Acoustics - Guidelines for the measurement and assessment of exposure to noise in a working environment
Introduction to standards:
This standard describes the determination of acoustic quantities, in particular the type and location of sound pressure level measurements to be made, the time sampling and frequency analysis required, and the special characteristics of the noise being measured that should be considered. GB/T 21230-2007 Guidelines for the measurement and evaluation of noise exposure in acoustic working environments GB/T21230-2007 Standard download decompression password: www.bzxz.net
This standard describes the determination of acoustic quantities, in particular the type and location of sound pressure level measurements to be made, the time sampling and frequency analysis required, and the special characteristics of the noise being measured that should be considered.
This standard is equivalent to ISO9612:1997 "Guidelines for the measurement and evaluation of noise exposure in acoustic working environments" (English version).
Appendices A, B, C and D of this standard are all informative appendices.
This standard is proposed by the Chinese Academy of Sciences.
This standard is under the jurisdiction of the National Technical Committee for Acoustic Standardization (SAC/TC17).
The drafting organizations of this standard are: Institute of Acoustics, Chinese Academy of Sciences, Zhejiang University, Nanjing University, Shenzhen Zhongya Electromechanical Industry Co., Ltd.
The main drafters of this standard are: Cheng Mingkun, Tian Jing, Zhang Bangjun, Zhai Guoqing, Qiu Xiaojun, Fang Qingchuan.
The clauses in the following documents become the clauses of this standard through reference in this standard. For all dated referenced documents, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, the parties who reach an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For all undated referenced documents, the latest versions are applicable to this standard.
GB/T3222.1 Acoustics - Description, measurement and evaluation of environmental noise - Part 1: Basic parameters and evaluation methods (GB/T3222.1-2006, ISO1996-1:2003, IDT)
GB/T3240 Frequencies commonly used in acoustic measurements (GB/T3240-1982, neqISO266:1975)
GB/T3241 Octave and fractional octave filters (GB/T3241-1998, eqvIEC1260:1995)
GB/T3947-1996 Acoustics - Terminology
GB/T7584.1 Acoustics - Hearing protectors - Part 1: Subjective method for measuring sound attenuation (GB/T 7584.1-2004, ISO4869-1:1990, IDT)
GB/T7584.2 Acoustics Hearing protectors Part 2: Estimation of A-weighted sound pressure level effective when wearing hearing protectors (GB/T7584.2-1999, idtISO4869-2:1994)
GB/T14366 Acoustics Measurement of occupational noise and evaluation of noise-induced hearing loss (GB/T14366-1993, eqvISO1999:1990)
GB/T15952 Technical requirements for personal sound exposure meters (GB/T15952-1995, idtIEC61252:1993)
GB/T17248.2 Acoustics Noise emitted by machines and equipment - Measurement of emission sound pressure levels at work and other specified locations - Engineering method for approximating free field above a reflecting surface (GB/T17248.2-1999, eqvISO11201:1995)
ISO532:1975 Calculation of acoustic loudness level
ISO/TR3352:1974 Evaluation of the effect of acoustic noise on speech intelligibility
ISO3891:1978 Acoustics - Method for describing ground-audible aircraft noise
ISO/TR4870:1991 Acoustics - Apparatus and calibration for speech intelligibility tests
ISO7196:1995 Frequency weighting characteristics for acoustic infrasound measurements
ISO7731:1986 Acoustics - Hazard signals in the workplace - Audible hazard signals
Some standard content:
ICS17.140
National Standard of the People's Republic of China
GB/T21230-2007/ISO9612:1997
Acoustics--Guidelines for the measurement and assessment of exposureto noise in a working environment(ISO 9612:1997.IDT)
Published on November 14, 2007
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of China
Numerical protection
Implementation on May 1, 2008
Normative references
Quantities and definitions
Noise measurement in the working environment
Measuring instruments
Spectrum analysis
Infrasound and ultrasound
Special noise characteristics
Application of measurement results
Influence on labor and protection
Influence on language communication.
