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Ozone Depleting Substance

Ozone depleting substances are man-made gases that destroy ozone once the gases reach the ozone layer. The ozone layer sits in the upper atmosphere and reduces the amount of harmful ultra violet radiation that reaches Earth from the sun. 

Ultraviolet radiation can have detrimental effects on both humans and the environment such as inducing skin cancer and cataracts, distorting plant growth and damaging the marine environment.

Ozone depleting substances include:
  • chlorofluorocarbons (CFCs)
  • hydrochlorofluorocarbons (HCFCs)
  • hydrobromoflurocarbons (HBFCs)
  • halons
  • methyl bromide
  • carbon tetrachloride
  • methyl chloroform
They have been used as:
  • refrigerants in commercial, home and vehicle air conditioners and refrigerators
  • foam blowing agents
  • a component in electrical equipment
  • industrial solvents
  • solvents for cleaning (including dry cleaning)
  • aerosol spray propellants
  • fumigants. 
According to MARPOL annex 6, requirement for control of emission from ships
  1. Any deliberate emissions of ozone-depleting substances shall be prohibited. 
  2. Deliberate emissions include emissions occurring in the course of maintaining, servicing, repairing or disposing of systems or equipment, except that deliberate emissions do not include minimal releases associated with the recapture or recycling of an ozone-depleting substance. 
  3. New installations which contain ozone-depleting substances shall be prohibited on all ships, except that new installations containing hydrochlorofluorocarbons (HCFCs) are permitted until 1 January 2020.
  4.  If required to dispose off,shall be delivered to appropriate reception facilities when removed from ships.

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