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Silent fan manufacturers: Silent fan and decibel level analo

Silent fan manufacturers: Silent fan and decibel level analogy
 
On the market, many businesses will launch silent products. What is a silent product? In fact, the definition standards of different industries are different, and the national standard is not clearly defined. The so-called silent and ultra-quiet of the merchants are generally corporate standards and are determined by the manufacturers. However, in my country’s National Standards on Noise Limits for Household and Similar Electrical Appliances, there are mandatory provisions on the noise limits for household appliances. For example, the maximum noise limits for washing and dehydration of washing machines are 62 decibels and 72 decibels respectively; according to the cooling power, the air-conditioned room The limit of machine noise is 40-63 decibels.
 
From the perspective of human perception, it is generally less than 40 decibels, which can be called silent, and less than 20 decibels, can be called super silent. For industries that do not have national standards, we generally use this as the standard.
 
In an anechoic room with a background noise of 8dB-A, our 20x20x10mm and 25x25x7mm cooling fans can achieve the lowest noise of 18dB-A, which is less than 20 decibels. They can be called ultra-quiet fans, and according to the classification standards of human perception , Our small and medium size fans can reach the silent fan level.
 
Decibel level. For many people, the decibel of volume is a very abstract concept. Below we introduce the volume above 70 decibels by analogy:
190 dB cause death
140 dB The highest threshold defined by the European Union to cause complete hearing loss
139 dB the shouts of World Cup fans
130 dB sound of rocket launch
125 dB the sound of a jet plane taking off
120 dB staying in this environment for more than one minute will cause temporary deafness
110 dB the sound of a propeller plane taking off, the sound of a rock concert
105 dB permanently damage hearing
100 dB the sound of a pneumatic drilling machine, the sound of a compression hammer beating a heavy object
90 dB noisy bar environment sound, electric saw sawing wood
85 dB and below will not damage the hair cells in the cochlea
80 dB noisy office, sound on the highway
75 dB upper limit of human ear comfort
70 dB street ambient sound