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
Occupational Safety and Health Administration (OSHA)
Occupational Safety and Health Administration, a branch of the U.S. Department of Labor responsible for establishing and enforcing safety and health standards in the workplace.
Occupied Zone
The volume of a conditioned space containing the occupants of the space, typically considered extending from floor level up to a height of 6 feet (1.8m).
Ocean Energy
Waves, tides, differential heat layers, and other sources of energy directly related to the world's oceans.
Odor Threshold
The minimum odor of a water or air sample that can just be detected after successive dilutions with odorless water. Also referred to as "threshold odor."
Off-Gassing
The emission of volatile organic compounds from synthetic and natural products. These fumes are unpleasant to breathe and may be hazardous to occupant health. Many new paints, carpeting, sealants, adhesives, and other building materials will do this for a time after installation.
Open-loop Process
Any process that does not fit the definition of "closed-loop process."
Open-loop Recycling
A recycling system in which a product made from one type of material is recycled into a different type of product (e.g., used newspapers into toilet paper). The product receiving recycled material itself may or may not be recycled.
Optimum Value Engineering (OVE)
Sometimes referred to as Advanced Framing. OVE Framing techniques use less lumber and therefore improve a structure’s level of insulation. Techniques include 24-inch on-center stud layout, single top plates, engineered header sizes, and special corner and wall configurations.
Organic Compound
Vast array of substances typically characterized as principally carbon and hydrogen, but that may also contain oxygen, nitrogen and a variety of other elements as structural building blocks.
Organic Farming
Avoiding the use of synthetic chemicals as fertilizers, pesticides, and herbicides when farming.
OSHA
Occupational Safety and Health Administration
Overshoot
The growth beyond an area's carrying capacity, which leads to a "crash."
Ozone (O3)
A naturally occurring, highly reactive, irritating gas comprising triatomic oxygen formed by recombination of oxygen in the presence of ultraviolet radiation. This gas builds up in the lower atmosphere as smog pollution, while in the upper atmosphere it forms a protective layer that shields the earth and its inhabitants from excessive exposure to damaging ultraviolet radiation.
Ozone Depletion
Destruction of the earth's ozone layer, which can be caused by the photolytic breakdown of certain chlorine- and/or bromine-containing compounds (e.g., chlorofluorocarbons),which catalytically decompose ozone molecules.
Ozone Hole
A thinning break in the ozone layer. Designation of amount of such depletion as an "ozone hole" is made when the detected amount of depletion exceeds 50 percent. Seasonal ozone holes have been observed over the Antarctic and arctic regions, part of Canada, and the extreme northeastern United States.
Ozone Layer
The protective layer in the atmosphere, about 12-15 miles above sea level, that contains a relatively high concentration of ozone which absorbs potentially harmful solar ultraviolet radiation in a wavelength range that is not filtered our by other atmospheric components.
