ahu formulas

Not enough information to constitute a good question, much less to formulate a good answer. What are you trying to do, especially regarding to the air stream you are trying to cool, the temperatures and humidities you want to obtain, the insulation qualities of the room involved, the heat of product in the room, etc.?

This is an engineering type of queston, and it needs engineering type of data to be answered.

(Total volume of room in ft³ x required no. of air changes/hour) ÷ 60. What factors to consider depenp upon requirements.

cfm is cubic feet per minute of "free air". That is a cubic foot of air at STP = standard temperature (62F - 20C) and pressure (1 atmosphere = 14.7 psi, 1bar, ~100kPa).

E.g a 7 cfm compressor means it supplies a flow equal to 7 cubic feet of air when it is re-expanded to 1 atm.

This is also been asked on another thread here

p911