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  • sustainability, environment

  • Related Articles
  • Montreal Protocol
  • WMO: World Meteorological Organization

  • Concept:

    Ozone depletion

    Depletion of Ozone layer, observed over the two poles is being relieved with the implementation of Montreal Protocol.

    This link was broken when checked on Dec. 2006How do refrigerants deplete the Ozone layer: "Refrigerant 22 (R-22 or MonoChloroDiFlouroMethane, CHClF2) is one of the most common refrigerants and is used in a wide variety of applications such as refrigeration, aerosol propellants, cleaning solvents, and foaming agents for plastics. This refrigerant is believed to be partially responsible for damaging the earth¡¯s ozone layer and it¡¯s use is being phased out over the next two decades. The ozone layer is a result of sunlight reacting with oxygen to produce a layer in the stratosphere more than 10 km above the earth¡¯s surface. As R-22 refrigerant escapes from an AC system through leaks or is released into the atmosphere by other means, the R-22 molecule containing the chlorine atom (¡°monochloro¡±) rises in the atmosphere. Sunlight breaks down the R-22 molecule to yield a free chlorine radical (Cl-). The free chlorine radical combines with ozone (O3), decomposing it into normal oxygen (O2).

    AC refrigerants come in many varieties. R-22 is the most common, however, due to interactions with the ozone layer R-22 is being phased out. Refrigerants manufactured as replacements for R-22 are HFC-134a, R-410a, R-410b to name a few. The new refrigerants do not contain the chlorine atom and are not harmful to the earth¡¯s ozone layer."

    Related References (3)
    Status of ratification/accession/acceptance/approval of the agreements on the protection of the stratospheric ozone layer, by UNEP, 2002
    Montreal Protocol status
    Successes and ongoing challenges - the international policy response to ozone depletion and its implications for health, by Shevlin, J., 1996
    Montreal Protocol
    The Montreal Protocol on Substances that Deplete the Ozone Layer as adjusted and/or amended in in London 1990, Copenhagen 1992, Vienna 1995, Montreal 1997, Beijing 1999, by UNEP, 2000

    CRDBER, at CBS, BCEE, ENCS, Concordia,