Infrasound and ultrasound||t t||Appendix A (Informative Appendix) Other effects of noise
GB/T21230--2007/1S09612:199711
Appendix B (Informative Appendix)
Example of calculating the equivalent continuous A-weighted sound pressure level using the formula in 4.3.4... Appendix (Informative Appendix) Determination of the evaluated sound level Appendix D (Informative Appendix)
References
Noise measurement accuracy level
GB/T21230-2007/IS09612-1997
This standard is equivalent to 1S09612:1997% Guide for measurement and evaluation of noise exposure in acoustic working environments (English version). Appendix A, Appendix B, Appendix C and Appendix D of this standard are all informative appendices. This standard is proposed by the Chinese Academy of Sciences. This standard is under the jurisdiction of the National Technical Committee for Acoustics Standardization (SAC/TC17). The drafting units of this standard are: Institute of Acoustics, Chinese Academy of Sciences, Xinjiang University, Nanjing University, Shenzhen Zhongya Taodian Industrial Co., Ltd. The main drafters of this standard are Cheng Mingkun, Yong Jing, Zhang Bangjun, Zhai Guoqing, Qiu Xiaojun and Fang Qingchuan. GB/T21230-2007/1S09612:1997 Introduction
The unified measurement, analysis and evaluation of noise in the workplace is very important for evaluating the potential impact of noise on the health, comfort, safety and work efficiency of workers. Although there are standards for noise measurement in operator positions and specific facility environments and other standards that describe the impact of noise on specific human functions, in order to evaluate the impact of noise on workers, this standard still gives the "guidelines for what type of measurements should be made at what locations in order to monitor compliance with the corresponding noise standards and indicate whether control measures should be taken to reduce noise. CHINA
1 Scope
GB/T21230-2007/1S09612:1997 Guidelines for the measurement and evaluation of noise exposure in acoustic working environments
t||This standard addresses the determination of acoustic quantities, in particular the type and location of sound pressure level measurements to be made, the time sampling and frequency analysis required, and the special characteristics of the noise being measured that should be considered, in order to be able to evaluate the various effects of noise in the working environment on workers who are habitually exposed to this environment. This standard is intended for use by relevant management departments responsible for determining and monitoring compliance with noise limits in the workplace and deciding whether hearing protection programs and noise reduction measures can be implemented. The standard itself does not specify or recommend acceptable noise limits. Although the reference book includes references to statistical sampling methods, the standard does not specify statistical sampling methods for describing group noise exposure. The standard describes the application of measurement results with respect to noise effects on hearing, conversation interference and other noise effects. It also includes special requirements for describing infrasound and ultrasound exposure. Appendix Appendix A gives the application of the standard in terms of the impact of noise on health, work efficiency, comfort and the audibility of alarm signals. Appendix B gives an example of the calculation of the continuous equivalent A-weighted sound pressure level. Appendix C discusses the calculation of the evaluation sound level including pure tone and impulse noise corrections. Appendix D specifies the noise measurement accuracy level. 2 Normative references
The clauses in the following documents become clauses of this standard through reference in this standard. For any dated referenced documents, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, the parties to an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For any undated referenced documents, the latest versions apply to this standard. GB/T3222.1 Description, measurement and evaluation of acoustic environmental noise Part 1: Basic parameters and evaluation methods (GB/T3222.12006.ISO1996-1.2003, IDT) GB/T3240 Frequency band in acoustic measurement (GB/T32401982.ncqISO266:1975) GB/T3211 rated range and fractional range filters (GB/T32411998.egvIFC1260:1995) GB/T39471996 Acoustic terminology
GB/T7584.1 Acoustic hearing protectors: Part 1: Subjective method for measuring sound attenuation (GB/T7584.120041SO4869-1:1990.IDT)
