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Is the air in your home safe?
by Martyn Overy - Saturday, 5 July 2003, 11:56 AM
So, you think you are safe breathing the air indoors, compared with the air outdoors? Think again!

Recent scientific evidence indicates that the air you breathe indoors can be more seriously polluted than the air outdoors!

Our homes and workplaces can be more seriously polluted than the outdoor air in cities. People tend to spend so much time indoors so that the effects of the pollution can become significant, and has a cumulative effect on health. The most susceptible members of the community are the young, the elderly, the chronically ill, and anyone who suffers from respiratory or cardiovascular problems.

What are the origins of indoor pollution?

Airborne particles arise from a variety of sources. Poor ventilation increases the concentration of these pollutants. The sources of pollutants include include the burning of oil, gas, coal, and wood. Building materials and furnishings also contribute, as does the smoking of tobacco. Other sources include furniture made of pressed wood chippings, household cleaning products, and central heating and cooling systems. Some sources originate from outside, and these include radon and pesticides.

Some sources emit pollutants continuously. Building materials, common household produces bought in the supermarket, and the furnishings within your home all release particles into the air. Other sources emit pollutants whenever they are used, such as poorly adjusted stoves and furnaces, solvents used in cleaning and decorating, smoking, and the use of cleaning materials. The amount of time these pollutants remain in the air depends on a number of factors, such as temperature and ventilation, and humidity, and the original quality of the pollutant that has been emitted.

How can we reduce indoor pollution?

So, what strategies can be used to reduce the amount of pollutants within your home, or place of work?

1. Target the source of pollution

Once the source of pollution has been identified, then try to eliminate it. Removal of materials can, however require specialist advice and assistance. If they cannot be removed, then they can be sealed to prevent further emissions. Safety checks on all domesic applicances, especially gas fires can prevent deadly carbon monoxide emissions.

2. Improve ventilation!

It cannot be emphasised enough that the extent of pollution is severely increased by poor ventilation. Air needs to be removed, and replaced with fresh air from outdoors, if the concentration of pollutants is to be reduced. In many cases opening an external window can bring drastic reductions in concentration. Installing ventilation fans or even an air conditioner can all assist in the reduction of the concentration of toxic materials within the air.

In the case of activities which release large quantities of gases and particles in the air, such as painting and decorating, it is important to increase the ventilation by greater amounts, by opening ---- and windows, to increase the rate at which the polluted ar is removed from the building.

3. Use Air Cleaners.

There is a wide range of air cleaners and conditioners available. Some cleaners do not remove a high percentage of airborne particles. Many will simply not remove pollutants in the form of gases. Some cleaners will effectively remove most contaminants in the air. They have effective systems which can filter microscopic particles from the air. Some HEPA systems combine with an ultraviolet light source to virtually eliminate airborne infectious microbes, viruses, bacteria and mold spores. Some air filter systems claim to remove 99.99% of micro-organisms reaching the machine with 85% spore count reduction in room, and destroy micro-organisms less than 1 micron.

However, for most air pollution problems in the home, the most effective method is to remove the source of the pollutant, rather than to filter the contaminants from the air. If this cannot be done, then a combination of three strategies will usually have significant benefits for the health of the occupiers of the buildings.

Further information:

Indoor Air Quality

Indoor Air Quality Publications (US)

Indoor Air Quality (US Dept of Labor)