Pre-consumer recycled content (synthetic gypsum) is created from environmental control systems installed in the smokestacks of coal-fired power plants. These systems capture particles from coal burning as they travel through the smokestack or flue. This becomes Flue-Gas Desulfurization (FGD) gypsum. FGD in drywall results in the global distribution of mercury, a potent developmental and neurotoxic metal that persists in the environment, accumulates in the food chain, and is highly toxic. The very pollution that is being captured in the flue of the power plant is being released from the smokestacks of wallboard factories that use FGD residuals. https://healthymaterialslab.org/tool-guides/hml-resources

Round metal ring which fits around the heat flue pipe after the pipe passes out of the roof.

The path down which water flows.

Large pipe through which fumes escape from a gas water heater, furnace, or fireplace. Normally these flue pipes are double walled, galvanized sheet metal pipe and sometimes referred to as a "B Vent". Fireplace flue pipes are normally triple walled. In addition, nothing combustible shall be within one inch from the flue pipe.

The land surrounding a flowing stream over which water spreads when a flood occurs.

An automatic door located in the flue that closes it off when the burner turns off; purpose is to reduce heat loss up the flue from the still-warm furnace or boiler.

2-foot lengths, fire clay or terra-cotta pipe (round or square) and usually made in all ordinary flue sizes. Used for the inner lining of chimneys with the brick or masonry work done around the outside. Flue linings in chimneys runs from one foot below the flue connection to the top of the chimney.

The ratio of the floor area of a building to the area of the lot.

A heavy coating of asphalt poured and spread over a surface.

A fluorescent lamp is a gas-filled glass tube with a phosphur coating on the inside. Gas inside the tube is ionized by electricity which causes the phosphur coating to glow. Normally with two pins that extend from each end.

End rafters of the gable overhang supported by roof sheathing and lookouts.

A by-product of coal burning at electricity plants. It is called "fly" ash because it is transported from the combustion chamber by exhaust gases. Fly ash can be substituted for portland cement in concrete or used as an additive in drywall. In these applications, it presents concerns because of its concentration of heavy metals such as mercury. https://healthymaterialslab.org/tool-guides/hml-resources

Large sections of formwork for pouring concrete slabs that are lifted from story to story by a crane in an assembled condition.

A mineral added to molten iron to cause impurities to separate into a layer of molten slag on top of the iron.

The unit of illumination equal to 1 lumen per square foot.

A unit for measuring brightness or luminance. It is equal to 1 lumen per square foot when brightness is measured from the surface.

Lower extremity of a foundation or loadbearing member that transmits load to load-bearing substrate.

Amount of applied energy to cause motion, deformation or displacement and stress in a body.

Continuous 8" or 10" thick concrete pad installed before and supports the foundation wall or mono-post.

The emission of visible light from a substance as a result of the absorption of radiation of short wavelengths.