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General Terms

Acute Exposure

Single exposure to an environmental condition (not lasting more than a day). Acute exposures contrast with chronic exposures, which are prolonged and repeated. Single exposures still have effects on health.

Allergic Reaction

An exaggerated or pathological reaction (sneezing, respiratory irritation, itching or skin rashes) to substances that are without comparable effect on the average individual.


Small thin-walled air-containing compartments of the lung that are typically arranged in saclike clusters that give the tissue a honeycomb appearance and expand its surface area for the purpose of air exchange.

Alzheimer’s Disease

A type of dementia marked by the loss of cognitive ability, affecting memory, thinking and behavior generally over a period of 10 to 15 years.


Chronic inflammatory disease of the airways. Asthma attacks are often triggered by exposure to allergens, and during an attack the airways spasm, alternatively swelling and narrowing, causing the individual to wheeze or gasp for air.

Building Envelope

The separation between the interior and the exterior environments of a building, restricting transfer of air, water, heat, light, noise and creatures.

Chronic Diseases

Any disease that is persistent or has long-lasting health effects.

Chronic Exposure

Repeated, continuous exposure to a substance or condition over an extended period from several years to a lifetime.

Circadian Rhythms

Internal clock that keeps the body's hormones and bodily processes on a roughly 24-hour cycle, even in continuous darkness.

Cone Cells

Photosensitive cells in the eye used to differentiate colors and brightness in moderate and high levels of illumination.


A group of diseases that impact the metabolism due to insufficient insulin production (Type 1) and/or high insulin resistance (Type 2), and a leading cause of death. Results in poor blood sugar control, frequent urination, increased thirst, increased hunger and other symptoms.


Any of a group of unicellular, multicellular or syncytial spore-producing organisms feeding on organic materials.

Health Product Declaration (HPD)

A standard format for reporting product content and associated health information for building products and materials.

Heart Disease

A class of disease that affects the heart, arteries, capillaries or veins.

High Efficiency Particulate Air (HEPA) Filter

Filter which removes 99.97% of all particles greater than 0.3 micrometers and satisfies standards of efficiency set by the Institute of Environmental Sciences and Technology.


A state of having regulated responses to environmental conditions to retain stability.

Immune System

The integrated body system of organs, tissues, cells and cell products such as antibodies that differentiates self from non-self and neutralizes potentially harmful organisms or substances.


An inability to develop a normal immune response, usually as a result of disease, malnutrition or medical therapy that affects the immune system.


Localized protective reaction of tissue to irritation, injury or infection, characterized by pain, redness, swelling and sometimes loss of function.

Intrinsically Photoreceptive Retinal Ganglion Cells (ipRGCs)

Relay environmental light levels to the suprachiasmatic nucleus through the retinohypothalamic tract. Most sensitive to blue light.


An organ that plays a vital role in a range of important metabolic processes including detoxification, protein synthesis and glycogen storage.


A condition that results from insufficient nutrient intake, excess nutrient intake or nutrient intake in the wrong proportions.


Any biochemical process that occurs within an organism that is necessary to sustain life.

Metabolic Syndrome

A cluster of medical conditions or risk factors that increase the chances of developing cardiovascular disease, diabetes fatty liver disease and several cancers.


Different spectral distributions of light which produce the same response on the cones and are therefore visually identical.


Particles between 1 and 100 nanometers in size.

Neurocognitive Diseases

Diseases of the brain and nervous system.


A medical condition in which the accumulation of excess adipose tissue poses an adverse effect on health.


An infectious biological agent such as bacteria, virus and fungus that is capable of causing disease in its host.

Public Health Goals (PHGs)

Unenforced regulations developed by California Office of Environmental Health Hazard Assessment. Similar in concept to the EPA's Maximum Contaminant Level Goal (MCLG).


The energy and particles which are released during the decomposition process of atomic nuclei is called radiation.

Respiratory Failure

Inadequate gas exchange by the respiratory system, with the result that oxygen and/or carbon dioxide levels leaving the heart cannot be maintained within their normal ranges.


Light-sensitive membrane found at the back end of the eyeball that receives the image produced by the lens.

Rod Cells

Photosensitive cells in the eye used to discern peripheral vision in low levels of illumination.