GB/T7584.2 Acoustic hearing protectors Part 2: Estimation of effective A-weighted sound pressure level when wearing hearing aids (GB/T7584.2-1999, idt ISO 4869-2:1994)
GB/T14366 Acoustics - Measurement of occupational sound and evaluation of hearing loss caused by noise (GB/T143661993, eqVISO1999:19909
GB/T15958 Technical requirements for personal sound exposure meters (GB/T15952-1995.idtIEC61252:1993) GB/T17248.2 Acoustics - Measurement of sound pressure levels emitted by machines and equipment at operating positions and other designated positions - Engineering method for approximating free fields above a reflecting surface (GB/T17248.21999-VTSO11201:1995) ISO532:1975 Calculation of acoustic loudness levels
ISO/TR3352:1974 Evaluation of the effect of acoustic noise on speech intelligibility ISO3891:1 978 Acoustics Method of description of audible aircraft noise on the ground ISO/TR4870:1991 Acoustics Apparatus and calibration for speech intelligibility tests ISO7196:1995 Acoustics Characteristics of frequency meter weights for infrasound measurements ISO7731:1986 Acoustics Hazard signals in the workplace Audible hazard signals GB/T212302007/1 S09612:1997
1 S099211:1995 Acoustics Human ergonomic evaluation of speech conversation Part 1: Speech interference level and conversation distance of people with normal hearing in direct conversation (SIL method) IEC60042:2003 Electroacoustic sound calibrator
TEC61672-1:2002 Mains sound level meter Part 1: Specification 3 Quantities and definitions
This standard uses the following quantities. For their definitions, please refer to the relevant standards and they will not be repeated here. Quantity
Sound pressure level
Peak sound pressure level
A-weighted sound pressure level
C-weighted sound pressure level
People-weighted sound pressure level
Duration of
Cumulative percentage
Times of color band sound pressure level
1/3 times of sound pressure level
8-hour period
Normalized time period:
Time of continuous conduction of A-weighted sound pressure level Section
The workers are exposed tobZxz.net
beam noise on a daily basis Section
Duration for
Temporary sound level
Deep sound permanent map
Impulse noise
Evaluation sound level
Speech interference level
Loudness level
Hazardous noise level
Noise measurement in working environment
Quote Yan Yi's standard
GB/T 14366-1993,
CB/T39471996
67672-1
GB/T14355-1993,
GB2T3947
TEC6721
GB/T 1366
GB/T39z
195.18O9921-1
TEC61672
GB/T 3222.
GB/T3947
ISO532
GB/T14G6
GB/T3947| |tt||CB/T 3617-1995
GH/ 190522003
CB/T3222.12006
ISO 9921-1,GB/T 39471996
ISO/TR 3352
ISO 226.GB/T 39471996
IS013891.GB/T394T—1996
4.1 General
This chapter introduces the measurement methods of sound pressure levels in the workplace. The measurement methods include the use of measuring instruments (see 4.2) and microphone position, measurement period, individual noise quantities, especially the equivalent continuous A-weighted sound pressure level (see 4.3.4), the normalized equivalent continuous A-weighted sound positive level (see 4.3.5), The determination of daytime and nighttime sound exposure (see 4.3.6) and evaluation sound level (see 4.3.10 and Appendix C). Appendix D.1 gives the determination of GB/T 21230-2007/IS0 9612:1997 using sampling technology, etc. Effective continuous person-weighted sound pressure level and its method of measurement. In order to determine compliance with the specified noise limits and to evaluate the uncertainty of the measurement (see Appendix D.2), the comparison of the results with the limits (see Appendix D.3) and the contents of the measurement report (see Appendix D.4) are given in the catalog. See Appendix D.4 for guidance.
4.2 Measuring instruments
4.2.1 Sound level meter
The sound level meter should be at least Class 2 as specified in IEC61672-1:2002. The instrument requirements are: it is best to use a Class 1 sound level meter. The individual sound exposure meter is in accordance with GB/T15952. In order to measure whether the instrument's peak sound pressure is overloaded: it is best to use an instrument with an overload indicator.
Integral average The sound level meter shall at least comply with the Class 2 instrument specified in IEC61672-1:2002. 4.2.2 Octave band and 1/3 octave band filters The octave band and 1/3 octave band filters shall comply with the requirements of GB/T3241. The center frequency of the segment should comply with the requirements of GB/T3240.
