Glossary of Mold Terms

ALLERGEN: A substance, such as mold, that can cause an allergic reaction.

ANTIMICROBIAL: Agent that kills microbial growth (i.e., chemical or substance that kills mold or other organisms). See "Biocide" and "Fungicide."

BIOLOGICAL CONTAMINANTS: 1) Living organisms, such as viruses, bacteria, or mold (fungi), 2) the remains of living organisms, or 3) debris from or pieces of dead organisms.  Biological contaminants can be small enough to be inhaled, and may cause many types of health effects including allergic reactions and respiratory disorders.

BIOCIDE: A substance or chemical that kills organisms such as mold.

BUILDING ENVELOPE: Elements of the building, including all external building materials, windows, and walls, that enclose the internal space.

CEILING PLENUM: Space between a suspended ceiling and the floor above that may have mechanical and electrical equipment in it and that is used as part of the air distribution system. The space is usually designed to be under negative pressure.

FUNGI: A separate kingdom comprising living things that are neither animals nor plants. The kingdom Fungi includes molds, yeasts, mushrooms, and puffballs. In this course, the terms fungi and mold are used interchangeably.

FUNGICIDE: A substance or chemical that kills fungi.

HEPA: High efficiency particulate air (filter).

HVAC: Heating, ventilation, and air-conditioning system.

HYPERSENSITIVITY: Great or excessive sensitivity.

HYPERSENSITIVITY PNEUMONITIS: A group of respiratory diseases that cause inflammation of the lung (specifically granulomatous cells). Most forms of hypersensitivity pneumonitis are caused by the inhalation of organic dusts, including molds.

MOLD: A group of organisms that belong to the kingdom Fungi. In this course, the terms fungi and mold are used interchangeably.

mVOC (microbial volatile organic compound): A chemical made by mold that is a gas at room temperature and may have a moldy or musty odor.

MYCOTOXIN: A toxin produced by a mold.

NEGATIVE PRESSURE: A condition that exists when less air is supplied to a space than is exhausted from the space, so the air pressure within that space is less than that in surrounding areas. Under this condition, if an opening exists, air will flow from surrounding areas into the negatively pressurized space.

PLENUM: Air compartment connected to a duct or ducts.

PRESSED WOOD PRODUCTS: A group of materials used in building and furniture construction that are made from wood veneers, particles, or fibers bonded together with an adhesive under heat and pressure.

REMEDIATE: Fix.

SPORE: The means by which molds reproduce. Spores are microscopic. They vary in shape and range from 2 to 100 microns in size. Spores travel in several ways: passively moved by a breeze or water drop, mechanically disturbed (by a person or animal passing by), or actively discharged by the mold (usually under moist conditions or high humidity).

TOXIGENIC: Producing toxic substances.

See also Indoor Air Quality, Glossary of Terms: www.epa.gov/iaq/glossary.html