What is CADR? How much CADR of Mi Air Purifier?

Product model: 
The Clean Air Delivery Rate (CADR) is the main index used by international authoritative organizations to evaluate the Air purification efficiency.
CADR is the rate of clean air output from air purifiers tested by the American Home Appliance Manufacturers Association (AHAM) in accordance with stringent testing standards.The higher CADR value, the higher purification efficiency of the purifier.
In high-speed mode, the CADR of mi air purifier is 406m3/h, and the applicable area is 28.4~48.7m2.In sleep mode, the CADR of mi air purifier is about 100 m3/h, and in automatic mode, the CADR range is between 100 and 406 m3/h.
Notes: 
Applicable area =CADR× (0.07~0.12)