Resources, Tools and Basic Information for Engineering and Design of Technical Applications!
mobile - visible on handheld devices - alternatively go to www.engineeringtoolbox.com!
Engineering ToolBox > Carbon Dioxide Concentration in Rooms
The carbon dioxide concentration in a room may be used as an indication of the air quality.
The carbon dioxide concentration in a room with a number of persons can after a time - t - be expressed as
c = (q / n V) [1 - (1 / en t)] + (c0 + ci) (1 / en t) + ci (1)
where
c = carbon dioxide concentration in the room (m3/m3)
q = carbon dioxide supplied to the room (m3/h)
V = volume of the room (m3)
e = the constant 2.718.....
n = number of air shifts per hour (h-1)
t = time (hour, h)
ci = carbon dioxide concentration in the inlet ventilation air (m3/m3)
c0 = carbon dioxide concentration in the room at start, t = 0 (m3/m3)
When the carbon dioxide emission from a person sitting in an cinema is approximately 0.05 m3/h the emission from 100 people is approximately 5 m3/h. If the pollution concentration at start up and in the inlet air is close to zero, the pollution concentration in a 500 m3 cinema after one hour and with one air shift per hour, can be calculated as:
c = ( (5 m3/h) / (1 h-1) (500 m3) ) [1 - (1 / e(1 h-1) (1 h))] + (0 + 0) (1 / e(1 h-1) (1 h)) + 0
= 0.006 m3/m3