Flow Calculation for Gases
QG = Gas Flow in Standard Cubic Feet per Hour P1 = Upstream (inlet) pressure in psia T = Absolute temperature in ºR. (ºF + 460) P2 = Downstream (outlet) pressure in psia psia = Absolute pressure. This is psig (gage pressure) plus (atmospheric pressure) = Specific Gravity of medium where air at 70º F and psia = Example: