It may be difficult to imagine, but houses have lots of dust and selecting the best furnace filter is very important to air quality. Indoor air, according to the U.S. Environmental Protection Agency, is two to five times more polluted than the outdoor air. But the reason most people are not aware about this is because microscopic size dust particles are present in the home - not visible to naked eye. Typically, they are suspended in the air due to their small size and the electrostatic charge that they carry. 99% of dust in the home is made up of the tiniest particles, and these are able to even by-pass the body's system like the nose, and the windpipe. Even the body is designed to filter out only particles greater than 3-5 microns in size and keep them away from the lungs.



A typical house contains dust from pollen, spores, pet dander, lint, bacteria, etc. Even regular home activities like cooking or dusting add to the dust in the air inside the house. Such dust particles results in irritation of eyes and on entering the respiratory system, may cause respiratory disorders, damage to the lungs, or in unique cases, even cancer. For more information regarding furnace filters visit http://www.webproducts.com/Categories.bok?category=Furnace+Filters.

In order to keep the quality of the air inside the home healthy, good quality furnace filters for your furnace unit should be used. There are various types of filters available on the market. These can be disposable, reusable or refillable. They're usually made from materials like fiberglass, metal, man-made or natural fibers. The efficiency of a filter is decided by fiber size, fiber density, airflow rate and particle diameter. Different types of filters available in the market are:

Panel Filter- These types of furnace filters commonly consist of 1? fiberglass filter installed in the ducts. However, these furnace filters are not very effective in removing dust from the air, as its primary function is protection of the internal fan and minimizing dust on the heating coil. These are a very basic filter and can trap only larger particles from the air.

Washable/Reusable Filters- These are meant for extended use, and with regular cleaning and maintenance serve a very long life. Their downside is that it is nearly impossible to get completely cleaned and therefore adds resistance to the airflow. These types of furnace filters are also not very effective in trapping very small particles.

Pleated Filters- These are a modified kind of panel filters that have pleats or folds to increase its surface area. This design change makes it more efficient at trapping dust particles due to increased surface area. However, here too, the furnace filter starts resisting airflow once it starts collecting dust particles and thus should be replaced regularly.

High Efficiency Pleated Filters- These filters have an additional component of electrostatic charge that is designed to capture extremely small particles and various allergens, which make-up 99% of the particulate composition of the air. However, even these should be changed at regular intervals to maintain the air quality, and the airflow. Alternatively, refillable furnace filters are also available in this type.

High Efficiency Particulate Air (HEPA) Filters- These are extended filters that are able to remove sub-micron particles with high efficiency. HEPA filters have corrugated separators that have the core filters folded back and forth over it. This gives strength and also facilitates air passage between the pleats. However, these types of filters are not designed to fit most of the standard furnaces, as they require a separate system that includes a fan and a filter.

The actual filter that is suitable for your house depends on a lot of factors. First of all, it should be compatible with your furnace dimensions. If you live in a high pollution area, you should consider High Efficiency Pleated filters or HEPA filters. These are also recommended if any of the family members have allergies to any form of dust. For other regular purposes, Pleated filters should work fine most of the time. Care should be taken to maintain your furnace filters properly and change them when required. We spend a good part of the day in our homes, so it's important to maintain healthy air inside our house.