cause a ceiling fan to fall. Ceiling fans are secured by clevis pins locked with either split pins or R-clips, so wobbling will not have an effect on the fan's security, unless of course, the pins/clips were not secured. To date, there are no reports of a fan wobbling itself off the ceiling and falling. However, a severe wobble can cause light fixture shades or covers to gradually loosen over time and potentially fall, posing a risk of injury to anyone under the fan, and also from any resulting broken glass. When the MythBusters were designing a fan with the goal of chopping off someone's head, Scottie used an edge finder to find the exact center of their blades with the aim of eliminating potentially very dangerous wobbling of their steel blades. Wobbling may be reduced by measuring the tip of each blade from a fixed point on the ceiling (or floor) and ensuring each is equal. If the fan has a metal plate between the motor and blade, this may be gently adjusted by bending. It can also be reduced by making sure all blades have the same pitch, and all blades have the same distance from adjacent blades. It can also be reduced by having balancing weight on the blades. See also Attic fan Whole-house fan Window fan Air cooler Fan death Punkah References External links Home appliances Cooling technology Ventilation fans 19th-century inventions German inventions American inventions