Source reduction is attacking particulates at their source. This might involve some drastic measures, such as cutting out smoking and getting rid of pets. These solutions might not always be possible or practical.
Another solution is to dilute the concentration of particulates in the air with cleaner outdoor air. Dilution is desirable because it helps decrease gases given off by carpeting, building materials, and other products.
While some air is continually leaving your home, it may not happen at a very high rate in tightly-constructed homes. To speed up dilution, you can open windows and doors to let in more outdoor air. This, too, is not always practical or possible.
The third solution, filtering the indoor air supply, can take several routes. Almost every home has a basic furnace filter, which prevents the biggest particulates, such as lint, hair and large dust, from getting into the furnace. These filters operate at a cleaning efficiency of about 5% at best (meaning that they remove about 5% of all the particulates in your air).
You can insert an electrostatic filter in your furnace. Made of materials such as polystyrene or polypropylene fibers, these filters have a built-in electrostatic field designed to charge and attract particulates. However, they don't remove as much as an electronic air cleaner. People prefer them because they are less expensive, washable, easier to clean, and are non-electric.
Another type, a media filter, is formed of paper or fiber material on a frame. The pleated fabric is designed to expose much more surface area than a basic filter, and these filters are much thicker. These work in part by straining particulates larger than the spaces between the filter fibers from the air stream.
One of the drawbacks of these filters is that they can cause a pressure drop in your heating-cooling system as the filter gets dirtier, meaning that your furnace must work harder to pull air through the filter and the rest of the system. But an advantage is that they are once again, less expensive than an electronic air cleaner and go a long time between changes. This is great if the unit is in tough to get to area like an attic or crawl space. Easy to install, no electrical wiring, no parts to break.
Another way of treating indoor air problems is with an electronic air cleaner. Electronic air cleaners effectively remove nearly all airborne particulates. Placed in the cold air return duct of your furnace, these units remove up to 95% of particulates from the indoor air supply, greatly improving indoor air quality while helping protect the heating system from the ill effects of dust and dirt, and keeping the home cleaner.
Electronic air cleaners remove airborne particulates that filters can't, including nearly all of such small irritating particles as bacteria, pollen, spores, animal dander, viruses and cooking and cigarette smoke. And they have the lowest pressure drop rating of any filtering system (.08 wc) - while helping keep your heating-cooling investment running as cleanly and efficiently as possible.
