- At sea level and at 15°C , the density of air is 1.275 kg/m3. This is the value of the ISA or International Standard Atmosphere.
- At 20 °C and 101.325 kPa, the density of dry air is 1.2041 kg/m3.
- At 70 °F and 14.696 psi, the density of dry air is 0.074887 lbm/ft3.
The density of air decreases as you gain altitude. For example, air is less dense in Denver than in Miami. The density of air decreases as you increase temperature, providing the volume of the gas is allowed to change. As an example, air would be expected to be less dense on a hot summer day versus a cold winter day, providing other factors remain the same. Another example of this would be a hot air balloon rising into a cooler atmosphere.
Kidder, Frank. Architects' and Builders' Handbook, p. 1569.
Lewis, Richard J., Sr. Hawley's Condensed Chemical Dictionary, 12th ed., p. 28.