4.2.3 Auxiliary measuring equipment
The sound level recorder for recording sound levels shall comply with the relevant provisions of [EC61672-1:2002, such as the requirements for time weighting. The statistical analyzer should comply with the time weighting F of IEC61672-1-2002. The selection of the level difference is related to the whole range of noise level, but should not be greater than dB. The tape recorder or other equipment for storing the fault signal should be at least The acoustic calibrator used for calibration and inspection of acoustic measuring instruments shall meet or exceed the technical indicators of Class 2 specified in IEC50942:2003. Calibration and Inspection
In order to comply with the requirements of IEC61672-1:2002 or GB/T15952, the calibrator should be calibrated regularly. The recommended calibration interval is no more than three years.
The user should at least perform an on-site check before and after each set of measurements. The amplifier, recorder and indicator should be electrically calibrated. The entire system including the microphone should also be acoustically calibrated (if a commercial calibration instrument is used). Acoustic calibration should be carried out on site as far as possible and the accuracy of the measurements must be determined (see Appendix D).
4.3 Measurements
4.3.1 General
Basic measurements The best quantities are equivalent continuous A-weighted sound pressure level (L) and A-weighted sound exposure over a given period of time T. Depending on the type of sound and the impact being assessed, it may be necessary to measure the peak sound pressure level. In some cases, it may be necessary to measure the audible sound, ultrasonic or infrasound bands and [ /3 octave band sound pressure level. If the ability to talk in a noisy environment is to be evaluated, then the Speech Interference Level (SIL), Signal-to-Noise Ratio (S/N) or other quantities need to be measured. Depending on the date of measurement, the measurements can be made at a fixed position or on persons during work. If high accuracy is required, it is better to choose the measurement method with microphones placed on the exposed persons. The noise generated at the location and the noise from other sources in the environment. If certain time periods are excluded from the measurement when evaluating factors such as annoyance and comfort, this must be stated in the test report. The time period includes:
The sound produced by people in a specific workplace talking to others in that workplace; the noise caused by talking into a specific workplace (such as a telephone public address system); the measurement should give the workplace-specific If the frequency, type and source of noise present at a job are typical for the workplace over a long period of time, then the measurement gives a typical potential noise exposure. If the noise exposure is to be determined for a specific work position, the measurements are carried out at that position. If a worker has more than one workplace, the equivalent continuous A-weighted municipal pressure level can be determined for each of the different workplaces or for the worker occupying each workplace. Each measurement can determine the cumulative exposure of the worker during the work period. 4.3.2 Microphone location and measurement location
The microphone location should preferably be In case the worker is not present, it is placed on the head of the worker who is already at the workplace. For other situations, when the worker must be present, in order to obtain a higher equivalent continuous A-pole sound pressure level The microphone should be placed about 0.1 m away from the entrance of the external auditory canal. The microphone of the sound exposure meter and sound level meter on the human body should be placed at the head, shoulder and 0.1 m away from the entrance of the external auditory canal. Note 1: To support the microphone, a head box or frame can be used. Note 2: The microphone should be placed on the shoulder when it is convenient. If the measuring instrument or its parts are worn by the staff, care must be taken not to interfere with their normal work, especially to avoid safety hazards. Avoid visual errors when using the instrument. If the head position of the working position is unclear and not specified by the relevant management department, the following microphone heights should be used (see GB/T 17248.2):
Standing position 1.55m ± 0.075m above the ground for standing; 0.91m ± 0.05m above the center of the seat plane placed at or close to the midpoint of the horizontal and vertical adjusters: Sitting position
In special measurement The reference direction of the microphone should be in accordance with the manufacturer's instructions (if possible, the microphone should be pointed in the line of sight of the worker at the working position). If the worker is located close to the sound source, the position and direction of the microphone should be consistent with the manufacturer's instructions (if possible, the microphone should be pointed in the line of sight of the worker at the working position). This should be specified in the measurement report. NOTE! Even small changes in the microphone position near a point source may cause changes in the sound pressure level. If a sound can be clearly heard in the workplace (see Appendix B), it means that there may be a local change in the sound pressure level. In order to determine the local change in the sound pressure level, the microphone should be placed at a distance of 0.1m to 0.5 m range The changes in the sound pressure level measured during the movement of the microphone are considered as time-varying sound levels and averaged. NOTE 2 If the microphone must be placed close to the human body, appropriate (sometimes very random) adjustments may be made by comparing the results obtained with and without the person present. This applies particularly to noise with a strong high-frequency component and to small sound sources at short distances. Normally the values with the person present are higher than those without the person present.