Sick Building Syndrome (SBS)

A set of symptoms, such as headache, fatigue, eye irritation and breathing difficulties, that typically affect workers in modern airtight office buildings, and that are believed to be caused by indoor pollutants and poor environmental control.


A group of cells that perform a common and specified function. At an organizational level, tissues are between cells and organs.


Extent to which a substance is harmful to a living thing.

Ultraviolet Germicidal Irradiation (UVGI)

A sterilization method that uses ultraviolet (UV) light to break down microorganisms by destroying their DNA. Often used in a variety of applications, such as food, air and water purification.

Universal Design (UD)

Designing objects and spaces with aesthetically pleasing while maximizing accessibility, usability and operability regardless of the user's age, ability and other factors.


Physical stimuli which have an impact on the body's circadian rhythm. Examples include light, temperature and eating or drinking behaviors.

Free Address

Ability for occupants to be able to choose their own workspace within the office or workplace.

High-touch Surfaces

Surfaces that are frequently touched by building users and occupants such as door knobs, hand rails and tables. See Table A1.

Regularly Occupied Space

An areas where workers or other building occupants perform focused activities inside a building for an average of one hour a day or more.

Nap Pod

A personal dedicated resting space optimized to offer a short but regenerative sleep.


Any outdoor pathways designated for pedestrian or biker use.

Weather Resistant Barrier (WRB)

A sheet, spray- or trowel-applied membrane or material layer that prevents the passage of liquid water even after long or continuous exposure to moisture.

Sleep Hygiene

Personal habits and practices that help maximize sleep quality.

Ventilation Rate

Rate of exchange of outside air, as well as the circulation of air within the building.

National Ventilation Procedure

ANSI/ASHRAE Standards 62.1 is the recognized standard for ventilation system design and acceptable procedure with regards to establishing an effective ventilation system.

Heating, Ventilating, and Air Conditioning System (HVAC)

Equipment, distribution systems and terminals that provide the processes of heating, ventilating or air conditioning.

Occupational Safety and Health Administration (OSHA)

Outlines current indoor air quality guidelines for the workplace.

Photocatalytic oxidation (PCO)

Achieved when you combine UV light rays with a TiO2-coated filter.


Glasswork, which must be carefully designed in order to avoid excessive glare and heat gain.


Act of spatial problem solving.

Collaboration Zone

A physical area within a building that encourages group interplay and discussion though its strategic layout and design.

Focus Zone

A physical area within a building that encourages concentration and attentiveness to a task among occupants though its strategic layout and design.

Environmental Product Declaration (EPD)

Quantified environmental data for a product with pre-set categories of parameters based on the International Organization of Standards (ISO) 14040 series of standards, but not excluding additional environmental information.


An opening in a surface (as a wall or membrane).



Substances consisting of very fine particles of a liquid or solid suspended in a gas. For example, mist which consists of very fine droplets of water in air.


Environmental substance that can produce an allergic reaction in the body but may not be intrinsically harmful. Common allergens include pollen, animal dander, house dust, feathers and various foods.


Proteins generally found in the blood that detect and rid the body of potentially damaging organisms, such as bacteria and viruses.


A naturally occurring mineral that was commonly used in insulation because of its chemical and flame resistance, tensile strength and sound absorption properties. It is now known to be a leading cause of mesothelioma and lung cancer.

Carbon Monoxide

Colorless, odorless and highly poisonous gas formed by incomplete combustion. Replaces oxygen in hemoglobin, limiting blood's ability to deliver oxygen and can lead to death.


A compound that increases the risk of developing cancer.

Coarse Particles

Particulate matter larger than 2.5 micrometers and smaller than 10 micrometers in diameter; also called PM₁₀. Often found near roadways and dusty industries.


A hormone that playes a primary role in stress, during which it increases blood sugar, supresses the immune system and aids in protein, fat and carbohydrate metabolism. Also undergoes diurnal variation, playing an important role in the sleep-wake cycle.

Fine Particles

Particulate matter 2.5 micrometers in diameter or smaller. Can be directly emitted from combustion sources such as forest fires or can form when gases emitted from power plants, industries and automobiles react in the air. Also called PM₂.₅

Flame Retardants

Chemicals used in thermoplastics, thermosets, textiles and coatings that inhibit or resist the spread of fire. Some of these chemicals have been linked to cancer, delayed development, low IQ and thyroid disruption.

Food Additives

Substances typically added to processed foods to enhance or preserve flavor or appearance.


