Air pollution- indoor or outdoor?

All of us are very familiar with air pollution and in a country like India which is teeming with industrialization and rapid urbanization, air pollution is evident everywhere. When we think of air pollution, the first thing that often strikes us is the vehicular pollution and industrial exhausts. But seldom do we know that air pollution could also occur inside closed rooms, commonly termed as ‘indoor air pollution’. The indoor air pollution is influenced by various factors namely, the location and the type of construction of the building, source of pollution, number of persons exposed and the duration of exposure. Let us look at these factors one by one-

1. Location and type of construction: Air pollution is linked with the engineering techniques involved with the construction of buildings.

An ill ventilated house, without adequate windows, cross ventilation, etc is at a major risk for air pollution. To ensure this is ruled out, there are several construction norms by which it is advisable to abide. For example, a window should be within a height of atleast 3 feet from the floor. The window area should be equal to or more than one-fifth of the floor area. Windows and doors together should make up two-fifths of the floor area. It is important to have cross ventilation to provide free flow of air.

Presence of exhaust ventilation is another important aspect of the construction. Any room in which hot air is generated should be equipped with the exhaust ventilation to remove the hot air, especially in kitchen, industrial sections, washrooms, etc.

Moreover, these are days of modern constructions false ceilings are much in vogue for attractive purposes. When such ceilings are made, compromise is made on the height of the ceiling. It is advisable that the height of the ceiling is maintained at least 8 feet from the floor. This will help in ensuring adequate ventilation and airflow.

2. Source of pollution: There are several sources of air pollution depending on the type of activity. In urban areas, the indoor air pollution is often a result of ill ventilated rooms, use of modern air exchange mechanisms like air conditioners. In rural areas and in urban slums, the sources of indoor air pollution are due to the use of biomass fuels like coal, wood, charcoal, dung, etc,. In all the indoor air pollutants include benzenes, formaldehyde, poly aromatic hydrocarbons, carbon monoxide and particulate matter.

3. Exposure status of the individuals: However, the number of persons exposed to the pollutants and the duration of exposure also determine the effects of indoor air pollution. Also, the vulnerability of the individuals, namely children, history of asthma and wheezing, elderly, etc have higher risks of diseases due to indoor air pollution.

Health hazards of indoor air pollution include-

* Respiratory illnesses like bronchial asthma

* Neurological problems like depression

* Cataracts

* Adverse pregnancy outcomes

How do we prevent this?

While a major part of outdoor air pollution needs to be tackled by formulating adequate policies and government interventions, indoor air pollution could be tackled by making individual efforts with respect to choice of appropriate cooking fuel, designing houses and buildings appropriately, etc. In the current era where modern technologies are used for constructions, small measures like the ones stated above will help in the long run to render houses and buildings a healthier place.