Glossary of Terms Air Sanitization – Disinfection


Terms defined, comments in italics


The study of airborne microorganisms, pollen, spores, and seeds especially as agents of infection.

Aerobiology The study of airborne microorganisms, pollen, spores, and seeds especially as agents of infection.
This umbrella term includes the study of indoor air quality.


Converting a liquid or powder into an aerosol; also called atomization and nebulization.

Experimental aerobiology depends on equipment and techniques for safe and effective nebulization of the test microbe.


Particles released into the air from a liquid or solid matrix.

How long such particles remain suspended depends on the combined influence of the nature of the matrix, air turbulence, light, air temperature, and relative humidity.

Air Changes per Hour (ACH)

A metric that tells how many times an HVAC device can fill up the full volume of a room with air.

CDC recommendations:

Air Purification

Filtration method that removes contaminants like allergens or tobacco smoke.

Most air purifiers remove allergens, smoke and VOCs using a mechanical filtration process, without a biological elimination process. Aerobiotix will use the term “purification” since our technology has a mechanical process (HEPA) but is only a part of the whole process.

Airborne Diseases

Diseases that spread through the air which are difficult to control.

Coronavirus, the common cold, Influenza, Chickenpox, Mumps, Measles, Whooping cough, Strep Group A and B, MRSA, Tuberculosis (TB), Respiratory Syncytial Virus (RSV), Pneumonia, Diphtheria (rare now).

Airborne Microorganisms

Airborne microbes are biological airborne contaminants (also know as bioaerosols) like bacteria, viruses or fungi; as well as airborne toxins passed from one victim to the next through the air, without physical contact.

Sources for airborne microorganisms include: humans, pets, plants, plumbing systems, HVAC systems, Mold and resuspension of settled dust (Microbiome, December 2015).

Airborne Spread

Spread of infections via inhalation of an infectious agent.

Such spread requires that respirable particles carrying infectious agents remain suspended in air long enough to be inhaled by a potential host.


Materials derived from plants (eg, pollen), fungi, bacteria or other biologic and nonbiologic sources capable of causing allergic reactions in a host.

Whereas there are synthetic chemicals such as plastics capable of inducing allergic reactions, the emphasis here is on biologic materials only.


Bioaerosols can be defined as fine particles ranging in size and composition that are suspended in the air and considered to be derived from a biological source or to affect a biological target.

Such particles can contain or consist of bacteria, fungi, organic and inorganic particulates, toxins, and viruses.

CARB (California Air Resources Board)

Is the “clean air agency” in the government of California; and under the California EPA.

Tests and certifies various products including air cleaning systems to verify the product does not emit ozone levels that may cause harm.

Clean Air Delivery Rate (CADR)

Is a measure of air purifier performance developed by the American Association of Home Appliance Manufacturers. CADR measures the ability of an air purifier to remove tobacco smoke, pollen and dust from a test room.

Aerobiotix doesn’t measure with CADR because this measurement does not have a biological component. CADR does not measure the actual inactivation of airborne bacteria, viruses or fungi. It just measures inert material being captured by purifier filters. Particles can be removed, but viruses can pass right though undetected by the CADR protocol. Our products are air disinfections units, rather than air purifiers.

Colony-Forming Unit (CFU)

Colonies of airborne bacteria or fungi developed on a culture medium.

Measures the bioload in the air.

Cubic Feet per Minute (CFM)

A measure used in industrial hygiene and ventilation engineering. It describes the rate of flow of air volume into or out of a space. A standard measurement of airflow that indicates how many cubic feet of air pass by a stationary point in one minute.

Example: in a 15’ x 20’ room with 8’ ceilings, the total room volume is 2400 cubic feet. Assuming guidelines of 2 ACH, the room is receiving approximately 80 cubic feet per minute (cfm) of outdoor air.

Disinfection (Air)

In terms of disinfection for air, it is the process of cleaning the air, say with Ultraviolet/HEPA, in order to destroy bacteria, viruses and spores.

Aerobiotix technology disinfects the air as it passes through the Ultraviolet/HEPA unit during the irradication process.


The ability to produce the intended result.

Example: in measuring the effectiveness of ultraviolet light’s ability to eliminate pathogens in the air, it is termed an “efficacy” rate, usually using percentages.

High-Efficiency Particulate Air (HEPA)

HEPA filter is a type of mechanical air filter; it works by forcing air through a fine mesh that traps harmful particles such as pollen, pet dander, dust mites, and tobacco smoke.

Example: a medical grade HEPA filter removes 99.97% of dust, pollen, mold, bacteria and any airborne particles with a size of 0.3 microns. If valuing by MERV ratings, the 99.97% removal rate would be MERV 16.

Independent Testing

The testing of products through an organization or company that is not affiliated with a company that created the products. Therefore no commercial bias occurs.

Also called “third party” testing.

Indoor Air Quality

Quality of the air within buildings and other enclosures, with particular reference to the health and comfort of the occupants.

The overall quality of indoor air is dependent on a mix of a variety of factors that may be site and time sensitive.

