Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

This is an AMP page - Open full page! for all features.

• the most efficient way to navigate the Engineering ToolBox!

# Carbon Dioxide Concentration in Rooms Occupied with People

## Carbon dioxide concentration in a room may indicate air quality and ventilation system efficiency.

The carbon dioxide concentration in a room can be used to indicate air quality.

The Carbon dioxide concentration in a room filled with persons after a time - t - can be calculated 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 (1/h)

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)

Note that this equation can be used to calculate the concentration of any pollution as long as the pollution substance is homogeneous mixed with the air.

### CO2 Concentration Calculator

q - carbon dioxide supplied to the room pr. person (m3/h person)

no. of persons in the room

V - volume of the room (m3)

n - number of air shifts per hour (1/h)

t - time (hour, h)

ci - carbon dioxide concentration in the make up air*) (m3/m3)

c0 - carbon dioxide concentration in the room at start, t = 0 (m3/m3)

*) normal carbon dioxide concentration in outside air is aprox. 400 ppm (0.0004 m3/m3).

### Example - Carbon Dioxide Concentration in a Cinema

With an approximately carbon dioxide emission per person in a cinema of 0.05 m3/h - the CO2 emission from 100 persons can be calculated to approximately 5 m3/h.

If the carbon dioxide concentration when people enters the room - and in the inlet air - is close to zero, the CO2 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 1/h) (1 h))] + ((0 m3/m3) - (0.0004 m3/m3)) (1 / e(1 1/h)(1 h)) + (0.0004 m3/m3)

= 0.0067 m3/m3 (6700 ppm)

Note! - that with 6700 ppm (0.0067 m3/m3) of CO2 in the air - adverse health effects may be expected. One air shift per hour as used in this example is not enough.

## Related Topics

• Physiology - Human physiology, air quality and comfort temperatures, activity and metabolic rates, health effects of carbon monoxide and more.
• Fluid Mechanics - The study of fluids - liquids and gases. Involving velocity, pressure, density and temperature as functions of space and time.
• Ventilation - Systems for ventilation and air handling - air change rates, ducts and pressure drops, charts and diagrams and more.

## Search Engineering ToolBox

• the most efficient way to navigate the Engineering ToolBox!

## SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp from the Sketchup Extension Warehouse!

## Privacy

We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Temperature

oC
oF

Length

m
km
in
ft
yards
miles
naut miles

Area

m2
km2
in2
ft2
miles2
acres

Volume

m3
liters
in3
ft3
us gal

Weight

kgf
N
lbf

Velocity

m/s
km/h
ft/min
ft/s
mph
knots

Pressure

Pa (N/m2)
bar
mm H2O
kg/cm2
psi
inches H2O

Flow

m3/s
m3/h
US gpm
cfm

3 30