Detail 3: Special care should be taken when using personal sound level meters where the microphone is not located near the ear. NOTE 4: Exposure measurements using headphones (e.g. secretaries, switchboard operators, pilots, air traffic controllers) or headrests (e.g. airplane and motorcycle headrests) require special measurement methods; these methods are not covered by this standard. In areas with a large number of work positions, the following approach may be used to shorten the measurement time: divide the workplace into sections with equal microphone exposure and make measurements at a sample of typical workplaces. The average of the measurement results of these points represents the sound level value of all workplaces in the equal sound exposure zone. If the difference between the sound levels measured in different places does not exceed 5B, it can be regarded as an equal sound exposure zone. In addition, in case of doubt, all workplaces should be checked for compliance with the limit values. For some work areas, it would be more appropriate to divide them according to equal LAT sound levels. Workplaces with equal noise exposure can be: workplaces with workers doing the same job: workplaces where noise exposure is basically determined by distant noise sources (such as more than 5m to 20m away in a workshop) Note 5: In an ordinary workshop with low sound absorption, at a certain distance (about 5m20m) from the noise source, the distance doubles the sound level or decreases by 2dB~4dB. In a factory workshop with high sound absorption, the distance doubles the noise level to be less than 44-6dB. 4.3.3 Measurement time || tt || 4.3.3.1 Normalization/reference time period T, which is a time period representing the duration of a working day [usually is h(T), during which the continuous A-weighted sound pressure level is measured. During the measurement period, the squared A-weighted sound pressure level is integrated and averaged during this period. Note: The time and duration of the measurement and the duration of the measurement should be stated in the report. The selection of the measurement period should include all changes and measurements of noise levels in the workplace. Furthermore, the selection of the measurement period should make the measurement results consistent with reproducibility.
CB/T21230—2007/ISO9612:1997During the measurement period, there must be sounds that characterize the specific workplace (see 4.3.1). Two methods can be used to obtain characteristic sound exposure:
Next: If the measurement period is extended to a normalized period of more than one season, the total noise level of the rated working day will be The exposure can be determined directly, as follows: If the measured time period is shorter than the normalized reference time period, the characteristic noise exposure to be measured can be selected based on experience. 4.3.3.2 If the measurement lasts for a very short period of time, the measurement time period or the method must be chosen so that the measured noise exposure can characterize the noise exposure in the workplace and represent the noise exposure of the normalized time period. By means of a short survey/information collection of typical noise sources (such as processes, machine equipment, activities in the workplace and working environment), the proportion of time they occupy in the working day and the average sound level contributed by each part of the time period can be determined (see Appendix). The measurement time period depends on the type of noise exposure. The measurement time period can be divided into smaller measurement time periods based on the same type of noise exposure, such as The choice of duration of measurement for different tasks in the workplace or working environment will depend on the fluctuation of the noise. The duration of measurement should be long enough so that the measurement results of the noise exposure level can represent the work performed by the worker. The duration should be the entire process of a task, or a part of the task, or, as required, several repetitions of the task in order to stabilize the exposure level or equivalent continuous A-weighted sound pressure level reading within 0.5 dB. The minimum duration should be 5 hours. If the noise has obvious periodicity, the minimum duration should include at least one cycle: otherwise it should include multiple complete cycles. The sampling process can be extended to multiple work ports and averaged (see Appendix D). 4.3.4 Determination of equivalent continuous A-weighted sound pressure level The best way to measure the equivalent continuous A-weighted sound pressure level within a specified measurement period T is to use an integrating average sound level meter. If the level fluctuations of the sound level meter are not large [see note], the average of the readings indicated by the meter (or recorder) is approximately equal to the equivalent continuous A-weighted sound pressure level L?.
