Albedo – the ratio of the reflected solar energy to the incoming solar energy over wavelengths of approximately 0.3 to 2.5 micrometers.

Alternative Fuel Vehicles (AFVs) – Vehicles that use low-polluting, non-gas fuels, such as electricity, hydrogen, propane or compressed natural gas, liquid gas, methanol, and ethanol.

Biomass – The use of chemicals or physical water treatments to inhibit bacterial growth in cooling towers.

Blackwater – There is not a sole definition, but is to be considered wastewater from toilets and urinals.

Carbon Footprint – “A total set of GHG (GreenHouse Gas) emissions caused directly and indirectly by an individual, organisation, event or product” (UK Carbon Trust 2008). Once the size of the footprint is calculated, a strategy can be designed to mitigate or eliminate it.

Carpool – An arragement in which two or more people share a vehicle for transportation.

Chemical Runoff – Water that transports chemicals from the building landscape, as well as surrounding streets and parking lots, to rivers and lakes. Runoff chemicals may include gas, oil, antifreeze and salts.

Chloroflurocarbons (CFCs) – Hydrocarbons used as refrigerants in HVAC equipment and cause ozone depletion.

Climate Change – Refers to any significant change in measures of climate lasting for an extended period.

Composting Toilet System – Dry plumbing fixtures that contain and treat human waste via microbiological processes.

Concentrate – A product that must be diluted at least eight parts by volume water prior to its intended use (Green Seal 37)

Construction Indoor Air Quality (IAQ) Management Plan – Measures to minimize contamination in a specific project building during construction and describes procedures to flush the building of contaminants prior to occupancy.

Conventional Irrigation – Refers to the most common irrigation system used in the region where the building is located. A conventional irrigation system commonly uses pressure to deliver water and distributes it through sprinkler heads above the ground.

Cooling Tower – A piece of equipment that uses water to regulate air temperature in a facility by absorbing heat from air-conditioning systems or cooling down hot equipment.

Daylight Factor – The ratio of exterior illumination to interior illumination, expressed as a percentage. The variables used to determine the daylight factor include the floor area, window area, window geometry, visible transmittance (Tvis), and window height.

Daylighting – The controlled admission of natural light into a space through glazing to reduce or eliminate electric lighting. Daylighting creates a stimulating and productive environment for building occupants.

Drip Irrigation – A high-efficiency method in which water is delivered at low pressure through buried mains and submains. From the submains, water is distributed to the soil from a network of perforated tubes or emitters. Drip irrigation is a type of microirrigation.

Ecological Restoration – The process of assisting in the recovery and management of ecological integrity.

Emissivity – The ratio of the radiation emitted by a surface to the radiation emitted by a black body at the same temperature.

ENERGY STAR rating – A measure of the building’s performance compared with buildings with similar characteristics, as determined by use of the ENERGY STAR Portfolio Manager. A score of 50 represents average building performance.

Environmental Tobacco Smoke (ETS) – Consists of airborne particle emitted both directly from cigarettes, pipes, and cigars and indirectly, as exhaled by smokers.

Erosion – The process by which the materials of Earth’s surface are loosened, dissolved, or worn away and transported by natural agents.

Exhaust Air – The air removed from a space and discharged outside the building by means of mechanical or natural ventilation systems.

Existing Building Commissioning – Involves developing a building operating plan that identifies current building operating requirements and needs, conducting tests to determine whether the building and fundamental systems are performing optimally in accordance with the plan, and making any necessary repairs or changes.

Evapotranspiration – Water lost through transpiration through plants plus water evaporated from the soil.

Fuel-Efficient Vehicles – Vehicles that have achieved a minimum green score of 40 on the American Council for an Energy Efficient Economy annual vehicle-rating guide.

Geothermal Energy – Electricity generated by converting hot water or steam from within the Earth.

Geothermal Heating Systems – A system that uses pipes to transfer heat from underground for heating, cooling and hot water. The systems retrieves heat from the Earth during cool months and returns heat in summer months.

