Air Purifiers for Pathogens

Air Purifiers for Pathogens at

Health Risks of Pathogens (viruses, microbes, bacteria, germs)

Pathogens are infectious microorganisms or agents such as viruses (including coronaviruses), bacteria, microbes, germs, fungus (fungi). While the vast majority of bacteria are harmless or even beneficial to humans, some pathogenic bacteria, microbes and viruses are highly prone to cause globally significant infectious diseases such as tuberculosis, pneumonia, SARS and now COVID-19 (caused by SARS-CoV-2 coronavirus).
The other infectious diseases caused by viral pathogens include:

  • influenza
  • smallpox
  • mumps
  • measles
  • chickenpox
  • ebola
  • rubella
  • tetanus
  • typhoid fever
  • diphtheria
  • meningitis
  • anthrax

Although many pathogenic microorganisms primarily spread through a direct contact, due to a very small size and weight they can easily become airborne when the infected person spreads the pathogens through breathing or respiratory droplets expelled from the mouth and nose while sneezing and coughing.

Size of Pathogens:

  • Bacteria: 1 - 5 micron
  • Fungi: 1 - 40 micron
  • Viruses: 0.02 - 0.3 micron
  • SARS-CoV-2: ~ 0.12 micron

Pathogen Remediation

While pathogens are constantly present in the air, their type and concentration can be especially dangerous for children, individuals who have chronic asthma or other respiratory impairments, or those with preexisting respiratory ailments such as COPD, bronchitis, emphysema.
Effective removal of airborne pathogens out of the air can help significantly reduce the occurrence of infectious diseases caused by pathogenic microbes, bacteria and viruses and for these groups of people may become a life saving requirement.

There are few ways to suppress (kill) pathogens by subjecting them to:

  • Chemicals (bleach, antibiotics)
  • Ultraviolet light
  • High temperature
  • Mechanical air filtration
  • Plasma (Ionization)

Exposure to Chemicals (bleach, antibiotics)

Many chemicals commonly named "bleach" containing chlorine based (sodium hypochlorite), peroxide based (hydrogen peroxide) and others are known to have a broad spectrum of bactericidal (anti-bacterial) properties and, therefore can be effectively used for disinfecting and sterilizing the surfaces and control viruses, bacteria, microbes in places where sterile conditions are required. The effectiveness of bleaches is attributed to their chemical reactivity against organic compounds, including protein. They irreversibly destroy many proteins, which makes them extremely versatile disinfectants.
The antibiotics is the most common method of killing bacteria, microbes, viruses. The antibiotics work by destroying the bacteria cell wall, which leads to expulsion of pathogen's DNA, inability of pathogens to produce proteins and eventually death. The antibiotics can be added into the air using vaporizers or humidifiers with medicine cup. Unfortunately, the recent studies show the emergence and spreading of "superbugs" which develop high level of resistance to selective inhibitory or toxic actions of antibiotics, making them ineffective.

Exposure to UV Light

The Ultraviolet (UV) light (Germicidal UV light especially) is the fastest and most effective way to disinfect and sterilize the air from airborne pathogens. The Germicidal UV bulb produces the ultraviolet light (UVC) with a specific wavelength of 253.7 nm (nanometer). The exposure of pathogens to the UV light of this wavelength destroys the Thymine amino acid in pathogen's DNA, leading to pathogen's inability to produce protein and resulting in death.
The sterilization power of Germicidal UV light is about 1,600 times of a direct sunlight, and therefore is extremely lethal to most airborne pathogens - viruses, bacteria, microbes.
Multiple tests show the utmost effectiveness of Germicidal UV bulb in fast and thorough sterilization of the air from airborne pathogens.

Below is the Pathogen Reduction Rate for Germicidal UV Bulb.

Pathogen TypePathogensRate of Reduction
BacteriaEscherichia Coli (E.Coli)> 99.99%
Staphylococcus albus> 99.99%
Streptococcus> 99.00%
Mold, FungusPenicillium Citrinum > 98.00%
Aspergillus Niger> 97.8%
VirusMS2 Viral Stimulant> 98.82%

Exposure to High Temperature

Exposure to high temperature is another common method of deactivating pathogens and antigens. However, it is only applicable to killing pathogens attached to the surface of the objects required sterilization, and hence do nothing with the airborne pathogens, unless the entire volume of air is heated to high temperature, at which pathogens' proteins are destroyed.    

