Ozone Depletion by wpv17ts

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									Ozone Depletion
 Reducing the manufacture
      and release of
   halogenated organic
        chemicals
What are halogenated organic
chemicals?
    CFCs
        Chlorofluorocarbons
    HCFCs
        Hydrochlorofluorocarbons
CFCs
    Can (in some cases used to) be found in:
        Aerosol sprays
        Cleaning fluids
        Freezers
        Air conditioners
        Refrigerators
        Industrial solvents
        Dehumidifiers
        Foam insulation
HCFCs
    Are found in:
      Heat pumps
      Central air conditioners
A Brief History and Status
  1978 – US banned CFC’s as propellants in
   aerosol products
  1987 – “Montreal Protocol on Substances that
   deplete the Ozone Layer” International
   conference to control these chemicals.
   Signed by US and 22 other countries
        Limited production and use of CFC’s
        50% reduction in CFC production worldwide by
         2000
A Brief History and Status
    “Montreal Protocol on Substances that
     deplete the Ozone Layer”
      Now signed by over 90 nations
      Revised to require the virtual phaseout of
       CFC production by 1996
    1990 – US “Clean Air Act Amendment”
     passed
Alternatives and Replacements
    HCFCs (hydrochloroflurocarbon)
      Positive aspects – Break down more
       quickly in the atmosphere posing less
       danger to the ozone layer
      Negative aspects – if overused they could
       cause damage to the ozone layer in the
       same way as CFC’s. Redesigned
       appliances could use more energy than the
       original models
Alternatives and Replacements
    HFCs (Hydrofluorocarbons)
      Positive aspects – do not contain chlorine
       and are therefore safe for the ozone layer
      Negative aspects – safety questions such
       as flammability and toxicity still unclear
Alternatives and Replacements
    Hydrocarbons (such as butane and
     propane)
      Positive aspects - they are relatively cheap
       and readily available
      Negative aspects – can be flammable and
       poisonous and some increase ground-level
       pollution
Alternatives and Replacements
    Ammonia
      Positive aspects – A simple alternative for
       refrigerators
      Negative aspects – Must be handled
       carefully
Alternatives and Replacements
    Water (and Steam)
        Positive aspects – Effective for some
         cleaning applications
Other Options and
Alternatives
  Serious attempt at the control of the
   production, use, and emission of ozone-
   depleting chemicals world-wide
  Enforce by law and increase the
   recycling of these chemicals
  Enforce and regulate the servicing of
   refrigeration and air conditioning
   equipment
Other Options and
Alternatives
  Regulate and promote safe disposal
  Approve and enforce the use of alternative
   chemicals that do not harm the ozone
  Regulate and enforce that CFCs and HCFCs
   are handeled legally when servicing or
   disposal of air conditioners
  Proper protection against the UV radiation
   from the sun
Assignment
    3.2.5: Research 1 national and 1
     international agency/organization. Be
     prepared to describe, compare, and
     evaluate their roles in the reduction of
     emissions of ozone-depleting
     substances

								
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