Glare – Any excessively bright source of light within the visual field that creates discomfort or loss of visibility.

Gray Water – defined by the Uniform Plumbing Code (UPC) “untreated household waste water which has not come into contact with toilet waste. Gray water includes used water from bathtubs, showers, bathroom wash basins, and water from clothes-washer and laundry tubs. It shall not include waste water from kitchen sinks or dishwashers.

Green Cleaning – Using cleaning products and practices that have less environmental impact than conventional products and practices.

Halons – Substances used in fire-suppression systems and fire extinguishers. These substances deplete the stratospheric ozone layer.

Hardscape – Inanimate elements of the building landscaping, including pavement, roadways, stone walls, concrete paths and sidewalks, and concrete, brick, or tile patios.

Heat Island Effect – Refers to the absorption of heat by hardscapes, such as dark, nonreflective pavement and buildings, and its radiation to surrounding areas. Particularly in urban area, other sources may include vehicle exhaust, air-conditioners, and street equipment; reduced airflow from tall buildings and narrow streets exacerbates the effect.

Hydrochlorofluorocarbons (HCFCs) – Refrigerants that are used in building equipment and cause depletion of the stratospheric ozone layer, but they are less damaging than CFCs.

Hydrofluorocarbons (HFCs) – Refrigerants that do not deplete the stratospheric ozone layer buy may have high global warming potential and thus are not environmentally benign.

Hydro Energy – Electricity produced from the downhill flow of water from rivers or lakes.

Hydrology – Address water occurrence, distribution, movement and balances in an ecosystem.

Hypermiling (the Green word of the year) – attempting to maximize gas mileage by making fuel-conserving adjustments to one’s car and one’s driving technique, according to Wayne Gerdes, the person who coined the phrase. Try to exceed the EPA gas mileage limits. How? turn off your a/c and radio, do not accelerate fast, do not stop too quick (unless you must), shut down at long lights, practice being conservative, anything you feel will help you save gas (money), reduce emissions and go green.

Imperviousness – Resistance to penetration by a liquid and is calculated as the percentage of area covered by a paving system that does not allow moisture to soak into the ground.

Impervious Surfaces – Promote runoff of precipitation instead of infiltration into the subsurface. The imperviousness or degree of runoff potential can be estimated for different surface materials.

Incinerator – A furnace or container for burning waste materials.

Indoor Air Quality (IAQ) – The nature of air that affects the health and well-being of building occupants.

Integrated Pest Management (IPM) – The coordinated use of knowledge about pests, the environment, and pest prevention and control methods to prevent unacceptable levels of pest infestation and damage by the most economical means while minimizing hazards to people, property, and the environment.

Invasive plants – Both indigenous and exotic species that are characteristically adaptable and aggressive, have a high reproductive capacity, and tend to overrun an area. Collectively, they are one of the great threats to biodiversity and ecosystem stability.

Lamp Life – The useful operating life of lamps.

Landfills – Waste disposal sites for solid waste from human activities.

LEED Accredited Professionals (AP) – Individuals who have successfully completed the LEED professional accreditation exam.

Legionella – A waterborne bacterium that causes Legionnaire’s disease. It grows in slow-moving or still warm water and can be found in plumbing, showerheads, and water storage tanks. Outbreaks or Legionella pneumonia have been attributed to evaporative condensers and cooling towers.

Light Pollution – Waste light from building sites that produces glare, is directed upward to the sky, or is directed off the site. Waste light does not increase nighttime safety, utility, or security and needlessly consumes energy and natural resources.

Low-Emitting Vehicles – Vehicles classified as zero-emission vehicles (ZEVs) by the California Air Resources Board.

Lumen – A unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of one candle intensity.

Mass Transit – Movement of large groups of persons in a single vehicle, such as a bus or train car.

