A fan is a rotating device used to create a pressure difference. That differential results in the movement of air. The movement of air is measured in cubic feet per minute or CFM…

Efficiency is an important consideration when selecting a fan. There are two types of fan efficiency-fan static efficiency and fan total efficiency….

System effect is the difference between published performance and installed performance. Fans are performance tested in a controlled environment where installation conditions are ideal….

To consider the quality of sound, we must consider the frequency that sound pressure variations occur within. Frequency is the number of pressure variations per second and is measured on hertz. Fan sound is broadband,…….

Once the fan is selected, the fan curve needs to be reviewed. There are two major things to look for. Is the fan stable? And does it allow for adjustment?….