Carbon Dioxide (CO2)

What is Carbon dioxide?

Carbon dioxide (CO2) is a surrogate for indoor pollutants emitted by humans and correlates with human metabolic activity. Indoor levels are an indicator of the adequacy of outdoor air ventilation relative to indoor occupant density.

Sources of Carbon dioxide

Carbon dioxide is a product of human or animal respiration (or breathing). Other non living sources of the gas may include space heaters, clothes dryers, stoves, or any other unvented gas-burning appliance. The gas may also infiltrate the home from an outdoor source, in which case the cause is most likely to be a large industrial area or any processes which involve the burning of fossil fuels.

Factors affecting CO2 levels indoors

The levels of CO2 in indoors are dependant upon: the number of people present, how long an area has been occupied, the amount of outdoor fresh air entering the area, the size of the room or area, the outdoor fresh air concentration.

Possible Health Implications

Occupants may experience health effects in buildings where CO2 is elevated, but the symptoms are usually due to other contaminants in the air that also build up as a result of insufficient ventilation. At a moderate level, carbon dioxide can create feelings of stuffiness and general discomfort. At high levels, the carbon dioxide itself can cause headache, dizziness, nausea, and other symptoms. This could occur when exposed to levels above 5,000 ppm for many hours. At even higher levels CO2 can cause asphyxiation as it replaces oxygen in the blood—exposure to concentrations around 40,000 ppm is immediately dangerous to life and health. However, CO2 poisoning is not common.

Mitigation strategies

Adequate ventilation strategies should be adopted to reduce CO2 build up. Ensuring required ventilation in air tight building will not only save energy, but reduce the CO2 level, improve thermal comfort, control moisture, reduce indoor pollution and diminish some health problems.

To read more on effect of CO2 on Indoor Air Quality, please visit the following links:

http://www.aerias.org/DesktopModules/ArticleDetail.aspx?articleId=138&spaceid=2&su
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=149392
http://www.comag-ir.com/download/Sick%20leave%20among%20office%20workers.pdf
http://www.hc-sc.gc.ca/ewh-semt/pubs/air/office_building-immeubles_bureaux/co2-eng.php
http://www.propex.com/C_f_env_co2.htm

Singapore National Environment Agency recommends that the maximum threshold level for carbon dioxide should not exceed 1000ppm (or 0.1%) based on "Guidelines for Good Indoor Air Quality in Office Premises".

 

Need Professional Assistance?

Please feel free to contact Mr Charn @ Tel: 6241 9443/ Hp: 9321 9321, Mr. Moshood Hp: 93225506 or email mof@iaqsg.com if you are interested in having your indoor air tested or audited to monitor and control ozone level in your indoor environment.