Material Safety Data Sheets (MSDS) – Contain product information on chemicals, chemical compounds, and chemical mixtures. MSDSs can also include instructions for the safe handling, storage, and disposal of products.

Methylmercury – Any of various toxic compounds of mercury containing the complex CH3Hg; it often occurs in pollutants and bioaccumulates in living organisms, especially in higher levels of a food chain.

Microclimate Factor (kmc) – A coefficient used in calculating the landscape coefficient; it adjusts the Evapotranspiration Rate to reflect the climate of the immediate area.

Microirrigation – Involves irrigation systems with small sprinklers and microjets or drippers designed to apply small volumes of water. The sprinklers and microjets are installed within a few centimeters of the ground; drippers are laid on or below the grade.

Minimum Efficiency Reporting Value (MERV) – A filter rating established by ASHRAE, ranges from 1-16.

Native Vegetation – Plants indigenous to a locality and not considered invasive. Require limited irrigation, limited maintenance and habitat value.

Natural Areas – Native or adaptive vegetation or other ecologically appropriate features.

Natural Ventilation – Ventilation provided by thermal, wind, or diffusion effects through doors, windows, or other intentional openings in the building.

Net Present Value – The total discounted value of all cash inflows and outflows from a project or investment.

Nonpotable Water – Water that does not meet EPA’s drinking water standards, and therefore, is not suitable for human consumption.

Perviousness – The percentage of area covered by a paving system that is open and allows moisture to soak into the earth below the paving system.

Photovoltaic or Solar Energy – Electricity from photovoltaic cells that convert the energy into electricity.

Picogram – One trillionth of a gram.

Picograms per lumen-hour – A measure of the amount of mercury in a lamp per unit of light delivered over its useful life.

Pollutants – Emissions of carbon dioxide (CO2) sulfur dioxide (SO2), nitrogen oxides (NOx), mercury (Hg), small particulates (PM2.5) and large particulates (PM10).

Postconsumer content – The percentage of material in a product that is recycled from consumer waste.

Postconsumer fiber – Paper, paperboard, and fibrous wastes that are collected from municipal solid wast streams.

Post-consumer material – Recycled from consumer waste.

Potable Water – Water suitable for drinking that meets or exceeds EPA drinking water standards; it is supplied from wells or municipal water systems.

Preventive Maintenance – Routinely scheduled equipment inspection, cleaning, and repair conducted to detect and prevent equipment failure and keep materials and systems in working oder.

Process Water – Water used for industrial processes and building systems, such as cooling towers, boilers, and chillers.

Rapidly Renewable Materials – Agricultural products, both fiber and animal, that take 10 years or less to grow or raise and can be harvested in an ongoing and sustainable fashion.

Recirculated Air – Air removed from a space and reused as supply air, delivered by mechanical or natural ventilation.

Reclaimed Water – Wastewater that has been treated and purified for reuse.

Recommissioning – Applies to buildings that were previously commissioned as part of new construction or retrocommissioning. recommissioning involves periodic conducting of the original commissioning tests from the commissioning or retrocommissioning process to ensure that the original results are maintained over time.

Recycling – The collection, reprocessing, marketing, and use of materials that were diverted or recovered from the solid waste stream.

Refrigerants – The working fluids of refrigeration cycles that absorb heat from a reservoir at low temperatures and reject heat at higher temperatures.

Renewable Energy – Energy from sources that are not depleted when used. This includes energy from the sun, wind, and small hydropower. Ways to capture energy from the sun include photovoltaic, thermal solar energy systems, and bioenergy. One issue with bioenergy is the amount of fossil fuel energy used to produce it.

Renewable Energy Certificates (RECs) – Tradable environmental commodities representing proof that a unit of electricity was generated from a renewable energy resource; RECs are sold separately from the electricity itself and thus allow the purchase of green power by a user of conventionally generated electricity.