Mechanical Air Filtration

True HEPA filter has a guaranteed filtration efficiency of over 99.97% in trapping all solid sub-micron airborne particulates as small as down to 0.3 micron in size. This size range includes all airborne bacteria, microbes, fungi and larger size viruses. Trapped in the air purifier's True HEPA filter, pathogens are exposed to the constant air rush, which deprives them of moisture and eventually making them to die of dehydration. 
The higher efficiency particle filters such as, 99.99% @ 0.3 micron efficiency Super HEPA or 99.999% @ 0.1 micron efficiency ULPA filters can be more effective in trapping sub-micron viruses. However, tighter particulate filters, especially  ULPA filter, may reduce the air flow and a number of air changes per hour (ACH), resulting in a lower overall performance due to a higher back pressure from a more dense filter media. Therefore, it is essential that the air filtration system of air purifiers for airborne pathogen control contains large and perfectly sealed True HEPA, Super HEPA or ULPA filter.

Plasma Ionization

In the early 2000s SHARP corporation developed and patented an advanced air cleaning technology called Plasmacluster Ion (PCI).
This innovative technology replicates Nature's Own air cleaning process that purifies air in the Earth's atmosphere by producing the balanced shower of positive and negative ions from water vapors in the air.
The ions are dispersed throughout the entire room where they actively seek, attack and deactivate airborne pathogens: germs, bacteria, viruses, mold spores, fungi, etc. Plasmacluster Ion technology also helps neutralize chemicals and reduce allergens and dust in the air.
The Sharp's Exclusive Plasmacluster Ion technology has clinically proven effective in significantly reducing the airborne pathogens such as:

Below is the Plasmacluster Ion Performance Test Results on Pathogens.

Pathogen TypePathogensRate of Reduction
Staphylococcus Epidermis89.7%
Serratia Marsescens85.6%
Mold, FungusPenicillium Citrinum87.7%
Aspergillus Niger85.8%
VirusMS2 Viral Stimulant90.3%

The series of experiments conducted by testing institute in Japan demonstrates that Sharp's Plasmacluster Ion technology (PCI) has the ability to reduce mold, fungus by 90% in just one hour.

Removal of Airborne Pathogens

In view of the above, the most efficient air purifiers for Airborne Pathogens Control should meet few requirements.

1. The air filtration system should include large and perfectly sealed particle filter: True HEPA, Super HEPA or ULPA.
While all air purifiers offered in this page are equipped with large True HEPA filters, two of them AirPura I600 and Amaircare 3000 employ the oversize True HEPA filter each containing a whopping 100 sq. ft. of medical grade True HEPA filter.

2. Germicidal UV bulb most likely is a single most effective option that can significantly boost the air purifier's ability to sterilize the air from airborne pathogens quickly and effectively.
AirPura UV600, AirPura P600AirPura P600 Plus air purifier models all are equipped with high-output Germicidal UV bulb, making them the strongest contenders in the category of the most efficient air purifiers for Airborne Pathogens Control.

3. Sharp FP-F50UW, Sharp FP-F60UWSharp KC-850U and Sharp KC-860U all are equipped with Sharp's exclusive proprietary Plasmacluster Ion generators, and therefore are strong contenders in the category of best air purifiers for Airborne Pathogens Control.

Recommended Air Purifiers for Pathogens

Home and Office Use under 700 sq. ft.

Home and Office Use under 2000 sq. ft.

Air Purifier ModelHEPA Filter, sq. ft.Sterilization mechanismAir Flow Rate, cfm
Airpura UV60040Germicidal UV Bulb560
Airpura P60040Germicidal UV Bulb560
Sharp KC-860U
20Plasmacluster Ion300
Sharp FP-F60UW17Plasmacluster Ion260

Commercial and Business Use over 3000 sq. ft.

Air Purifier ModelHEPA Filter, sq. ft.Carbon Filter, lbs.Air Flow Rate, cfm
Amaircare AirWash MultiPro BOSS 100 x 26.5 lbs. VOC Canister x 22500
Amaircare 7500 Cart
100 x 26.5 lbs. VOC Canister x 21400
Amaircare 6000V Cart1006.5 lbs. VOC Canister800
Amaircare AirWash MultiPro805.5 lbs. VOC Canister1300

Air Purifiers for Pathogens - view all