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.

Ionizing electromagnetic radiation of wavelengths less than 10 nm.

A condition in which the center of the visual field is diminished due to retina damage.

Mineral or chemical additives usually used in concrete to achieve workability and/or impart desired properties.

Method of transmitting information from the senses to the central nervous system.

Cells that make up fat or adipose tissue and specialize in storing energy or calories as lipids.

A major herbicide that is very susceptible to running off or leaching into ground and surface water sources.

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.

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

An element found in the earth's crust that has applications in various industrial processes, however runoff from factories, agricultural practices and natural deposits can lead to high concentrations in water.

Among the most widely used pesticides in the United States and among the most commonly detected pesticide in drinking water.

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.

A compound that increases the risk of developing cancer.

A highly irritating, greenish-yellow gaseous halogen, capable of combining with nearly all other elements, produced principally by electrolysis of sodium chloride and used widely to purify water, as a disinfectant and bleaching agent.

Metallic element that enters water sources through natural deposits, but contamination most commonly occurs through corrosion of copper or brass.

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

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

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

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.

Refers to foods or organisms whose genetic material has been altered using genetic engineering. Though many legitimate criticisms of GMO foods exist, including gene copyrighting and potential environmental risks, GMOs are not inherently harmful and in some cases may be environmentally or nutritiously beneficial.

A non-selective herbicide used in many pesticide formulations; exposure may result from its normal use due to spray drift, residues in food crops and from runoff into drinking water sources.

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

H₂O₂ vapor is an unstable compound used especially as an oxidizing and bleaching agent and as an antiseptic; shown to reduce incidence of nosocomial infections from a number of pathogens, including some of the most harmful and antibiotic-resistant strains, including Clostridium difficile, VRE, MRSA and K. pneumonia.

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.

Bacteria and microscopic algae and fungi, especially those living in a particular site or habitat.

Enters groundwater and surface water by dissolution of rocks and soils, from atmospheric fallout and biological decays and waste disposal.

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.

A lipid, any of a diverse group of organic compounds including fats, oils, hormones and certain components of membranes that are grouped together because they do not interact appreciably with water, combined chemically with oxygen.

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

A family of fluorine-containing chemicals with unique properties to make materials stain- and stick-resistant.

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

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

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.

Sodium is consumed as sodium chloride in common salt. It is a vital nutrient, but unhealthy in high amounts.

A chlorinated hydrocarbon used as a dry cleaning solvent, an additive in textile processing and metal degreasing that has been linked to cancer.

A poisonous substance produced by a living organism.

Also called nanoparticles, ultrafine particles are a subcategory of PM₂.₅ 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.

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.

Intensity is the measurement of power per unit area (W/m²) and in acoustics is the rate of energy flowing from a sound source. Acoustic intensity, or sound intensity, is equal to the product of the sound pressure level and the acoustic particle velocity. Intensity is not the perceived sound level, rather a measurement of the sound wave amplitude, and it follows the inverse square law.

Percentage of space in which the light level from direct sun alone exceeds a pre-defined threshold (such as 1000 lux) for some quantity of hours (such as 250) in a year.

Measurement of luminous intensity and the SI base unit of light.

Clothing insulation is the resistance to heat transfer provided by clothing measured in clo (1 clo = 0.155 m²K/W = 0.88°F ft²h/BTU).

Spectral distribution of electromagnetic radiation of a blackbody at a given temperature. For example, the color temperature during the daytime is approximately 15,000 K, while during sunset is approximately 1,850 K.

A unit of measurement for sound. The decibel is a logarithmic unit so an increase in 10 decibels equals an increase by a factor of 10.

The time averaged sound pressure level on the A-weighted scale, converted to decibels.

Unit of illuminance, equivalent to one lumen per square foot.

Amount of light passing through a given area in space. Measured in lux or foot-candles.