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Chlorofluorocarbons (CFCs): when derived from methane and ethane these compounds have the formulae CCl m F 4−m and C 2 Cl m F 6−m, where m is nonzero. Hydro-chlorofluorocarbons (HCFCs): when derived from methane and ethane these compounds have the formula CCl m F n H 4−m−n and C 2 Cl x F y H 6−x−y, where m, n, x, and y are nonzero.
The ozone depletion potential (ODP) of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane (R-11 or CFC-11) being fixed at an ODP of 1.0. Chlorodifluoromethane (R-22), for example, has an ODP of 0.05. CFC 11, or R-11 has the maximum potential amongst chlorocarbons because of the ...
Another factor that may prolong ozone depletion is the drawdown of nitrogen oxides from above the stratosphere due to changing wind patterns. [122] A gradual trend toward "healing" was reported in 2016. [24] In 2019, the ozone hole was at its smallest in the previous thirty years, due to the warmer polar stratosphere weakening the polar vortex ...
CFCs are stable molecules composed of carbon, fluorine, and chlorine that were used prominently in products such as refrigerators. The threats associated with reduced ozone pushed the issue to the forefront of global climate issues and gained promotion through organizations such as the World Meteorological Organization and the United Nations .
Semi-empirical ozone depletion potential, ODP (normalized to be 1 for R-11) Net global warming potential , GWP, over a 100-year time horizon (normalized to be 1 for R-744 , carbon dioxide) Occupational exposure limit / permissible exposure limit in parts per million (volume per volume) over a time-weighted average (TWA) concentration for a ...
Equivalent effective stratospheric chlorine (EESC) provides an estimate of the total effective amount of halogens (chlorine and bromine) in the stratosphere.It is calculated from emission of chlorofluorocarbon and related halogenated compounds into the troposphere (lower atmosphere) and their efficiency in contributing to stratospheric ozone depletion (ozone depletion potential, ODP), and by ...
CFC-113 was one of the most heavily produced CFCs. In 1989, an estimated 250,000 tons were produced. [5] It has been used as a cleaning agent for electrical and electronic components. [12] CFC-113’s low flammability and low toxicity made it ideal for use as a cleaner for delicate electrical equipment, fabrics, and metals.
Trichlorofluoromethane, also called freon-11, CFC-11, or R-11, is a chlorofluorocarbon (CFC). It is a colorless, faintly ethereal, and sweetish-smelling liquid that boils around room temperature. [5] CFC-11 is a Class 1 ozone-depleting substance which damages Earth's protective stratospheric ozone layer. [6]