Note: When the total change of the meter measured by the time-weighted slow gear is within the range of 5, it can be considered that the onset of the obstruction is not great. If the measurement time period T is divided into smaller time periods, the equivalent continuous A-weighted sound pressure level (unit: B) in the time period T can be calculated using the formula (1>:
LAatr=10 lg
wherein ·
T10-am
equivalent continuous A-weighted sound pressure level in time period T, in decibels (dR); TT in seconds (S);
the total number of each time period T.
4.3.5 Normalized equivalent continuous A-weighted sound pressure level for rated 8-hour working day 1
In order to compare the noise exposure of working days of different durations, in many cases, it is hoped to normalize the daily occupational noise exposure of working hours of different durations to the noise exposure of rated 8-hour working days. In this standard, the 8-hour time period is expressed as, the normalized daily exposure level (in dB) is obtained by formula (2): Lex-Iann +10 1e T
Note: The exposure level normalized to 8-hour working day (unit: dB) can be obtained by solving the daily A-weighted exposure EF (unit: S) by the formula:
I-ex.ab-10 1g L.15x105
Table 1 gives some selected values and their corresponding 8-hour working normalized exposure level values, -(3)
CB/T21230-—2007/1S09612:1997 Table 1 Daily A-weighted sound exposure E and the corresponding exposure level normalized to rated 8-hour working day Ea.netPasx1or)
Lexedn
4.3.6 The best method for determining A-weighted sound exposure E is to use a personal sound exposure meter or an integral sound level meter. The relationship between E and L is given by formula (4): Ea.T.-ph. T.10A.T./
Wherein!
Pu-2×10- Pa:
T, unit is s.
If the measurement time T is divided into smaller time periods T and EA.Ta is measured within T., then EA.T is calculated by formula (5): Ea,T.
Determination of normalized daily exposure sound level for multiple days 4.3.7
If you want to calculate the average daily exposure, for example, if the rated normalized explosive sound level of one week's exposure is considered, then the average value of the worker-year (unit: dB) during this period can be calculated by formula (6) from the daily (Lxa) value to obtain: Lkx-10 Note: When the average is taken over a period of more than one week, the maximum and minimum daytime exposure sound levels shall be normalized to the equivalent continuous A-weighted sound pressure level for a rated 40-hour work week. (6) If the normalized exposure sound level for one week is considered, Lx-the average value for one week (unit: dB) can be calculated by formula (6) in 43.7: Lex.w=10 1g 1100.14/gx.ab. 4.3.9 Group sound exposure needs CB/T21230-2007/ISO9612:1997 In some cases, it is appropriate to calculate group sound exposure. This does not require sampling of every individual to obtain reliable results. The reference introduces statistical sampling methods for group noise exposure measurements. 4.3.10 Evaluation sound level
The evaluation sound level (see GB/T3222.1) is used to characterize the total impact of noise in the working environment. For this purpose, the equivalent continuous A-weighted sound pressure level can be corrected according to the pure tone and/or pulse characteristics and normalized to the rated exposure level for an 8-hour workday. The guidance on pure tone and pulse correction in Appendix C introduces the normalized sound level using this correction. 4.4 Spectral analysis
If noise spectrum data at the worker's operating position is required, for example for the design of sound barriers or sound absorption measures, a spectral analysis can be performed using a multiple-band or 1/3-band filter (see 4.2.2). Choose the appropriate measurement time according to the spectrum analysis, such as the time period when the highest upper value appears, the time period when the special operating conditions contain the pure sound. To prevent the false results of the spectrum analysis, it is recommended to average through a series of repeated and independent measurements. 4.5 Infrasound Ultrasound
If the noise at the operator's operating position is mainly infrasound (frequency less than 20Hz), it is recommended to use a 1/3 band filter or a bandwidth cleaner with the characteristics specified in IS07196:1995 for additional measurement. If the noise at the operator's operating position is mainly ultrasonic or high-frequency audible sound, the measurement should be carried out using a band filter or a pull-band filter with a center frequency that covers the frequency range of interest by 1/3 octave, but at least includes the center frequency of 16000Hz to 40000Hz. The sound level meter or integrating sound level meter used should comply with the Class 1 instrument in TEC61672-1.2002 and have a sound response higher than 12000Hz. The measurement period should be selected so that the measurement results can represent the long-term average situation. At least information on the approximate sound level in the infrasound and ultrasonic frequency range should be provided.
