Indoor air pollution is mostly more polluted than outdoor air pollution, yet it receives far less public attention. As we often spend up to 90% of our time indoors (at home, work or at school), exposure to indoor air pollution is damaging our health in a more significant way. That is why the World Health Organisation considers indoor air pollution as one of the main health threats today, and states that around 3% of the global burden of disease is directly attributable to it.
Indoor air pollution is a complex mixture of substances in the air that are potentially very harmful to health. The composition of this indoor air pollution mixture can vary greatly. For instance in a home in a non-urban setting, house dust mite, pollen and mould spores can be a major cause of indoor air pollution. In a new-build home or office, it is mostly the off-gassing fumes from wall paints and insulation, new carpet and furniture that are significantly contributing to the pollution mix. Traffic and industry pollution also play an increasing part in indoor air pollution, especially in urban settings.
The size of the particles found in indoor air pollution range from 100 microns to smaller than 0.01 microns. The heavier particles tend to settle as dust but are easily stirred up again when someone walks through a room or even when a surface is dusted; damp dusting, not dry dusting, is needed to actually remove dust rather than just spread it around. Most carpets are a major reservoir for dust and for every six rooms in a house around 40 pounds of dust is generated in a single year.
The main components of dust which can affect your health indoors are:
From 0.1 microns and smaller, pollution falls into the nanoparticle and molecular size range. Among the major sources of invisible gaseous and chemical pollution are:
Preventing indoor air pollution is sometimes easier than reducing or removing it.
What role does ventilation play in reducing indoor air pollution?
Letting fresh air into the home, and releasing polluted air should be part of your strategy for improving indoor air quality. The exception is going to be if one of the main sources of pollution is coming from the outside – which unfortunately is often the case. We would recommend opening windows after bathing, showering or cooking so that damp and mould don't build up.
An effective air purifier will play an essential part in reducing indoor air pollution in your home or place of work. A mechanical air purifier fitted with a High Efficiency Particulate Air (HEPA) filter can remove over 99.5% of particles down to 0.003 microns in size. Electronic air purifiers rely upon placing electric charges on the particles so they stick to a surface either in the room (ionising air purifier) or inside the machine (electrostatic precipitator). The performance of these air purifiers will significantly vary. To remove gaseous and chemical pollution an absorbent material, such as activated charcoal, will need to be integrated into the air purifier. Otherwise, only particulate pollution will be removed.
What other tips will help cut down indoor air pollution?