What are Respirable Particulates?
What are the sources of Respirable Particulates?
How do these Respirable Particulates effect us?
How can we control them?

What are Respirable Particulates?

A collective group of fine solid particles, aerosols, mist, smoke, dust, fibers and fumes are called Respirable particulates. The main indoor respirable particulates are ETS and fibers.

Sources of Respirable Particulates

The main sources of respirable particulates are outdoor air, tobacco smoke, wood combustion, and other sources. Tobacco smoke contributes to nearly 20 mg / m3 of daily respirable particulate concentration per pack of cigarettes. Presence of smoker increases the concentration of indoors. Sources of indoor concentration of fibers is due to the presence of carpets, curtains, insulation and asbestos.

Health Effects

Respirable particulates such as ETS and Asbestos are classified as class A carcinogens, which is a rating used by the US EPA. ETS causes various heath problems like respiratory irritation like cough, excess phlegm, and wheeze. ETS is particularly harmful to young children and infants whose parents smoke in their presence. It increases the risk of lower respiratory tract. Long-term exposure to asbestos can cause abdominal diseases asbestosis, Mesothelioma and lung cancer.

Control Strategies

Cake filtration is used for high particulate concentration and large volume of gas. Fibrous filters are used for low particulate concentration and low flow rates. Panel filters are most frequently used mechanical filters for removing particles from air. Electrostatic precipitator is the most efficient and widely used, as it removes up to 99% of particles less than 1mm in size. Several methods such as adsorption and absorption can be employed to.

1. "Indoor Air Quality & Control", by A.L Hines, T.K. Gosh, S.K. Loyalka and R.C.Warder, Jr., PTR Prentice Hall (1993).
2. "Indoor Air Pollution - Characterization, Prediction, and Control", by Richard A. Wadden, and Peter A. Scheff, John Wiley & Sons (1983).
3. "Air Sampling Instruments for Evaluation of Atmospheric Contaminants", ACGIH, Cincinnati (1989).

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