4.6 Special noise characteristics
When special noise characteristics cannot be indicated by the measurements specified above, they should be stated in the measurement report and supported and supplemented by additional measurement results, such as oscilloscopes, cumulative percentage sound level records, upper value L value, noise pulse duration, sharpness, etc. Note: Lm is the maximum A-weighted re-pressure level weighted by the membrane impulse time. Examples of special characteristics are as follows:
Liangshi source
Feed
Machines operated by workers
Other machines in the same workshop:
Outside the workshop (traffic):
Workers talking:
Forklifts or other trucks.
Machine sounds:
Intelligible or intelligible language!
Animal sound
Telephone ringing:
Traffic noise+
Indication of non-or resting family reserve point automobile province
GB/T21230-2007/ISO9612:1997
Noise measurement
5 Application of measurement results
5.1 General
Stable:
Unstable,
Pulsed:
Pulsed:
Smiling:
Rhythmic! Periodic,
perceptual band:
perceptual band:
pure tone low or high;
screaming
sharp sound,
commercial information services
The methods described in Chapter 4 can be used to evaluate the different effects of occupational noise on the human body, the details are as follows: the application of measurement results and the evaluation of the energy noise requires the corresponding measurement method and measurement space. If the measurement is for comparison with the specified guide or limit, the expected overall accuracy will usually increase, the measured value is closer to the limit, and the overall accuracy depends on the precision of the measurement and the sampling accuracy (see Appendix). This chapter describes the application of measurements in the evaluation of the different effects of ambient noise on workers. Application of the results of the measurements given in 5.5 5.2 Effects on hearing The quantities used to assess the effects of noise on hearing are the A-weighted exposure level converted to an 8-hour workday (duration TC = 8h), the A-weighted exposure level, the EA, the pure tone corrected 8-hour assessment sound level. Appendix C gives details of the peak sound pressure level, the C-weighted peak sound pressure level, and the C-weighted peak sound pressure level. These quantities can be derived from measurements using an integrating sound level meter or a personal de-escalator as described in Section 5. These quantities are used to determine occupational noise exposure (GB/T 143G, GB/T 14366) and the risk assessment standard for occupational noise). In addition, the risk assessment will also need to be associated with the maximum point pressure level and its duration (occupational noise norm), and the A-weighted and C-weighted sound pressure levels need to be evaluated by hearing instruments (GB/T7584.2), while the sound control engineering and hearing protection plan both require noise probability analysis.