Reuse – Method of returning materials to active use in the same or a related capacity and thus extends the lifetime of matrials that would otherwise be disposed. Examples of ongoing consumables that can be reused include binders, staplers, and other desk accessories, whether they are reused on-site or donated to other facilities.

Sedimentation – The addition of soil particles to waterbodies aby natural and human-related activities. Sedimentation often decreases water quality and can accelerate the aging process of lakes, rivers and streams (Eutrophication).

Setpoints – Normal ranges for building systems and indoor environmental quality; outside which action is taken.

Solar Reflectance – The ratio of the reflected solar energy to the incoming solar energy over wavelengths of approximately 0.3 to 2.5 micrometers. A reflectance of 100% means that all of the energy striking a reflecting surface is reflected back into the atmosphere; none of the energy is absorbed by the surface. The best standard technique for its determination uses spectro-photometric measurements with an integrating sphere to determine the reflectance at each different wavelength. An averaging process using a standard solar spectrum then determines the average reflectance (see ASTM Standard E903).

Solar Thermal Systems – Systems that collect or absorb sunlight via solar collectors to heat water that is then circulated to the building’s hot water tank. The hot water can be used to warm swimming pools or provide domestic hot water for residential and commercial use.

Source Energy – The total amount of raw fuel that is required to operate a building. It incorporates all transmission, delivery, and production losses, thereby enabling a complete assessment of energy efficiency in a building.

Source Reduction – Method of reducing the amount of unnecessary material brought into a building. Source Reduction = Not Purchasing the Item.

Stormwater Runoff – Water from precipitation that flows over surfaces into sewer systems or waterbodies. All precipitation that leaves project site boundaries on the surface is considered stormwater runoff.

Submetering – A method of determining the proportion of energy use within a building attributable to specific mechanical end uses or subsystems.

Sustainable Purchasing Policy – A policy that gives preference to products that have little to no negative impacts on the environment and society throughout its life cycle, and also gives preference to those products that are supplied by companies whom also have little to no negative environmental and social impacts. The sustainable purchasing policy commits the organization to an overarching course of action, which empowers staff working at the operations level.

Sustainable Purchasing Program – The development, adoption, and implementation of a procurement strategy, which culminates in the purchase of products that have little to no negative impacts on the environment and society through its life cycle of that are supplied by companies whom also have little to no negative environmental and social impacts. The program is an operational working strategy aligned and in support of an organization’s sustainable purchasing policy.

Telecommuting – Working by using telecommunications and computer technology from a location other than the usual or traditional place of business- for example, from home, a satellite office, or a telework center.

Thermal Comfort – A condition experienced by building occupants expressing satisfaction with the thermal environment.

Volatile Organic Compounds (VOCs) – Compounds that are volatile at typical room temperatures. The specific organic compounds addressed by the referenced Green Seal Standard (GS-11) are identified in EPA Reference Test Method 24, Code of Federal Regulations Title 40, Part 60, Appendix A.

Walk-off Mats – Mats placed inside building entrances to capture dirt, water, and other materials tracked inside by people and equipment.

Waste – All materials that flow from the building to final disposal. Examples include paper, grass trimmings, food scraps, and plastics. For this credit for LEED, waste refers to all materials that are capable of being diverted from the building’s waste stream of the building through waste reduction, including source reduction, recycling and composting.

Waste Diversion – A management activity that disposes of waste other than through incineration or landfilling. Examples are reuse and recycling.

Waste Reduction – Includes source reduction and waste diversion through reuse and recycling.

aste Reduction Program – (1) describes the organization’s commitment to minimizing waste disposal by using source reduction, reuse, and recycling, (2) assigns responsibility within the organization for implementation of the program, (3) lists the general actions that will be implemented to reduce waste, and (4) describes tracking and review procedures to monitor waste reduction and improve waste reduction performance.

Waste Stream – The overall flow of wastes from the building to the landfill, incinerator, recycling facility, or other disposal site.

Wind Energy – Electricity generated by wind turbines.