Pleated Filters Vs Web Filters
Air filters come in a variety of shapes, construction styles and materials. Choosing the best filter for a specific application requires understanding the purpose and types of filters. Learning a few basic facts can take picking the best filter(s) for your situation out of the realm of guesswork into an informed decision.
Function
Air filters remove allergens, dust, pet dander, viruses and other unwanted substances. Air filters improve the long-term functioning of your furnace, vacuum cleaner, air conditioner and car engine.They protect motors from excessive wear by preventing the grit of dust from wearing down the parts. They also provide your home with cleaner air, which promotes lung health. Cleaner air means less frequent cleaning or painting of surfaces in the home. Air filters can improve the shelf-life of perishable foods by removing molds and other bacteria from the environment. The most sensitive air filters can protect from airborne bacteria and radioactive particles.
Types
Filters are made of panels, screens, pleats and felt. Panel filters are made from man-made or natural materials such as wool, rayon or metals. When panels are made from dense materials, they will screen out finer particles than panels made from more open materials. Screen filters are common in dryers and are often made of a fine metal or nylon mesh. Pleated filters are typically made from a specially made paper or fiber that is pushed into a frame with approximately 1-inch pleats with air space of 1/4- to 1/2-inch spaces between pleats. Felt filters are frequently made of wool fibers knit together, then heated so the fibers get very close together.
Benefits
Some panel filters are made to be washed out at regular intervals and used over and over again. The benefit of this type of filter is long-range cost savings.
Throw-away fiberglass furnace filters have an average efficiency rating of 8 percent. Pleated filters have an efficiency rating of 30 to 50 percent. The efficiency rating represents the percentage of the air particles the filter removes. HEPA (high efficiency particulate arrestance) filter technology was developed to reduce radioactive particles from research facilities. HEPA filters, by definition, must remove 99.7 percent of all particles down to 0.3 micron in size.
Other Considerations
Since HEPA filters block such tiny particles that they can easily get clogged by other particles like sawdust unless a pre-filter is used to catch the larger particles first. Because HEPA is known for its effectiveness, some manufacturers use "HEPA-like" or a similar word construction to confuse consumers, so make sure what you're buying.
Use Determines Best Product
Ultimately, the best filter for any given product depends on its use. Consider the size of the particles you want to filter out--the size of the particles most common in your environment. A web filter may be the most appropriate filter as a pre-filter for a pleated filter that takes smaller particles.
