Pressure measurement can improve building air quality
“The oxygen consumption rate is 0.36 l/min (0.013 cfm) when the activity level is 1.2 met (met = level of body activity such as filing/seated). For ventilation at a rate of 15 cfm and an activity of 1.2 met units, the room oxygen level will be reduced from an outdoor concentration to 20.9%. Thus, the oxygen content of the room is reduced from 21.0% to 20.9%, a change of only 0.5%. The carbon dioxide is raised from the background of 0.03% (300 ppm) to 0.1% (1,000 ppm), a change of 230%. Thus dilution of carbon dioxide is clearly more significant than replacing oxygen.”
This explanation indicates that the oxygen supply is not the primary reason that buildings require ventilation. The odors (contaminants, see Table 1) produced by people, and gases (odors) from furnishings, office, and manufacturing equipment are the primary reason buildings require ventilation.