It is a little-known fact that the air inside your house is dirtier than the air outside it. No matter what you do how many windows you open or whatever this will always be the case. This is true simply because of the amount of hiding places that your house has for dust and other particles, while at the same time having a limited amount of escape routes for the particles.
To go some way towards alleviating this problem, you might want to consider getting an air purifier. This will be especially useful to you if you have allergies or asthma that can be aggravated by dust or other particles such as pollen, as an air purifier can remove most of them from the air for you. If you smoke, you should definitely consider an air purifier, as otherwise all the pollutants in the smoke will build up in your houses air over time, making it very unpleasant to breathe your indoor air.
Air purifiers come in all sorts of different types, each working in different ways. The most popular filter is a kind of fibre mat that goes inside a frame or housing, and can quickly remove 99.97% of pollutants from the air this is known as a high efficiency particulate absorbing filter....