The probability of immediate reactions to indoor air pollutants depends on many factors. Preexisting medical conditions and age are two important influences or if a person reacts to a pollutant depends on individual sensitivity, which varies tremendously from person to person. Some people can become sensitized to organic pollutants after frequent exposures, and it seems that some people can become sensitized to chemical pollutants as well.
Other health effects may show up either years after exposure has occurred or only after frequent or long periods of exposure. These effects, which include some respiratory diseases, cancer and heart disease, can cause severely debilitating or fatal. We need to improve the indoor air quality in our home even if indications are not noticeable.
It is really hard to identify what applications or periods of exposure are necessary to yield specific health problems. But we all know that pollutants are commonly found in indoor air and the indoor air is responsible for many harmful effects. Individuals also react very differently to exposure to indoor air pollutants. Additional research is required to better understand which health problems follow after exposure to the pollutant concentrations established in homes and which health problems happens from the higher applications that occur for short periods of time.
How Does Outdoor Air Enter a House?
Outdoor air comes in and leaves a house by different ways. Some examples are mechanical ventilation, infiltration and natural ventilation. In newer homes, the aim in construction is to bring the infiltration to near zero. As an illustration, there are different mechanical ventilation devices. In a single room like bathrooms and kitchen we can install outdoor-vented fans that intermittently remove air from that room. Another type of mechanical ventilation is air handling systems that use duct work and fans to constantly remove indoor air and allocate conditioned and filtered outdoor air to considered points all over the house. If outdoor air flows into the house through joints, openings, and cracks in floors, walls, and ceilings, and around doors and windows, this is known as infiltration. If air moves through opened windows and doors it is called natural ventilation. Air temperature differences between indoors and outdoors and also wind creates air movement associated with natural ventilation and infiltration. To determine the air exchange rate we need the rate at which outdoor air exchanges indoor air. The air exchange rate is a small number and pollutant ranks can rise if there is little natural ventilation, infiltration, or mechanical ventilation. This is why we need to open the windows and doors once in a while. We'll be examining this point in more detail later on.
If we want to compare constant outdoor to indoor pollution concentrations, it is necessary to determine the required average time so outdoor pollutants is different from the...