CFCs details

Sources, Effects and control of CFCs

1. WELCOME TO THE PRESENTATION MAHDI HASAN ID-ER17050

2. Sources,Effects and Control of CFCs(Chlorofluorocarbons )

3. Chlorofluorocarbon is an organic compound that does not occur naturally. They are man-made gas.It contains carbon, chlorine, and fluorine, produced as a volatile derivative of methane ethane , and propane . CFC is also one of those gases involved in the greenhouse effect. It is particularly harmful because of its destructive reactions with ozone particles, which protects the earth from UV radiations . What is CFCs(Chlorofluorocarbons)?

4. Refrigerators and Air Conditioners Aircraft Halon Aerosol Sprays Foams Others Sources of CFCs(Chlorofluorocarbons)?

5. Ozone depletion Man-made compounds such as chlorofluorocarbons (CFCs), hydrofluorocarbons (HCFCs) and halons destroy ozone in the upper atmosphere (stratosphere). The stratospheric ozone layer makes life possible by shielding the earth from harmful ultraviolet (UV-B) rays generated from the sun. Decreased concentration of stratospheric ozone allows increased amounts of UV-B to reach the earth's surface . Effects of Chlorofluorocarbons (CFCs )

6. Figure:Mechanism of Ozone Layer Destruction by CFC in Stratosphere

7. While acting to destroy ozone, CFCs and HCFCs also act to trap heat in the lower atmosphere ,causing the earth to warm and climate and weather to change. HFCs, which originally were developed to replace CFCs and HCFCs, also absorb and trap infrared radiation or heat in the lower atmosphere of the earth . HFCs, CFCs and HFCs contribute an estimated 11.5% to present-day effect of GHGs on climate and climate change. Climate change

8. Inhaling CFCs Inhalation of CFCs affects the central nervous system, according to the New Hampshire Department of Environmental Sciences. The result is intoxication similar to that produced by alcohol , including lightheadedness, headaches , tremors and convulsions Immune System Deficiency CFCs can generally impair the human immune system, and scientists have linked direct expose to problems with the central nervous system.These problems might include difficulty Breathing or injury to the heart, kidneys and liver . Skin Cancer and Eye Damage Effects Of Chlorofluorocarbons on Humans

9. Air-Conditioning At present, most domestic systems use HCFC-22 , and while some existing industrial or commercial systems still use CFCs, equipment is being progressively retrofitted with an increasing uptake of HCFCs and HFCs . Refrigeration HCFCs have proven to bean efficient and easily accepted alternative in a number of applications, having many of the same characteristics as CFCs but with a reduced effect on the ozone layer. HCFCs however are also ozone depleting – although to a much lesser extent than CFCs . CFCs Alternatives and Encouraging

10. Foam A range of alternatives have replaced CFCs used in these applications including methylene chloride, hydrocarbons and HCFCs. HCFCs, particularly HCFC-141b, are an acceptable interim alternative that has replaced CFC for rigid polyurethane foam manufacture. Aerosol Products In the 1980s the majority of aerosol products were converted from using CFCs to hydrocarbon propellants . Medical and technical specialty products using CFC-12, CFC-11, CFC-113 have converted to alternatives including aqueous sprays and HFCs,

11. Montreal protocol The Montreal Protocol on Substances that Deplete the Ozone Layer (the Montreal Protocol) is an international agreement made in 1987. It was designed to stop the production and import of ozone depleting substances and reduce their concentration in the atmosphere to help protect the earth's ozone layer . Montreal Protocol control measures 1.With the exception of a very small number of internationally agreed essential uses that are considered critical to human health and/or laboratory and analytical procedures. 2.Based on 1989 HCFC consumption with an extra allowance (ozone depletion potential weighted ) equal to 2.8% of 1989 CFC consumption. International convention for CFCs control

12. 3. Up to 0.5% of base level consumption can be used from 2020 until 2030 for servicing existing refrigeration and air conditioning equipment. 4. Up to 2.5% of base level consumption can be used until 2040 for servicing existing equipment, subject to review in 2025. 5.All reductions include an exemption for pre-shipment and quarantine uses. 6.Some countries with economies in transition have a slightly delayed start to the HFC phasedown, but catch up to other developed party commitments by 2029. 7. Some developing countries have a delayed start to the HFC phase-down, starting their freeze in 2028 instead of 2024 and finishing at 85% reduction by 2047

13. Conclusion: Climate change is not our first planetary pollution crisis. Almost 40 years ago, scientists discovered that chemicals called chlorofluorocarbons (CFCs) were destroying the fragile ozone layer that protects us from the sun’s dangerous ultraviolet radiation.If we had failed to protect the ozone layer, hundreds of millions of people around the world would be condemned to suffer dreadful diseases, including skin cancer, eye cataracts and immune system disorders. And we would be enduring devastating disruption of world food production , especially in the developing world.

14. 1.https ://www.environment.gov.au/protection/ozone/montrealprotocol#:~:text=The%20Montreal%20Protocol%20on%20Substances,protect%20the%20earth's %20ozone%20layer . 2.https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.environment.gov.au/s ystem /files/resources 3. https://www.pca.state.mn.us/air/chlorofluorocarbons-cfcs-and-hydrofluorocarbons-hcfcs 4.https://brainly.in › question Write the cause of depletion of ozone layer. How can we prevent ... 5.https://chem.libretexts.org › Kinetics Web results 7.3: Depletion of the Ozone Layer - Chemistry LibreTexts 6.https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.pca.state.mn.us/air/ch lorofluorocarbons -cfcs-and- hydrofluorocarbon 7. https://sciencing.com/sources-cfcs-8405334.html 8.https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.ciesin.org/docs/011- 459/011-459 References:

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