Indoor air pollution is one the most important global environmental problems. It exposes more people to pollutants than outdoor air. There is an average of 500/m3 of suspended particles in a house at Delhi. It may be as high as 10000/ m3 in a smokey house at Nepal. Indoor air pollutants do not diffuse out and are difficult to manage properly. They contribute to chronic lung disease, acute respiratory infection, cancer and adverse pregnancy outcomes. Reducing indoor air pollution can lower the prevalence of pneumonia in susceptible children. The major indoor pollutants are Carbon monoxide, nitrogen dioxide, sulphur dioxide, formaldehyde, asbestos, radon and mineral fibers. They are a result of
• Tobacco smoke
• Cigarettes
• Aerosol spray
• Gas heaters
• Gas cookers
• Carpet adhesives
• Electronic arcing.
Passive smoking can lead to various lung diseases too. Air quality guidelines are enforced these days to control air pollution. Protective green belts between residential and industrial areas are of much use in cutting down the emissions. Height of chimneys is fixed and smoke free zones can be created to alleviate the pollution. Arresters can be developed for removing contaminants. Air disinfection is still in experimental stages to help the human race get through adverse circumstances.