Standard air definition:

Air density 1.2 kg/m³ (0.075 lbs./cuft.)
Atmosphere 760 mmHg (1 bar , 29.92 in.Hg)
Temperature 20°C
Relative humidity 65%

Unit Conversion:

Air Pressure:
1 atm = 760 mmHg = 760 Torr = 1.0332 kgf/cm²
1 kgf/cm² = 14.223 Psi = 10010 mmAq
1 Psi = 703.79 mmAq
1 Pa = 0.102 mmAq
1 mbar = 10.197 mmAq
1 mmHg = 13.6 mmAq
1 Torr = 133.3 Pa = 1.333 mbar = 13.593 mmAq

Air Flow:
CFM: Cubic Feet per Minute (ft³/min)
CMM: Cubic Meter per Minute (m³/min)
1 CMM = 35.3 CFM = 1000 L/Min

Temperature:
°F=9/5°C+32, °C =5/9(°F -32)
Absolute Kelvin °K=273.15+°C
Absolute Rankine °R=459.67+°F

Air density:
1 kg/m³=0.0625 lbs/ft³

Relativity of related values:

Effect of speed change
Horsepower(kW), Static Pressure(Ps), Air Flow(Q) and Speed(S)
Q2=Q1x[S2/S1]
Ps2=Ps1x[S2/S1]
kW2=kW1x[S2/S1]

Effect of Altitude and temperature change
Horsepower(kW), Static Pressure(Ps), and Air Density(D)
Ps2=Ps1x[D2/D1]
KW2=kW1x[D2/D1]

Effect of Temperature Change
Static Pressure(Ps) and Absolute Temperature[T(°K)]
Ps2=Ps1x[T2/T1]

Effect of Altitude Change
Air Flow(Q) and Air pressure of varied Altitude(Pa)
Q2=Q1x[Pa2/Pa1]