
design: make the head curvature not exceed the minimum capacity function and the corresponding degree of pressure can be selected, Figure A, 1 The tolerance limit of the curvature of the chain head
6 The curvature of the head is measured by the ball diameter meter at three points with a diameter of 20m. The average time between the two impactors should be (Qinm, the continuous labor time is 1020)ms.
The time of the pull does not exceed 3.
When using the standard impactor to measure the extension of a soft surface or an uneven surface, ensure that the impactor falls at least 200 meters below the support plane. All inspections of the standard impactor should be carried out on a flat surface so that the impactor can be used on any test surface.
C8/119889.7—2005/15 140-/,1998If the test surface is covered with a soft layer or the surface is not flat, so that the required 40m is not reached, that is, the lower belt cannot reach the plane, a cushion layer can be laid on the surface to ensure the accurate 40TLTT drop height. The impact end should be calibrated under the standard test door to see if it meets all the requirements. When the sag reaches 1.1mIr and the horizontal inclination reaches a maximum, the parameters of the impactor that has not been activated need to be calibrated for several times, including the distance between the hammer and the impact head, the impact head diameter, the measurement of the hammer (except for the repaired offset head), the time between the tongue and the lifting, and the maximum possible drop height. The connection, head diameter and rate, drop direction and time between impacts should be calibrated regularly. The technical accuracy of the approved measurement shall not exceed 20% of the value of the test piece. G/T 19889.7-2335/[5 140-7:1998 B.1 Method for measuring sound insulation in octave bands This part is applicable to the following methods: 3 Method for estimating the sound insulation performance between two small rooms on site. If short-range measurements are required, an appropriate method should be used. B.2 Method for measuring the rated voltage of the sound source The method for calculating the average time of the half-average sound insulation shall be consistent with the method for calculating the average time of the half-average sound insulation.
.3 The frequency range of the special measurement
The production pressure is certified to use at least the following center frequency times the heat of my combustion method, unit is z: 125205c010002600
I will give more information and compare it with the R/1883.12 to the actual salt medicine result, and expand its frequency range back to the center frequency times of 3Tz. If the same range is required, use a flowmeter with a center frequency of 63: When the low-frequency measurement is required, follow the recorded guidelines: B.4 Reverberation time measurement and equivalent absorption time calculation 5.5 ship determination, treatment through,
3.5 back barrier sound correction
5, 5 The method is completed.
R.6 Precision of the measurement
The requirements specified in clause 5 shall be followed:
B.7 Expression of results
Test report for the test of the impact noise level: All measured values of the normalized impact noise level shall be expressed in the first decimal place and presented in a table. The diagram in the test report shall show the frequency in units of minutes and the logarithmic scale. Dimensions: 1 m. Weight:
If repeated measurements are made, the average value of the results of the measurement stations in each frequency band shall be calculated. 3
c.1 General
(Informative annex!
Guidelines for low frequency measurement
CB/T:19883.7—2005/ISO 140-7:1998 to test the room, especially when the room is older, in the low efficiency range (usually refers to less than 40H to maintain the special requirements of 1100H without protection of the sound, etc.), the quality of the room size is less than one wavelength of the service requirements in the micro-design can not meet the requirements. In the low frequency band room aid number less than the entire room space! Produce and install the permanent inside. In order to minimize the measurement of the sound accuracy. The sound in the recording room needs to be sampled and the distance should be satisfied. Special requirements should be made more efforts: small volume room and people are not suitable for the room. The larger the measurement layer, the better the result. At least one dimension of the room is the wavelength of the center of the lowest frequency band, and the other dimension is half the wavelength of the center of the lowest frequency band. The room must have enough space to place the microphones as required:
.2 Minimum spacing
Within 1/4 wavelength of the room boundary, the sound will increase. The test chain has a reduced test rate, the city gate (historical.. virtual treatment, high intelligence doubled when measuring high frequency, the minimum distance between each speaker position and the room boundary is 1, 2
C.3 Sound sampling
In order to obtain a standard size in the room, the microphones should be evenly distributed in the room. If dynamic transmission is used, the sound should be sampled in the entire space as much as possible. For rooms with room sizes close to halfway, the sound level obtained in the middle of the room is very reliable. In addition to the strict wind direction, the average time of the average value is 4 times the filtering level of the program. The lossy mode is less, for the Hz band reading, the actual average time and the actual increase in the average signal are quite large (6 times the tester's time to find the second signal), when using a dynamic microphone, the average time to read the average signal should not be less than 62$:
.5 visual response time
In the very low frequency range, the surface of the test room has a longer time. To avoid this situation, the design of the distributed indoor sound absorption mode overlaps the improvement, reducing the interference of the single room mode on the brightness.
The blood pressure of the child is not exceeded 3.
When the impactor is used to measure the soft surface or uneven surface, the sound is guaranteed to make the child fall below the support plane of the impactor at least Amn
All the inspections of the impactor should be carried out on the flat surface so that the impactor can be used on any test surface.
C8/119889.7—2005/15 140-/,1998If the test surface is covered with a soft layer or the surface is not flat, so that the required 40m is not reached, that is, the lower belt cannot reach the plane, a cushion layer can be laid on the surface to ensure the accurate 40TLTT drop height. The impact end should be calibrated under the standard test door to see if it meets all the requirements. When the sag reaches 1.1mIr and the horizontal inclination reaches a maximum, the parameters of the impactor that has not been activated need to be calibrated for several times, including the distance between the hammer and the impact head, the impact head diameter, the measurement of the hammer (except for the repaired offset head), the time between the tongue and the lifting, and the maximum possible drop height. The connection, head diameter and rate, drop direction and time between impacts should be calibrated regularly. The technical accuracy of the approved measurement shall not exceed 20% of the value of the test piece. G/T 19889.7-2335/[5 140-7:1998 B.1 Method for measuring sound insulation in octave bands This part is applicable to the following methods: 3 Method for estimating the sound insulation performance between two small rooms on site. If short-range measurements are required, an appropriate method should be used. B.2 Method for measuring the rated voltage of the sound source The method for calculating the average time of the half-average sound insulation shall be consistent with the method for calculating the average time of the half-average sound insulation.
.3 The frequency range of the special measurement
The production pressure is certified to use at least the following center frequency times the heat of my combustion method, unit is z: 125205c010002600
I will give more information and compare it with the R/1883.12 to the actual salt medicine result, and expand its frequency range back to the center frequency times of 3Tz. If the same range is required, use a flowmeter with a center frequency of 63: When the low-frequency measurement is required, follow the recorded guidelines: B.4 Reverberation time measurement and equivalent absorption time calculation 5.5 ship determination, treatment through,
3.5 back barrier sound correction
5, 5 The method is completed.
R.6 Precision of the measurement
The requirements specified in clause 5 shall be followed:
B.7 Expression of results
Test report for the test of the impact noise level: All measured values of the normalized impact noise level shall be expressed in the first decimal place and presented in a table. The diagram in the test report shall show the frequency in units of minutes and the logarithmic scale. Dimensions: 1 m. Weight:
If repeated measurements are made, the average value of the results of the measurement stations in each frequency band shall be calculated. 3
c.1 General
(Informative annex!
