IAQ : INDOOR AIR QUALITY

INDOOR (IQA)

Indoor (IQA) is an index for reporting air quality on a daily basis. It is a measure of how air pollution affects one's health within a short time period. The purpose of the AQI is to help people know how the local air quality impacts their health.

CHEMICALS IN  INDOOR AIR

Ranking air pollutants by risk is difficult because indoor air contains a large number of different substances and because levels vary widely across India. Nonetheless, those that raise highest concern because of the adverse health effects they have caused or have a high potential to cause are:

• carbon monoxide (CO)
• formaldehyde (H₂CO)
• benzene (C₆H₆)
• nitrogen dioxide (NO₂)
• naphthalene (C₁₀H₈).
• xylene (C₈H₁₀)

Environmental tobacco smoke – Tobacco smoking is the primary source of several indoor emissions (benzene, fine and ultrafine particles) and associated health effects. In adults, secondhand tobacco smoke is linked with irritation and coronary heart disease, and it seems to make respiratory symptoms worse. In children, it appears to be linked with sudden death syndrome and middle ear infections.

Radon (Rn) – Radon is a gas that emanates naturally from the ground, particularly in areas where bedrock contains uranium in excess. It can get inside buildings by diffusing through the soil and is a problem in many parts of Europe. Its presence in indoor air can lead to lung cancer.

Lead (Pb) – The use of lead-containing pigments in indoor paints has been banned or restricted. However, some old houses in parts of the EU still have paintwork containing lead. Even low level exposure to lead is harmful for children, for whom the main route of exposure is swallowing dust.

Organophosphate pesticides – These pesticides which are used indoors against insects, are applied to cracks and crevices or present in insect strips. In some studies, they have been shown to affect the development of the nervous system, which raises concern for possible effects on children. Indeed, indoor exposure to these compounds can be high and occurs through inhalation or ingestion due to accumulation on surfaces, including on children’s toys, and in dust. Concentrations in indoor air are unlikely to be high enough to cause short-term effects, but they may contribute considerably to the overall uptake of these pesticides by children.

INDOOR PRODUCTS 

There are many different household consumer products, including detergents, floor care products, furniture and household fabrics, disinfectants, air fresheners, products for laundering, glues, paints, paint strippers and personal care products. These products may emit chemical compounds or particles that can be breathed in, either when the liquids that contain them evaporate, when they are sprayed as aerosols or when candles and incense are burned. Very little is known about the concentrations that these emissions reach in indoor air, or how much they contribute to total exposure. In addition, consumer products, their use and the concentration of emissions from these products in indoor areas.

Indoor air pollution by various consumer products found that many of them emitted volatile and semi-volatile organic compounds (VOCs and SVOCs). Using computer models and assumptions of different products being present in different rooms, children’s rooms were predicted to contain higher concentrations of these compounds than kitchen/family rooms, and halls/utility rooms. Although typical levels were in most cases acceptable, worst case exposures for some of the compounds exceeded accepted limits. The worst emitters of the investigated consumer products were incense and spray paint, printed matter, and electronic equipment .

AQI MONITORING 

Air quality monitoring refers to continuous measurement of specific air pollutants also known as “criteria air pollutants”. Obtained air pollution data together with natural background/trace gas monitoring and stationary source emission monitoring helps to define what kind of air pollution people are exposed to.