Air at a temperature of 68 °F, a pressure of 14.70 psia and a relative humidity of 36 per cent (0.0750 density) (as per A.S.M.E. however in the gas industry the temperature of standard air is usually given as 60 °F. ( Unless specifically stated otherwise) ( 060)
Air weighing 0.7488 pound per cubic foot, which is air at 68oF dry bulb and 50% relative humidity at a barometric pressure of 29.92 in. Hg.
Dry air weighing 0.075 lb per cu ft at sea level (29.92" Barometric Pressure) and 70 °F.