Particulate - Term used for the mixture of solid particles and liquid droplets found in the air. Over 99% of particulate matter is invisible to the naked eye and can easily infiltrate the lungs. On average, every cubic foot of untreated indoor air contains 20 million particles.

Microbe - Includes three major types of organisms: bacteria, protozoa, and fungi/mold. Most of these contaminants rely on a humid and moist environment for growth & survival. Some molds can produce certain chemicals, such as mycotoxins and Volatile Organic Compounds (VOC's).

Gases & Odors - Indoor gases, such as benzene, formaldehyde, and hydrogen sulfide, are released from furniture, carpets, hair sprays, cleaning chemicals, insulation, and pesticides. Gases include VOC's which evaporate into the air easily. Odors are often made up of VOC's or other gases.