Air filtration is a process in which air is run through a filtering system to remove impurities. There are a number of types of air filtration, ranging from filters used to improve air quality inside a home for the benefit of someone with allergies to filtration systems used in biological research facilities to prevent dangerous organisms for being released into the environment. Numerous companies specialize in the installation of air filtration systems and the manufacture of devices that can be used for air filtration.
Air can contain a wide variety of impurities, which may cause health problems or other issues even while remaining invisible to the eye. Dust, particulate matter, and pollen can all trigger allergic responses, for example, and air can carry microbes which will make people sick, along with gases and chemicals which may be linked with illness. Sometimes, air simply smells bad. Air filtration systems are also used for tasks like re-circulating the air in an aircraft.
In an air filtration system, the air must pass through some sort of filter that traps impurities in the air. The design of the filter determines which impurities will be trapped, ranging from soot to viruses. Air may be sent through a series of filters to progressively remove as much as possible, or run through a broad single filter which is designed to trap major impurities. The higher the level of filtration, the more expensive the system tends to be.
One example of an air filtration system is the ductwork used in lab facilities. This system connects to fume hoods and isolation boxes where dangerous materials are handled, sucking the air from these workstations up until the filtration system and trapping dangerous materials before releasing the air into the environment. This type of air filtration system is designed for the safety of the public and the environment. Another example is filtration systems used to create clean rooms with air, which is as clean as possible for the purpose of protecting sick people in hospitals or for creating a controlled environment for research.
In homes and businesses, an air filtration system may be used to improve air quality to keep people more comfortable. In this case, the goal may be to eliminate smells and large particulate matter. The system may continuously re-circulate air through the structure, or pull in air from the outside and filter it before routing it inside. Such systems can also attach to heating and cooling systems to filter the air, which passes through these systems.