Methods of noise detection:

1. Simple on-site detection, commonly used ordinary sound level meter (also called noise meter) to detect the noise of equipment. During on-site inspection, first estimate the size of the equipment, and then determine the location of the measuring point.

2. When using this method, the ISO near-field test method should pay attention to the following points:

(1) Draw the envelope of the whole equipment in the plane.

(2) The environment is similar to the free field, that is, there is almost no reflection, the distance of the measuring point is doubled, and the noise is reduced by 6 decibels.

(3) The measurement height is required to be at 1/2~1/3 of the height of the equipment.

(4) The distance between the measuring points should ensure that the sound pressure level difference between adjacent points does not exceed 5 decibels.

(5) Calculation requirements for measured values: when the difference between the maximum value and the minimum value of each measuring point does not exceed 5 dB, only the arithmetic mean is required; when the difference between the maximum value and the minimum value exceeds 5 dB, energy is used. The average method is calculated.