SIZE / SPAN
It is the diameter of the circle traced out by the extreme tips of the fan blades, while rotating. It is usually measured in mm.
Volume of air swept out by the ceiling fan. It is usually measured in Cubic Meter per Minute (CMM) or Cubic Feet per Minute (CFM)
The electricity consumed by the ceiling fan to operate. It is measured in Watt (W).
BEE has a star rating system for ceiling fans with 1200mm span and a minimum of 210 CMM. It is a trusted, government backed system that rates the fans according to its service value.
The following are the star rating guidelines from the BEE website.
Bureau of Energy Efficiency (BEE) gives a star rating based on ‘service value’. It is the ratio of maximum Air delivery (CMM) and Input power (W).
Warning:- Some manufacturers reduce the air delivery to achieve higher ‘service value’ so make sure to check the air delivery along with the service value.