Air Cleaner

When it comes to getting pollutants and pathogens out of the air, there are a few different goals and methods. If an overall reduction in the number of particles in the air is the goal, then a simple fibrous filter can work. HEPA and ULPA filters remove a wide variety of particles.

Volatile organic compounds and other harmful chemicals that may be too small to be trapped by a HEPA or ULPA filter can be removed with an activated carbon filter. Air purifiers with carbon filters combine a fibrous filter stage with an activated carbon or charcoal stage to remove both particulate matter and gaseous pollutants.

However, it may also be beneficial to kill or otherwise neutralize pathogens in the air. Air cleaners kill and deactivate bacteria and viruses. Air cleaners use a variety of means to damage microorganisms that are present in untreated air in order to reduce the transmission of airborne pathogens.

Danger is in the air

The air carries microorganisms, spores, and viruses, which can cause a variety of issues for humans. Airborne viral pathogens such as influenza and COVID-19 cause significant human mortality. Bacteria that cause tuberculosis and Staphylococcus aureus infections are serious causes of medical complications and can be transmitted through the air at hospitals.¹

In industrial farming operations, use of air cleaners or air sanitizer machines to reduce the transmission of pathogens can be crucial.² Indoor plant farms that produce products such as hothouse tomatoes or ornamental plants are often vulnerable to airborne transmission of pathogens.³ The controlled temperature and humidity conditions with rows of genetically identical plants give molds and mites the perfect opportunity to run wild. A clean air machine or air sanitizer that kills pathogens may be used to deactivate pathogens.

Killing or otherwise sterilizing the bacterial and viral pathogens isn’t just for hospitals. The benefits of air filtering can be brought home with residential air cleaners.

Methods of cleaning

An air cleaning system involves some method of airflow so that the air in the surrounding environment can be cleaned. Passive systems rely on the natural circulation of air within a space to bring the air into contact with the cleaning method. Active systems use a fan or other means of circulation to pass air through a cleaning chamber where pathogens can be killed or deactivated.

In passive systems, an ultraviolet lamp can be used to kill bacteria and deactivate viruses in air that flows past the lamp. Ultraviolet germicidal irradiation becomes more effective the closer any given volume of air is to the ultraviolet lamp, so active systems which draw air into the UV chamber can treat a larger volume of air.

An air cleaner can also use activated oxygen to disarm pathogens. Activated oxygen reacts with bacteria and viral genetic material and can render them unable to replicate. Since a single bacterium or virus needs to reproduce in order to make people sick, sterilizing the pathogen reduces their ability to cause an infection.