|Air purifier glossary: Commonly used terms and definitions|
|•CADR: Clean Air
Delivery Rate (CADR) signifies the amount of clean air delivered by an air
purifier. Three numbers are usually listed for each air purifier
(one for tobacco smoke, one for pollen, and one for dust). The higher the
tobacco smoke, pollen and dust numbers, the faster the unit filters the air.
The CADR determines how well an air purifier reduces these pollutants.
•Carbon/Zeolite: Carbon and zeolite are materials used in some air purifiers that remove gases and odors. Both have properties that allow them to absorb gaseous materials and pollutants. Zeolite is a cheaper version and is not nearly as effective as carbon.
•CFM: Cubic feet per minute. The amount of air, in cubic feet, that
flows through a given space in one minute. 1 CFM equals approximately 2 liters
per second (l/s).
•Ozone: A unstable derivative of oxygen, O3, that is formed naturally in the ozone layer from atmospheric oxygen by electric discharge or exposure to ultraviolet radiation. It is a highly reactive oxidizing agent used to deodorize air, purify water, and treat industrial wastes.
•Prefilter: A filter used in many air purifiers that is designed to
capture particles 1 micron in size and larger. Some air purifiers used
activated carbon as their prefilter to remove odors and gases. A prefilter will
extend the life of a HEPA filter.