Abstract:
It is well known that adverse health conditions could develop due to outdoor air
pollutants, such as, C02, CO, S02, NO,, PM (particulate matter), VOC (Volatile
Organic Compounds), when people are outdoors, while travelling or working. Since
most of the people spend 80-90% of their time indoors, at home or place of work, the
presence of these air pollutants could adversely their health while indoors, as well.
Hence, minimizing the presence of air pollutants, by taking appropriate measures, such
as, ventilation and air conditioning are important to ensure that a healthy atmosphere
prevails indoors.
In a work place, where a large number of people work within a confined space, C02
produced due to human respiration gets accumulated in the air, unless there is good
ventilation. Long exposure to higher C02 concentrations can cause human discomfort
and ill health. The C02 concentration, if measured, can be a direct indication of the
efficiency of the ventilation system of the building. This paper presents a detailed study
on how building planning aspects can affect the indoor environment of a building. The
main factor considered was the CO 2 concentration in relation to the ventilation design
of the building. In the study, C02 concentration was measured and related to the
ventilation design of the space in both free running and air conditioned buildings.
The main findings of the study are as follows.
a) Planning aspects of building were found to be very important in minimizing the bad
effects of air pollutants.
b) Provision of openings, based on external wind directions and orientation of the
building were important, to dilute and remove high internal air pollutant
concentrations by natural air currents.
c) Provision of opehings in excess of what is provided in the building regulations was
found to improve the ventilation system in a free running building.
d) The efficient operation of the natural ventilation system was as important as the
ventilation design.
