Air Filters

Air Filters - Home Filtration Systems

Air filters are made in several designs. One of these designs is the fibrous filter. This filter is made with fibers running vertical to the airflow direction. The porosity is high due to the construction of the design. The smallest fibers are submicrometers and the largest are 100 mm. Plastic, glass, and wood make up the majority of fiber content. Fibrous filters offer a velocity of about 10 cm.

Porous filters are another type of air filter designs. These filters have less porosity than the fibrous filters with a porosity level of 50 percent to 90 percent compared to 70 percent to 99 percent for fibrous. The pore structure is complex causing the gas inside to follow an irregular path. The efficiency of porous filters is high. The materials for this type of filter include polyvinyl chloride, cellulose esters, Teflon, sintered metals, and other types of plastics.

Ways to Clear the Air
Allergies and allergy-related illness is at an all-time high. More pollution is getting into the air being circulated in the home. Studies have shown that there are more pollutants inside the home than outside the home. This makes perfect sense when you consider that the inside air is circulated repeatedly. If it is not cleaned or purified during the recirculation process, the pollutants will continue to multiply. Making the right choice in air filters is essential to having clean air.

The most common disposable air filters are fiberglass or polyester, one inch thick, and designed to be replaced monthly. This type of filter is mostly for protecting the heater and air conditioner from becoming filled with harmful particles. It is not very useful for removing small pollutant particles from the air. The washable or reusable filter offers about the same protection for airborne particles. Check the label to see the manufacturer's rating for air purification.

More Designs for Air Filters
To find air filters designed to capture small particles, the flat or pleated filters made of polyester or cotton are the better choice. They are denser than fiberglass. These are one-inch filters that will need changing four to six times a year. The deep-pleated filters are more efficient in reducing the air pollutants. They last longer than the thinner filters. The thicker filters require systems specifically designed for the five or six inches needed for the filter.

The permanently charged, pleated electrostatic filter is even more efficient due to the design to capture the tiniest particles. The electrostatic charge holds particles that would otherwise escape. The use of the combination of pleated membranes in the filter and the electrostatic charge is highly effective in cleaning the indoor air.

Air Filters - Carbon and HEPA Filters

Air filters are used for purifying the air inside a home or building. The type of filter for optimal contaminant capture will depend on the amount of space to be cleaned and the offending particulates. Circulating fresh outside air is the method of choice; however, many homes and businesses are not located in an environment offering unpolluted air. Industrial pollution, exhaust fumes, pollen, or other particulates are resident in the air most of us inhale.

With all the pollutants in the outdoor air, the indoor air is even worse. This is due in part to the fact that the indoor air is circulated repeatedly with no refreshing. If it is possible, open a window or use an exhaust fan to remove the stale air from inside the home every few days. This will help rid the air of stale odors and some contaminants. It will not cleanse the air of bacteria, mold, and mildew. Special filters are required to capture and destroy some infiltrates.

Air Filters Provide Relief
In spite of the effort to clean the inside air by refreshing with the outside air, many people have serious allergies to household air. Allergy symptoms are a problem for millions of people. An allergen is something the immune system determines is a foreign substance and should not be in the body. The body's response is an allergic reaction to the pollutant.

Many types of allergens affect people in different degrees. Allergic reactions to chemicals, medications, and foods are easy to see and identify. Reactions to inhalants are more difficult to define. Pollen, dust, smoke, and perfume can trigger a major response from someone with sensitivity to the particulate. Sometimes it takes a trip to the allergist for allergy screening to find everything that is active in causing an allergic response.

One of the first lines of defense for indoor allergies is to purify the air. This can be done by either a whole house filtering system or an individual room unit. The whole house system utilizes the central heating and air conditioning unit of the home. All units have at least a basic filter to prevent massive amounts of dust and particles collecting on the operating system. The basic filter is often not sufficient to eliminate all of the particulates in the air.