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In the late 1800s and 1900s, refrigerators had been operating on refrigerants such as Ammonia, Methyl chloride, and sulfur dioxide for food preservation and other cooling purposes. The fundamental rationale behind the use of refrigerators is for the prevention of bacteria from developing on food kept for a long time. The refrigerator was first introduced by John Gorie, an American physician in 1844. His intent for building this machine was to help patients with yellow fever maintain a regular low temperature of the environment.
Later, James Harrison created a refrigerator used for refrigerating foods in the year 1857. Though previously, people employ snow and ice for the purpose of cooling. As time goes on, refrigerator developers start utilizing refrigerants like ammonia, methyl chloride, and sulfur. The reason for using ammonia as a refrigerant was because of its significance in efficiency for larger systems, immediate awareness when spill into the environment, and its fast-spreading when discharged.
But because of its toxicity and flammability at high concentration and health problems to skin, lungs, and eyes, it was considered not valuable as a refrigerant anymore. On the other hand, the use of methyl chloride came to an end after many documented cases of leakage from refrigerators in 1920, hence, people were instructed to keep their refrigerators outside the kitchen or in the backyard.
The toxic effects of the foremost refrigerants stimulated three cooperative American companies to generate a safer alternative to substitute the initial chemicals. The collaborative effort of these three companies (Frigidaire, General Motors, and Du pout) yields a tremendous result as they synthesized less hazardous gas called chlorofluorocarbon (commonly known as freon as its brand name) by General Motors company assisted by Thomas Midgley in 1928. This gas consists of chlorine, fluorine, and carbon and it is classified under straight-chain aliphatic hydrocarbon. Scientists nominated CFCs for it's inert, polarity, high boiling points, odorless, and non-flammability with the awareness of its potent effects on the ecosystems in future years.
Later on, substances like cleaning solvents, refrigerants, aerosol propellants, and foams took advantage of CFCs due to its suitability. Practically, everyone believed that these CFCs were not harmful and this increased the demand for the gas. Almost every individual utilized freon including companies, air conditioning units, public health, and commercial Centers inclined toward freon products as the best coolant in 1932. More than one million metric tons of CFCs were produced annually according to NOAA.
Recently, the demand for CFCs reduced dramatically as scientists realized that chlorine included in the component induced potent effects on the atmosphere when escaping into the ozone layer.
Rowland, a chemist of California university with his colleague Molina, after attending a conference in 1972, took it upon themselves to study the effects of CFCs in the atmosphere when James Lovelock emphasized the number of CFCs accumulated already in the atmosphere since its inception.
Rowland from his analysis in 1974, discerned that CFCs that are considered inert at the lower atmosphere can still disassociate by the radiation of the sun and attack the stratosphere when released into the atmosphere. He acknowledged that when CFCs are decomposed by UV radiation, chlorine atoms tend to react with the three molecules of oxygen of the ozone thus, evoking a chain-like reaction that can destroy many parts of the ozone layer in the atmosphere, enhancing ozone depletion.
Experts affirmed that CFCs can prevail in the atmosphere for so many years due to its stability, destroying the ozone layer. Atmospheric ozone is believed to be a protective layer in the atmosphere that prevents the radiating heat of the sun from reaching the earth's surface. Also, the ozone layer helps existences on earth by absorbing ultraviolet radiation from harming animals and humans on land even Oceans. So if the amount of CFCs accumulated in the atmosphere is not controlled, the ozone layer would be decreased and then ultraviolet radiation from the sun will evoke health problems like cancer and cataracts.
When this potent of CFCs was understood, the industry began to develop another form of Halocarbons such as Hydrochlorofluorocarbon (HCFCs) and Hydrofluorocarbon (HFCs) as a substitute. The motive for adding hydrogen is that hydrogen can affect a short lifetime at a lower atmosphere when reacting with hydroxyl (OH) in the stratospheric ozone, unlike CFCs that would persist in the atmosphere for so many decades. But nevertheless, since HCFCs still consist of chlorine, however, there is a possibility of ozone depletion to occur when HCFCs split into the atmosphere. Therefore, HFC was regarded as a satisfactory substitute for CFCs.
Because of this consequence, CFCs have been banned from many developed and some developing countries. However, in the case where there is no suitable alternative to replace CFCs like in Halon fire suppression systems employed in submarines and aircraft, metered dose inhalers used in assisting asthma patients and serious pulmonary disease, there's no need to eliminate CFCs in this applications.
Strictly adhering to the Montreal Protocol, which was inaugurated on 10 September 1987, application of CFCs and HCFCs should be phased out and substitute would be employed. However, the utilizing of halocarbon is to be totally eliminated by 2030 for developed countries and 2040 for developing countries.
In conclusion, CFCs have many effects on human health and our environment as a whole. Inhalation of CFCs induce a severe effect on the central nervous system and if the skin is exposed to this gas, frostbite would occur on the skin.
Therefore, it is advisable to dispose of properly, old materials that still contain CFCs like Air Conditioning units and humidifiers in order to prevent and eradicate the spread of CFCs into the atmosphere, so that ozone depletion can be controlled.
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•Chlorofluorocarbons and Hydrofluorocarbons •Chlorofluorocarbons and ozone depletion
•Effects of climate change in Minnesota
•The History of Freon
•How to reduce CFCs emissions
•Major Appliances, Major History - The Refrigerator & Freezer
• Montreal Protocol
• The Basics of Ammonia Refrigeration
•The Purpose of Refrigeration
•What Effects do Chlorofluorocarbons Have on Humans?