If you are installing a ceiling fan for your home, only use a residential one, which typically has 4 or more blades.
Generally, a ceiling fan should be 8 or 9 feet from floor to ceiling, and no part of the fan should be less than 7 feet away from the floor. These measurements add various advantages. One advantage is that ensuring proper clearance avoids accidental contact with the fan. Also, when the fan has the right distance from the floor, the downward air movement is maximized and the air flow is right where you want it.
What if your ceiling is much higher than the average home? Simply drop the fan to the desired height, which can easily be done by an experienced installer.
These details may seem like a lot to remember but if are willing to take the time to install a ceiling fan correctly and safely, you can enjoy the benefits of this simple solution to an airflow problem.