The Air we breathe
Each day we breathe, we fill in our
lungs a mixture of nitrogen, oxygen, water, argon, carbon dioxide and other trace
gases. Approximately we inhale around 14,000 litres (14 m3) of air in
proportion with 26,000 breaths and remain unsure of how much pollutants we
inhale into our bodies. According to an estimate most people live in those most
polluted regions of the world which exist in urban areas, thereby spending 90%
of their time inside buildings, where
a further few percent are found in vehicles and only 6% outdoors. So that
simply refers to the notion that our main breathing environment is the indoor milieu.
Breathing in indoor
environment is generally considered safer than outdoor, where air pollutants are
high NO2 concentrations near roads. The reason is due to various sources of air
pollution, the concentrations of these pollutants inside buildings is lower
than the concentration outside, because the pollutants are deposited to
internal surfaces during the residence time of air in the building. However, this
is not the only reason which prevents inside pollution. There are many
additional factors which do not sustain pollutants inside buildings and after
considering the same reduced air turnover, protects us from external pollutants.
Another reason that does not allow external pollution is that we are already involved
in sustaining through the same gases and particles that penetrate in from the
outside, but a whole range of new pollutants that only increase to significant
concentrations in the confines of the indoor environment. Furthermore we cannot
ignore cooking fumes, tobacco smoke, heating, lighting, aerosol sprays,
micro-organisms, moulds and fungi.
Buildings ventilation helps
in controlling the rate of exchange at which there might be a threat of
swapping inside air with that of outside air. The ventilation not only helps in
the ingress of outside pollutants into the building, but it works in such a
manner in which the ratio of release of indoor pollutants from the building is
increased. Therefore a controlled ventilation of building not only saves energy
costs, but it fosters maintaining comfort with air quality.
Solid fuel combustion takes
place in many developed countries where most commonly
found traditional fuels are wood, charcoal, agricultural residues and animal
wastes. These fuels serve as the source of meeting energy needs to 2 billion
people, and 25% of the total energy is consumed in developed countries. Tobacco
consumption is responsible for producing most of the gaseous and particulate air pollutants where not only a
smoker is subjected to the environment but a non-smoker
is also reluctantly breathes in the same environment. A single smoke upholds
the inhaling of more than 4500 compounds of which, 50 are known to be
carcinogenic. Categorized into mainstream (MTS), sidestream (STS) and
environmental (ETS) tobacco smoke, inhaling ETS is known by the name 'passive
smoking' which can induce severe effects ranging from eye watering, continuous
coughing and allergic reactions which can form lung cancer. However there are
many other reactions to the ETS like slow lung functioning in children, growth
rate of asthma and pneumonia. A study revealed that around 17% of lung cancers dwell
among non-smokers which may be attributed to ETS exposure during childhood. Every
year in UK, 1, 00,000 people loose their lives through smoking-related illness,
and thousand others become the victims of passive smoking.
