Indoor air pollutants are rated among the top environmental health risks according to the Environmental Protection Agency. Homes which are insulated or have airtight construction may experience less than desired indoor air quality. Inasmuch as insulation stops drafts and saves on energy bills, they can potentially stop fresh air from getting into your home and pollutants from getting to the outside.

When it comes to indoor air quality, you have two options; the first is to allow clean exterior air into your home and the other is to have an air cleaning device that forces pollutants out of your home. When it comes to cleaning air, there are two types of mechanisms you can choose to remove airborne pollutants; mechanical air filters and electronic air cleaners.

Air Filter Ratings

Air filters have porous membranes which allow air to flow through them and in the process trapping the pollen, dust, pet dander, dust mites, and mold spores. The American Society of Heating, Refrigerating, and Air Conditioning Engineers came up with a rating system known as MERV which stands minimum efficiency reporting value. The ratings range from 1 which is the lowest all the way to 20 which is the highest. The ratings reveal three important things:

• The filters ability to remove particles

• The ability of the filter to resist airflow

• The expected operating life of the filter

Types of Filters

In order to choose the best filter for your furnace, it is important to know the types that exist in the market. Below are the top 4 types of filters.

Flat-Paneled Fiberglass Air Filters

These filters have a rating of between one and four and consist of a disposable filter made from layered fiberglass fibers. There is a metal-like grating that supports and reinforces the fiberglass material which helps to prevent the filter from collapsing. These filters are capable of capturing large airborne particles but have a low efficiency for filtering viruses, dust mites and bacteria.

Pleated Media Filters

These have a rating of 5 to 13 and have a larger surface area to help in capturing airborne particles. A medium efficiency pleated filter can filter out small to large particles. Most people confuse these filters with HEPA because at ratings of 7 to 13, they have the same effectiveness.

HEPA Filters

These are the ultimate filters with a rating of 17 to 20. They block elements that are as small as 0.3 microns and filter 99.97% of all particles. The reason homeowners find it difficult to install HEPA filters is because they are quite large and may require a retrofit done by a HVAC professional.

Washable Filters

Unlike the use and discard type, washable filters are more permanent. Thanks to their layers of polypropylene weave, these filters can stop a number of pollutants. On the MERV scale, these filters are rated 1 to 4. The maintenance bit of these filters is slightly difficult and they may attract mold due to the dampness.

Upon a review of the above air filters, the pleated media filters and HEPA filters can greatly enhance your indoor air quality.