Guidelines for low frequency measurement
CB/T:19883.7—2005/ISO 140-7:1998 to test the room, especially when the room is older, in the low efficiency range (usually refers to less than 40H to maintain the special requirements of 1100H without protection of the sound, etc.), the quality of the room size is less than one wavelength of the service requirements in the micro-design can not meet the requirements. In the low frequency band room aid number less than the entire room space! Produce and install the permanent inside. In order to minimize the measurement of the sound accuracy. The sound in the recording room needs to be sampled and the distance should be satisfied. Special requirements should be made more efforts: small volume room and people are not suitable for the room. The larger the measurement layer, the better the result. At least one dimension of the room is the wavelength of the center of the lowest frequency band, and the other dimension is half the wavelength of the center of the lowest frequency band. The room must have enough space to place the microphones as required:
.2 Minimum spacing
Within 1/4 wavelength of the room boundary, the sound will increase. The test chain has a reduced test rate, the city gate (historical.. virtual treatment, high intelligence doubled when measuring high frequency, the minimum distance between each speaker position and the room boundary is 1, 2
C.3 Sound sampling
In order to obtain a standard size in the room, the microphones should be evenly distributed in the room. If dynamic transmission is used, the sound should be sampled in the entire space as much as possible. For rooms with room sizes close to halfway, the sound level obtained in the middle of the room is very reliable. In addition to the strict wind direction, the average time of the average value is 4 times the filtering level of the program. The lossy mode is less, for the Hz band reading, the actual average time and the actual increase in the time required to take the average signal are quite large (6 times the tester's time to obtain the second signal). When using a dynamic microphone, the average time to read the average signal should not be less than 62$:
.5 visual response time
In the very low frequency range, the surface of the test room has a longer time. To avoid this situation, the design of the distributed indoor sound absorption mode overlaps the improvement, reducing the interference of the single room mode on the brightness.
The blood pressure of the child is not exceeded 3.
When the impactor is used to measure the soft surface or uneven surface, the sound is guaranteed to make the child fall below the support plane of the impactor at least Amn
All the inspections of the impactor should be carried out on the flat surface so that the impactor can be used on any test surface.
C8/119889.7—2005/15 140-/,1998If the test surface is covered with a soft layer or the surface is not flat, so that the required 40m is not reached, that is, the lower belt cannot reach the plane, a cushion layer can be laid on the surface to ensure the accurate 40TLTT drop height. The impact end should be calibrated under the standard test door to see if it meets all the requirements. When the sag reaches 1.1mIr and the horizontal inclination reaches a maximum, the parameters of the impactor that has not been activated need to be calibrated for several times, including the distance between the hammer and the impact head, the impact head diameter, the measurement of the hammer (except for the repaired offset head), the time between the tongue and the lifting, and the maximum possible drop height. The connection, head diameter and rate, drop direction and time between impacts should be calibrated regularly. The technical accuracy of the approved measurement shall not exceed 20% of the value of the test piece. G/T 19889.7-2335/[5 140-7:1998 B.1 Method for measuring sound insulation in octave bands This part is applicable to the following methods: 3 Method for estimating the sound insulation performance between two small rooms on site. If short-range measurements are required, an appropriate method should be used. B.2 Method for measuring the rated voltage of the sound source The method for calculating the average time of the half-average sound insulation shall be consistent with the method for calculating the average time of the half-average sound insulation.
.3 The frequency range of the special measurement
The production pressure is certified to use at least the following center frequency times the heat of my combustion method, unit is z: 125205c010002600
I will give more information and compare it with the R/1883.12 to the actual salt medicine result, and expand its frequency range back to the center frequency times of 3Tz. If the same range is required, use a flowmeter with a center frequency of 63: When the low-frequency measurement is required, follow the recorded guidelines: B.4 Reverberation time measurement and equivalent absorption time calculation 5.5 ship determination, treatment through,
3.5 back barrier sound correction
5, 5 The method is completed.
R.6 Precision of the measurement
The requirements specified in clause 5 shall be followed:
B.7 Expression of results
Test report for the test of the impact noise level: All measured values of the normalized impact noise level shall be expressed in the first decimal place and presented in a table. The diagram in the test report shall show the frequency in units of minutes and the logarithmic scale. Dimensions: 1 m. Weight:
If repeated measurements are made, the average value of the results of the measurement stations in each frequency band shall be calculated. 3
c.1 General
(Informative annex!
