Required Air Flow to Remove Moisture

The required air flow to remove moisture or water vapor production in a room can be calculated as 

L = G / (x_r - x_m)                                    (1)

where 

L = required air flow (kg/h)

G = moisture or vapor production in the room (kg/h)

x_r = humidity ratio in room air (kg_H2O/kg dry air)

x_m = humidity ratio in make-up air (kg_H2O/kg dry air)

Example - Removing Moisture from a Room

Required air flow to keep a humidity ratio of 0.010 (kg_H2O/kg dry air) in a room with input air humidity ratio of 0.001 (kg_H2O/kg dry air) and vapor production 100 (kg/h) can be calculated as 

L = (100 kg/h) / ((0.010 kg_H2O/kg dry air) - (0.001 kg_H2O/kg dry air))  

  = 11020 (kg/h)