Noise meter - influencing factors and measurement
1. From the measurement object, it can be divided into the characteristic measurement of environmental noise (sound field) and the measurement of sound source characteristics.
2. From the time characteristics of the sound source or sound field, it can be divided into steady-state noise measurement and unsteady-state noise measurement. Non-stationary noise can be divided into periodic noise, irregular noise and pulse sound.
3. From the frequency characteristics of the sound source or sound field, it can be divided into broadband noise, narrowband noise and noise containing prominent pure tone components.
4. From the accuracy of measurement requirements, it can be divided into precision measurement, engineering measurement and noise survey.
Noise Meter - Measurement
For the sake of uniformity, some noise measurement standards have been formulated internationally and domestically. These standards not only specify the method of noise measurement, but also specify the technical requirements for the use of noise meters. These standards can be used to better select suitable noise meter.
1. Acoustics - environmental noise measurement
The measurement method can be in accordance with GB3222-94 "Acoustic Environmental Noise Measurement Method"
The measured values are required to include LA, LAeq, LN (L5, L10, L50, L90, L95), Ld, and Ln. The accuracy of the instrument is required to be type 2 or above. , Acoustic performance and measurement method "stipulations.
2. Urban environmental noise measurement
The measurement method can be in accordance with GB/T14623-93 "Measurement Method of Urban Regional Environmental Noise"
The measured values are required to include LA, LAeq, LN (L10, L50, L90), Ld, Ln, and the accuracy of the instrument is required to be type 2 or above integral noise meter and environmental noise automatic monitoring instrument, and the performance meets
Comply with the provisions of GB3785 "Electrical and Acoustic Performance and Measurement Methods of Noise Meter".
3. Noise measurement of industrial enterprises
The measurement method can be in accordance with GB12349-90 "Measurement method of noise at the boundary of industrial enterprises"
The measured values are required to have LA, LAeq, and the accuracy of the instrument is required to be a noise meter of type 2 or above and an automatic monitoring instrument for environmental noise.
4. Noise measurement of construction site
The measurement method can be in accordance with the requirements of GB12524-90 "Measurement Method of Noise at the Boundary of Construction Sites", the measurement value has LAeq, and the accuracy of the instrument is required to be type 2 or above integral noise meter and automatic monitoring instrument for environmental noise (dynamic range is not less than 50dB), and the performance meets GB3785 "Noise Meter Electricity, Acoustic Performance and Measurement Methods".
5. Motor vehicle stationary noise measurement
The measurement method can be in accordance with GB/T14365-93 "Acoustic Motor Vehicle Stationary Noise Measurement Method", which requires that the measured value has an A-weighted "fast" characteristic sound pressure level Lp, and requires a type 1 or type 2 noise meter for the accuracy of the instrument, and its performance conforms to GB3785 " Noise Meter Electricity, Acoustic Performance and Measurement Methods".
6. Measurement of radiation noise of railway rolling stock
The measurement method can be in accordance with GB/T5111-95 "Radiation Noise Measurement of Acoustic Railway Rolling Stock"
The measured value is required to have LPAF, and spectrum analysis and measurement can also be performed. The accuracy of the instrument is required to be type 2 or above integrated noise meter and environmental noise automatic monitoring instrument.
7. Inland waterway and ship noise measurement
The measurement method can be in accordance with GB/T4964-85 "Measurement of Radiated Noise from Ships in Inland Waterways and Ports"
The measured value is required to have A-weighted "fast" characteristic sound pressure level Lp, and A-weighted "pulse" sound pressure level Lp. The accuracy of the instrument is required to be type 1 or type 2 noise meter, and the performance is in line with GB3785 "Noise Meter Electrical, Acoustic Performance and Measuring method "stipulations.
8. Aircraft noise measurement
The measurement method can be in accordance with GB9661-88 "Measurement method of aircraft noise around the airport"
It is required that the measured value has A-weighted "fast" characteristic sound pressure level Lp, and the effective perceived noise level of aircraft noise Lepn. The accuracy of the instrument requires a noise meter of type 2 or above and an automatic monitoring instrument for environmental noise. The performance conforms to GB3785 "Noise meter electrical and acoustic performance and measurement methods".
9. Measurement of sound power level of noise source
The measurement method can be in accordance with GB/T16538-96 "Acoustic Sound Pressure Method Determination of Noise Source Sound Power Level Using Standard Sound Source Simple Method"
The test instrument uses the sound level of type 2 or above specified in GB3785, and measures it with a slow gear. It is best to use an extension cable or an extension rod between the noise meter and the microphone.
10. Environmental vibration measurement
The measurement method can be in accordance with GB10071-88 "Measurement Method of Urban Regional Environmental Vibration"
It is required to measure VAL, VL, VLZ, VLZN. Measuring instruments shall comply with the instruments for measuring environmental vibration specified in ISO/DP8041-84.