Guidelines for low frequency measurement
CB/T:19883.7—2005/ISO 140-7:1998 to test the room, especially when the room is older, in the low efficiency range (usually refers to less than 40H to maintain the special requirements of 1100H without protection of the sound, etc.), the quality of the room size is less than one wavelength of the service requirements in the micro-design can not meet the requirements. In the low frequency band room aid number less than the entire room space! Produce and install the permanent inside. In order to minimize the measurement of the sound accuracy. The sound in the recording room needs to be sampled and the distance should be satisfied. Special requirements should be made more efforts: small volume room and people are not suitable for the room. The larger the measurement layer, the better the result. At least one dimension of the room is the wavelength of the center of the lowest frequency band, and the other dimension is half the wavelength of the center of the lowest frequency band. The room must have enough space to place the microphones as required:
.2 Minimum spacing
Within 1/4 wavelength of the room boundary, the sound will increase. The test chain has a reduced test rate, the city gate (historical.. virtual treatment, high intelligence doubled when measuring high frequency, the minimum distance between each speaker position and the room boundary is 1, 2
C.3 Sound sampling
In order to obtain a standard size in the room, the microphones should be evenly distributed in the room. If dynamic transmission is used, the sound should be sampled in the entire space as much as possible. For rooms with room sizes close to halfway, the sound level obtained in the middle of the room is very reliable. In addition to the strict wind direction, the average time of the average value is 4 times the filtering level of the program. The lossy mode is less, for the Hz band reading, the actual average time and the actual increase in the average signal are quite large (6 times the tester's time to find the second signal), when using a dynamic microphone, the average time to read the average signal should not be less than 62$:
.5 visual response time
In the very low frequency range, the surface of the test room has a longer time. To avoid this situation, the design of the distributed indoor sound absorption mode overlaps the improvement, reducing the interference of the single room mode on the brightness.The sound in the recording room needs to be sampled and the distance should meet certain special requirements: small rooms and rooms with inappropriate space. A larger frequency measurement layer can always reduce the results. At least one dimension of the room is the wavelength of the center of the low-frequency band, and the other dimension is half the wavelength of the center of the lowest frequency band. The room must have enough space to place the microphones as required:
.2 Minimum spacing
Within 4 wavelengths of the room boundary, the sound will increase. The test rate is reduced, the city door (historical.. virtual treatment, high intelligence is doubled when measuring frequency, the minimum distance between each speaker position and the room boundary is 1, 2
C.3 Sound sampling
In order to obtain a standard size in the room, the microphones should be evenly distributed in the room. If dynamic transmission is used, the sound should be sampled in the entire space as much as possible. For rooms with room sizes close to halfway, the sound level obtained in the middle of the room is very reliable. In addition to the strict wind direction, the average time of the average value is 4 times the filtering level of the program. The lossy mode is less, for the Hz band reading, the actual average time and the actual increase in the average signal are quite large (6 times the tester's time to find the second signal), when using a dynamic microphone, the average time to read the average signal should not be less than 62$:
.5 visual response time
In the very low frequency range, the surface of the test room has a longer time. To avoid this situation, the design of the distributed indoor sound absorption mode overlaps the improvement, reducing the interference of the single room mode on the brightness.The sound in the recording room needs to be sampled and the distance should meet certain special requirements: small rooms and rooms with inappropriate space. A larger frequency measurement layer can always reduce the results. At least one dimension of the room is the wavelength of the center of the low-frequency band, and the other dimension is half the wavelength of the center of the lowest frequency band. The room must have enough space to place the microphones as required:
.2 Minimum spacing
Within 4 wavelengths of the room boundary, the sound will increase. The test rate is reduced, the city door (historical.. virtual treatment, high intelligence is doubled when measuring frequency, the minimum distance between each speaker position and the room boundary is 1, 2
C.3 Sound sampling
In order to obtain a standard size in the room, the microphones should be evenly distributed in the room. If dynamic transmission is used, the sound should be sampled in the entire space as much as possible. For rooms with room sizes close to halfway, the sound level obtained in the middle of the room is very reliable. In addition to the strict wind direction, the average time of the average value is 4 times the filtering level of the program. The lossy mode is less, for the Hz band reading, the actual average time and the actual increase in the average signal are quite large (6 times the tester's time to find the second signal), when using a dynamic microphone, the average time to read the average signal should not be less than 62$:
.5 visual response time
In the very low frequency range, the surface of the test room has a longer time. To avoid this situation, the design of the distributed indoor sound absorption mode overlaps the improvement, reducing the interference of the single room mode on the brightness.
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