A colorless gas compound, HCHO. Used for manufacturing melamine and phenolic resins, fertilizers, dyes and embalming fluids as preservatives and disinfectants.


A simple sugar that is found naturally in small amounts in fruits and vegetables, but which occurs in extremely large quantities in many modern foods. High fructose intake has been implicated in liver disease, inflammation, metabolic syndrome, diabetes, heart disease and cancer.


Chemicals applied to crops or structures to reduce the harmful effects of mold, mushrooms and other fungi.


A group of pesticides commonly used on farms and lawns to eliminate weeds from the fields.


A chemical released by a cell, gland or organ that transmits a signal to another part of the body.


Made by forcing hydrogen gas into oil at high pressure in order to increase the shelf life and prevent rancidity of an oil.

Inorganic Chemicals

Refers to a chemical compound that is not "organic". Broadly, compounds not containing carbon.


A naturally occurring metal found deep within the ground. Used in creation of old pipes, ceramics and paint. Also the stable final element of uranium's radioactive decay series.


"Darkness hormone" whose levels inthe body is regulated by the circadian rhythm and the presence of light and in humans acts a driver for sleep.


A naturally-occurring poisonous metal element which occurs naturally in the earth's surface.


A chemical that is required for metabolic processes, which must be taken from food or another external source. Macronutrients taken from food sources include carbohydrates, proteins, fats and vitamins.

Organic Chemicals

Broadly refers to chemical compounds that possess carbon-based atoms, generally found in biological systems.


Triatomic form of oxygen. Hazardous to the respiratory system at ground level, but a layer in the upper atmosphere blocks much of the ultraviolet radiation from the sun.

Partially Hydrogenated Oil

Vegetable oils that have been hydrogenated or partially hydrogenated for the purpose of being solid at room-temperature, which contain trans-fats.


A synthetic resin used chiefly in paints and varnishes. Diisocyanates in poloyurethane products can be toxic if inhaled or touched during installation.

Polyvinyl Chloride (PVC)

An inexpensive plastic that is widely used for many objects. Exposure to its chemical precursors, additives and products of combustion can be harmful.


Radioactive, carcinogenic noble gas generated from the decay of natural deposits of uranium.


Neurotransmitter hormone produced in the gut and brain stem which regulates mood, sleep and digestion.


A poisonous substance produced by a living organism.

Ultrafine Particles

Also called nanoparticles, ultrafine particles are a subcategory of P₂.₅ which are exclusively less than 0.1 µm. Due to the small size they are often airborne and can easily reach the alveoli of the lungs.

Urea-formaldehyde (UF)

A low-cost thermosetting resin that is used in the wood product industry.

Volatile Organic Compounds (VOCs)

Organic, and therefore carbon and hydrogen containing, materials which evaporate and diffuse easily at ambient temperature. VOCs are emitted by a wide array of building materials, paints and common consumer products.


Any toxic substance, generally created by human activity.


A simple sugar that occurs widely in most plant and animal tissue. It is the principal circulating sugar in the blood and the major energy source of the body. Once eaten, carbohydrates break down immediately into glucose. Elevated blood glucose levels are one of the distinguishing elements of diabetes.


Any of a group of organic compounds that includes sugars, starches, celluloses and gums and serves as a major energy source to support bodily functions and physical activity. Easily digestible carbohydrates found in white bread, pastries and soda may contribute to weight gain and promote diabetes and heart disease.

Saturated Fat

Typically solid at room temperature, saturated fats are found in high concentrations in salmon, butter, bacon, beef and cheese.

Polyunsaturated Fat

Polyunsaturated fats are among the “good” fats that can help reduce cholesterol levels and risk of heart disease and stroke. Polyunsaturated fats are found in sunflower, corn, soybean and flaxseed oils, walnuts and many fish.

Decorative Glazing

Coating on window surfaces purely for aesthetic purposes with no other functionality.

Particulate Matter

A complex mixture of elemental and organic carbon, salts, mineral and metal dust, ammonia and water that coagulate together into tiny solids and globules.

Nitrogen Dioxide (NO₂)

A product of combustion mainly found near burning sources (for instance, wood smoke and traffic combustion).

Polychlorinated Biphenyls (PCBs)

A former commercially produced synthetic organic chemical compound that may be present in products and materials produced before the 1979 PCB ban.