Air filter

An 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.

Types of Air Filters

HEPA Filters

A HEPA filter

High-efficiency particulate air (HEPA) filters are designed to trap at least 99.97% of particles that are 0.3 microns in size. They are commonly used in medical facilities, automobiles, aircraft, and homes.

HVAC Filters

An HVAC air filter

Heating, ventilation, and air conditioning (HVAC) systems use air filters to improve indoor air quality and protect the system from dust and debris. These filters vary in efficiency and are rated by the Minimum Efficiency Reporting Value (MERV).

Engine Air Filters

An engine air filter for an Opel Astra

Engine air filters are used in internal combustion engines to prevent abrasive particulate matter from entering the engine's cylinders, which can cause mechanical wear and oil contamination.

Cabin Air Filters

Cabin air filters are used in vehicles to filter the air that comes into the cabin through the heating, ventilation, and air conditioning system. They help to remove dust, pollen, and other airborne particles.

Functionality

Air filters work by trapping particles in the air as it passes through the filter material. The effectiveness of an air filter is determined by its ability to capture particles of various sizes and its airflow resistance.

Maintenance

Regular maintenance of air filters is crucial to ensure their effectiveness. Dirty or clogged filters can reduce airflow, decrease efficiency, and lead to increased energy consumption or engine wear.

A dirty air filter

Advanced Air Filtration Technologies

Low Temperature Oxidation Catalysts

A low temperature oxidation catalyst

These catalysts are used in conjunction with air filters to remove volatile organic compounds (VOCs) and other pollutants from the air at low temperatures, enhancing air quality.

Related Pages

• Air pollution
• Ventilation (architecture)
• Internal combustion engine
• Particulate matter

Gallery

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  Another view of an engine air filter for an Opel Astra