What is the difference between "CFM" and "SCFM"?
SCFM = Standard Cubic Feet per Minute. This is 1 cubic foot of free air at standard atmospheric temperature and pressure (the standard conditions are usually 68°F and 14.7 PSIA).
CFM = Cubic Feet per Minute. This is sometimes incorrectly used interchangeably with SCFM meaning free air. Unless the pressure and temperature are specified with CFM, the actual volume of gas flow cannot be determined.