Infectious Aerosol

A collection of pathogen-laden particles in the air. Aerosol particles may deposit onto or be inhaled by a susceptible person.

There are over 40 pathogens with the potential to be an aerosol route of transmission.

Infectious Agent

A microbe capable of causing an infection.

The capacity of a microbe to infect a given host depends not only on its biology but also on the general health status of the host and the portal of entry into the host.


A process by which an object is exposed to, for example, Ultraviolet light, to remove and destroy harmful microbes.

The object in this case is the air; the largest surface in indoor environments.

Load and Duration

Referring to testing of pathogens in the air, load is the amount of pathogens and duration is how long pathogens remain in the air.

Can also mean how long it takes for pathogens to be reduced by technology being tested.

Microbial Pathogen

A microbe capable of causing localized or generalized damage to the host.

Please see “Infectious agent.”

Micron Particles

Micron is a unit of length (one millionth of a meter) used in many scientific fields and is particularly used in measuring particles in the air.

Abbreviated as μm.

Minimum Efficiency Reporting Value (MERV)

Developed by the American Society of Heating, Refrigeration and Air Conditioner Engineers (ASHRAE). MERV values vary from 1 to 16.

The higher the MERV value the more efficient the filter will be in trapping airborne particles.


A unit of measurement used to measure length. One nanometer is one billionth of a meter.

Standard measurement for Ultraviolet wave lengths.


Something that follows as a result or consequence.

Example: when testing Aerobiotix technology, outcome refers to the results of reduction of airborne bioload the technology achieves.

Particulate Matter (PM)

The term for a mixture of solid particles and liquid droplets found in the air. Some particles, such as dust, dirt, soot, or smoke, are large or dark enough to be seen with the naked eye. Others are so small they can only be detected using an electron microscope.

Continually in the air where viruses and bacteria will “hitch” a ride.

Pathogen (microbial)

Any microbe capable of causing damage to the host.

Even an otherwise innocuous microbe can become pathogenic depending on the general resistance of the host or the microbe’s entry into normally sterile areas of the body where it can become an opportunistic pathogen.

Peer Reviewed Studies/Publications

A peer-reviewed publication is also sometimes referred to as a scholarly publication. The peer-review process subjects an author’s scholarly work, research, or ideas to the scrutiny of others who are experts in the same field (peers) and is considered necessary to ensure academic scientific quality.

Peer reviewed studies are conducted using the scientific method of testing a hypothesis and documenting the results to reach a valid conclusion. These studies are the most respected types of studies and need to be unbiased to be published.

Photolytic Chamber

An Aerobiotix proprietary process that is an ultraviolet reactor inside the unit, made up of thousands of glass crystals (silicate quartz) and UVC bulbs.

This reactor suspends biologicals like viruses, bacteria and spores that is in the air passing through. It slows down these pathogens and agitates them while being irradiated. This prolongs exposure time to increase irradiation time.


A fine powder produced by certain plants. During the spring, summer, and fall seasons, it is released into the air and picked up by the wind. The wind carries it to other plants so they can make seeds.

Often a cause for allergies.

Single Pass Testing

The test suspension challenging the filter only passes the filter once.

This represents how most filtration occurs in a real world application to achieve the most realistic performance measurements.

Ultraviolet C Radiation (UVC)

Ultraviolet C radiation has wavelengths from 200 to 290 nanometers. Ultraviolet describes light with a wavelength that’s less than visible light, but longer than x-rays. UVC is a germicidal and can be used for disinfection. It works by disrupting the replication process of viruses and destroying the nucleic acid in bacteria.

There are three categories of ultraviolet light wavelengths: UVA, UVB and UVC. UVC is the ultraviolet light wavelength proven to neutralize pathogens. UVC wavelengths are between 200 and 300 nanometers, where 254 nanometers has been proven to be the most effective level of neutralizing pathogens.


Ultraviolet Germicidal Irradiation

Often used interchangeably with ultraviolet technology; utilizing UVC wavelengths to neutralize pathogens.

Viable Particle

A particle that contains one or more living microorganisms.

Example: bacteria, fungi, spores, mold


A virus is a small collection of genetic code, either DNA or RNA, surrounded by a protein coat. A virus cannot replicate alone. Viruses must infect cells and use components of the host cell to make copies of themselves. Often, they kill the host cell in the process, and cause damage to the host organism. Researchers estimate that viruses outnumber bacteria by 10 to 1.

Because viruses don’t have the same components as bacteria, they cannot be killed by antibiotics; only antiviral medications or vaccines can eliminate or reduce the severity of viral diseases, including AIDS, COVID-19, measles and smallpox – once they are inside the body. NIH

Volatile Organic Compounds (VOC)

Volatile organic compounds are gases that are emitted into the air from products or processes. Some are harmful by themselves, including some that cause cancer. In addition, they can react with other gases and form other air pollutants after they are in the air.

Indoor sources of VOC include things like paint, carpeting, cleaners, disinfectants, gasoline, tobacco smoke, glues, etc.

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