Glossary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ALL
Backdrafting
Potentially hazardous condition in which the exhaust from combustion appliances does not properly exit the building. This can be due to a number of factors including a blocked flue or a pressure difference within the home.
BACT -Best Available Control Technology
An emission limitation based on the maximum degree of emission reduction (considering energy, environmental and economic impacts) achievable through application of production processes and available methods, systems and techniques. BACT does not permit emissions in excess of those allowed under any applicable Clean Air Act provisions. Use of the BACT concept is allowable on a case-by-case basis for major new or modified emissions sources in attainment areas and applies to each regulated pollutant.
Bake-out
Process by which a building is heated in an attempt to accelerate VOC emissions from furniture and materials.
Bakeout
A technique for reducing the exposure of occupants to emissions of new construction. The building temperature is raised to a high level (to enhance emissions of volatile compounds from new materials) for several days before occupancy, while running the ventilation system at full capacity to exhaust the emissions.
Balance Point
The outdoor temperature at which a building's heat loss to the environment is equal to internal heat gains from people, lights, and equipment.
BEES
See "Building for Environmental and Economic Sustainability."
Benefit/Cost Analysis
An economic method for assessing the benefits and costs of achieving alternative health-based standards at given levels of health protection.
Benzene
A clear, colorless, highly refractive flammable liquid derived from petroleum and used in or to manufacture a wide variety of chemical products, including DDT, insecticides, and motor fuels. Also called benzine.
Big Five Energy Sources
Coal, oil, natural gas, large-scale hydroelectric, and nuclear power.
Bioaccumulants
Substances that increase in concentration in living organisms as they take in contaminated air, water or food because the substances are very slowly metabolized or excreted.
Bioaerosols
Airborne microbial contaminants, including viruses, bacteria, fungi, algae, and protozoa.
Bioassay
Diverse sets of analytical methodologies, which utilize living organisms - applications range from assessment of water pollutants to screening pharmaceuticals.
Biocide
Product typically used to kill microorganisms.
Biocontaminant
Contaminants that are either life forms (e.g., bacteria) or are derived from living things (e.g., rodent droppings).
Biodegradable
Waste material composed primarily of constituent parts that occur naturally, are able to be decomposed by bacteria or fungi, and are absorbed into the ecosystem. Wood, for example, is biodegradable, while plastics are not.
Biodiversity
A large number and wide range of species of animals, plants, fungi and microorganisms. Ecologically, wide biodiversity is conducive to the development of all species.
Bioengineering
Creation of new organisms with specific attributes through the insertion of the appropriate genetic material into the original organisms genome.
Biological Contamination
Contamination of a building environment caused by bacteria, molds and their spores, pollen, viruses, and other biological materials. It is often linked to poorly designed and maintained HVAC systems. People exposed to biologically contaminated environments may display allergic-type responses or physical symptoms such as coughing, muscle aches and respiratory congestion.
Biological Impoverishment
The loss of variety in the biosphere (even when species have not gone completely extinct).
Biological Oxygen Demand (BOD)
A measure of the amount of oxygen consumed in the biological processes that break down organic matter in water. BOD is used as an indirect measure of the concentration of biologically degradable material present in organic wastes. It usually reflects the amount of oxygen consumed in five days by biological processes breaking down organic waste. BOD can also be used as an indicator of pollutant level, where the greater the BOD, the greater the degree of pollution. Also referred to as "biochemical oxygen demand."
Biological Productivity
Nature's capability to reproduce and regenerate, thereby accumulating biomass.
Biomagnification
The increasing concentration of a substance as it passes into higher trophic levels of a food web. Many bioaccumulants are also biomagnified.
Biomass
Plant matter such as trees, grasses, agricultural crops or other biological material. It can provide a renewable source of electrical power, fuel, or chemical feedstocks.
Biome
A large-scale category that includes many communities of a similar nature.
Bioremediation
The use of bacteria and other small organisms (such as single-celled and multicellular microbes and fungi) to clean up or reduce unwanted concentrations of certain substances: also known as biotreatment.
Biosphere
1. The part of the earth and its atmosphere in which living organisms exist or that is capable of supporting life.
2. The ecosystem composed of the earth and the living organisms inhabiting it.
Black Water
Wastewater from toilets and urinals, which contains pathogens that must be neutralized before the water can be safely reused. After neutralization, black water is typically used for non-potable purposes, such as flushing or irrigation.
Blower Door
A large fan placed in an exterior doorway to pressurize or depressurize a building to determine its air leakage rate expressed in air changes per hour or cubic feet per minute.
BMS
See "Building Management System."
Bottom-Up Approach
The development and encouragement of sustainable uses of biodiversity that provides incentives to save species while also respecting the right of all people to support their families and have a decent quality of life.
Brownfield
Abandoned, idled or underused real property where expansion or redevelopment is complicated by real or perceived environmental contamination.
Building Automation System (BAS)
An integration of digital, electronic, and/or pneumatic controls and devices to provide unattended and automatic operation of buildings systems. Systems may include HVAC, elevators, fire suppression, smoke control, security, lighting, and other subsystems.
Building Control System (BCS)
A system that controls the comfort and safety of a building's assets and environment.
Building Ecology
The physical environment and systems found inside the building.
Building Envelope
The exterior surface of a building's construction - the walls, windows, roof and floor. Also referred to as "building shell."
Building for Environmental and Economic Sustainability (BEES)
Software program developed by the NIST (National Institute of Standards and Technology). It is aimed at designers, builders, and product manufacturers. It provides a way to balance the environmental and economic performance of building products. BEES measures the environmental performance of building products by using an environmental life-cycle assessment approach specified in the latest versions of ISO 14000 draft standards. All stages in the life of a product line are analyzed: raw material acquisition, manufacture, transportation, installation, use, and recycling and waste management.
Economic performance is measured using the ASTM standard life cycle cost method, which covers the costs of initial investment, replacement, operation, maintenance and repair, and disposal. Environmental and economic performance are combined into an overall performance measure using the ASTM standard for Multi-Attribute Decision Analysis. The BEES methodology is being refined and expanded under sponsorship of the EPA's Environmentally Preferable Purchasing Program. BEES currently addresses categories of product choices and is not specific to a type of product.
Building Life Cycle
The amortized annual cost of a building, including capital costs, installation costs, operating costs, maintenance costs and disposal costs discounted over the lifetime of the building.
Building Management and Control System (BMCS)
A BMS and BCS integrated together.
Building Management System (BMS)
A system for centralizing and optimizing the monitoring, operating, and managing of a building. Services may include heating, cooling, ventilation, lighting, security, and energy management.
Building-related Illness (BRI)
Diagnosable illness whose cause and symptoms can be directly attributed to a specific pollutant source within a building (i.e., Legionnaire's disease, hypersensitivity, pneumonitis). Also see "Sick Building Syndrome."
Buildings Reborn
The adaptation of old buildings for uses different from their original purpose.
Built Environment
Structures created by humans (as opposed to the natural environment).
Buoyancy
The tendency of warmer air or smoke to rise because cooler air is denser.
By-product
Material, other than the principal product, generated as a consequence of an industrial process or as a breakdown product in a living system.
