Air filter

Air filter is a device composed of fibrous or porous materials which removes solid particulates such as dust, pollen, mold, and bacteria from the air. Air filters are used in applications where air quality is important, notably in building ventilation systems and in engines.

History

The concept of air filtration has been around since the 19th century when John and Charles Dean invented a smoke mask to filter out smoke and dust particles for firefighters. However, the modern air filter wasn't developed until the mid-20th century.

Types of Air Filters

There are several types of air filters, including:

• Mechanical air filters: These filters use synthetic fibers to trap small particles, debris, and dust, among other things. They are commonly used in heating, ventilation, and air conditioning (HVAC) systems to improve indoor air quality.

• Activated carbon filters: These filters use a special form of carbon that has been processed to have tiny, low-volume pores that increase the surface area available for adsorption or chemical reactions.

• Electrostatic air filters: These filters use an electrostatic charge to attract and trap particles. They are typically reusable and must be washed regularly.

• HEPA filters: High Efficiency Particulate Air (HEPA) filters are able to trap 99.97% of airborne particles down to 0.3 microns in size.

Applications

Air filters are used in a variety of applications, including:

• HVAC systems: In homes and offices, air filters are used in HVAC systems to remove particles from air that is to be conditioned.

• Internal combustion engines: In vehicles, air filters are used to remove particles from air that is to be burned in the engine.

• Cleanrooms: In cleanrooms, air filters are used to remove particles from incoming air to create an environment free from dust and other contaminants.

See Also

• Air purifier
• Dust collector
• Filter (chemistry)