how is polluted air suction made?

how is  polluted air suction made?
 natural ventilation describes the air movement through open windows and doors. ıf used correctly, natural ventilation can help lower indoor air temperatures at times, which can get very hot in homes without air conditioning systems or where power outages or blackouts limit the use of air conditioning or make it impossible to use. natural ventilation can also improve indoor air quality by reducing indoor pollutants. examples of natural ventilation are:
• opening windows and doors
• window shading such as closing shutters
most residential forced air heating and air conditioning systems do not mechanically bring outside air into the home and rely on infiltration and natural ventilation to bring outside air into the home. advanced designs for new homes are beginning to add a mechanical feature that brings outside air into the home through the hvac system. some of these designs include energy efficient heat recovery ventilators to reduce the cost of cooling and heating this air in summer and winter.
 air cleaners
there are many types and sizes of air purifiers on the market, ranging from relatively inexpensive desktop models to sophisticated and expensive whole-home systems. some air purifiers are quite effective at removing particles, while others, including most desktop models, are much less effective. air cleaners are generally not designed to remove gaseous pollutants.

learn more about  air cleaners

the effectiveness of an air cleaner depends on how well it collects pollutants from the indoor air (expressed as a percent efficiency ratio) and how much air it draws from the cleaning or filtering element (expressed in cubic feet per minute). a very efficient collector with a low air circulation rate, nor a cleaner with a high air circulation rate, but a less efficient collector will not be effective. the long-term performance of any air cleaner depends on its maintenance according to the manufacturer's instructions.
ımportance of dirty air absorption in 
another important factor determining the effectiveness of an air cleaner is the strength of the pollutant source. desktop air purifiers, in particular, may not be able to remove enough pollutants from nearby strong sources. people with a sensitivity to certain sources may find that air purifiers are only useful in conjunction with concerted efforts to eliminate the source.