Noise inspections include simple on-site testing and ISO near-field testing. Simply turn on the noise detection system and it will detect the ambient noise condition and indicate the decibel level instantly. Ambient noise exceeding 40 dB during the daytime or 30 dB at night is a violation of the Urban Area Noise Standard (UANS).
1. Simple on-site inspection:
Common ordinary noise detector (also called noise meter) to detect the noise of the instrument. On-site testing, the first calculation of mechanical equipment size, followed by a clear geographic location of the measurement point.
Equipment testing of machinery and equipment for the larger size of D: D < 1 meter, the test case from the surface of the mechanical equipment for 30 cm. D is 1 meter, the test case from the surface of the mechanical equipment for 1 m. D> 1 meter, the test case from the surface of the mechanical equipment for 3 meters. General mechanical equipment, to choose 4 test cases, large mechanical equipment to measure 6 points.
2. ISO near-field test method:
(1) in the plane to draw the envelope of the entire equipment mechanical equipment.
(2) environment similar to the free field, that is, there is almost no reflection, the distance between the measurement points increased exponentially, the noise is reduced by 6 dB.
(3) Measurement of the relative height of the standard in the relative height of the machinery and equipment at 1/3-1/2.
(4) The spacing of measurement points to ensure that the sound pressure level difference between neighboring points does not exceed 5 dB.
(5) Calculation standard of the measured value: when the difference between the larger value and the smaller value of each measurement point is not more than 5 dB, only the arithmetic average is required; when the difference between the larger value and the smaller value is more than 5 dB, then the calculation should be done by means of energy averaging.