So, "Cooling Fan Manufacturer" noise test what standard? For air supply fan and sound level parameters are standard laboratory tests, the American Society of Engineers, Association of air movement and control in strict accordance with the respective values developed a comprehensive testing standards, if we want to know the rough "Cooling Fan Manufacturer" of noise ratio is the number refers to the size of the sound level at a certain point in space the size of about one meter away from the fan in front of the place, when the cooling fan emit sound from all directions, different pressure levels may exist in another place. Wind source for product testing is very strict, fully enclosed, soundproofed rooms and advanced testing equipment to make the data more accurate. For more "Cooling Fan Manufacturer" information source contact the marketing department of the Wind.