Hearing loss can be temporary or permanent. GB/T14366 is related to noise-induced permanent hearing loss (NIPTS). NIPTS is an irreversible neurological hearing loss caused by long-term noise exposure. It is completely caused by the noise exposure alone and has nothing to do with other reasons. The permanent hearing loss of noise-exposed people is determined by the age-related hearing level and NIPTS. Since there are significant differences in the sensitivity of human hearing to NIPTS and age-related hearing loss, the danger of a noisy environment can be described as "hearing damage risk". The risk of hearing loss is expressed as the percentage increase in the population exposed to noise in a noisy environment whose hearing level exceeds a given warning limit, which is related to the hearing level of a population not exposed to noise, but who is otherwise equivalent to the exposed population. For impulse noise with instantaneous peak sound pressure levels exceeding 140 dB, the assessment of the risk of damage in GB/T 14366 has not been confirmed by statistical data and should not be used. Based on the noise measurements conducted in Chapter 4, the relevant management agency can assess the risk of noise-induced hearing loss from occupational sound exposure and determine the requirements for a hearing protection program, including hearing monitoring, wearing or appropriate hearing protectors, and the best engineering or management measures to reduce individual or group noise.Appendix C explains: Peak sound pressure level is C-weighted peak L. These quantities can be derived by measurement using an integrating sound level meter or a personal sound de-escalator as described in the first clause. These quantities are used to determine occupational noise exposure (GB/T 143G, potential noise-induced hearing loss (GB/T 14366) and risk assessment (C occupational noise specification). In addition, risk assessments will also need to relate the maximum point pressure level value and its duration (occupational noise specification), and also need to relate the A-weighted and C-weighted sound pressure levels to the evaluation of hearing aids (GB/T 7584.2), while sound control engineering and hearing protection programs require noise compliance analysis. Hearing loss can be temporary or permanent, GB/T 14366 is related to noise-induced permanent hearing loss (NIPTS). NIPTS is an irreversible neurological hearing loss caused by long-term noise exposure. It is a hearing loss caused entirely by the noise exposure alone and has nothing to do with other reasons. The permanent hearing loss of noise-exposed people is determined by the age-related hearing level and NIPTS. Since there are significant differences in the sensitivity of human hearing to NIPTS and age-related hearing loss, the danger of a noise environment can be described by the "risk of hearing loss". The risk of hearing loss is expressed by the percentage increase in the number of people in a noise environment who are exposed to noise and whose hearing level exceeds a given warning limit. The warning limit is related to the hearing level of the non-noise-exposed population, but the non-noise-exposed population is equivalent to the noise-exposed population in other aspects. For impulse noise with an instantaneous peak sound pressure level exceeding 140dB, the assessment of the risk of damage in GB/T14366 has not been confirmed by statistical data and should not be adopted. Based on the noise measurements conducted in Chapter 4, appropriate regulatory agencies can assess the risk of noise-induced hearing loss from occupational sound exposure and determine the requirements for a hearing conservation program, including hearing monitoring, the wearing or appropriate hearing protectors, and engineering or management measures to best reduce individual or group noise exposure.Appendix C explains: Peak sound pressure level is C-weighted peak L. These quantities can be derived by measurement using an integrating sound level meter or a personal sound de-escalator as described in the first clause. These quantities are used to determine occupational noise exposure (GB/T 143G, potential noise-induced hearing loss (GB/T 14366) and risk assessment (C occupational noise specification). In addition, risk assessments will also need to relate the maximum point pressure level value and its duration (occupational noise specification), and also need to relate the A-weighted and C-weighted sound pressure levels to the evaluation of hearing aids (GB/T 7584.2), while sound control engineering and hearing protection programs require noise compliance analysis. Hearing loss can be temporary or permanent, GB/T 14366 is related to noise-induced permanent hearing loss (NIPTS). NIPTS is an irreversible neurological hearing loss caused by long-term noise exposure. It is a hearing loss caused entirely by the noise exposure alone and has nothing to do with other reasons. The permanent hearing loss of noise-exposed people is determined by the age-related hearing level and NIPTS. Since there are significant differences in the sensitivity of human hearing to NIPTS and age-related hearing loss, the danger of a noise environment can be described by the "risk of hearing loss". The risk of hearing loss is expressed by the percentage increase in the number of people in a noise environment who are exposed to noise and whose hearing level exceeds a given warning limit. The warning limit is related to the hearing level of the non-noise-exposed population, but the non-noise-exposed population is equivalent to the noise-exposed population in other aspects. For impulse noise with an instantaneous peak sound pressure level exceeding 140dB, the assessment of the risk of damage in GB/T14366 has not been confirmed by statistical data and should not be adopted. Based on the noise measurements conducted in Chapter 4, appropriate regulatory agencies can assess the risk of noise-induced hearing loss from occupational sound exposure and determine the requirements for a hearing conservation program, including hearing monitoring, the wearing or appropriate hearing protectors, and engineering or management measures to best reduce individual or group noise exposure.
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