HYDROCHLOROFLUOROCARBONS (Syllabus: GS Paper 3 – Env & Eco)

Context: In a promising environmental development, a new study has reported the first significant decrease in atmospheric concentrations of potent ozone-depleting substances (ODS) known as hydrochlorofluorocarbons (HCFCs).

Hydrochlorofluorocarbons (HCFCs)

• About: HCFC-141b is one of the most powerful ozone-depleting chemicals after Chlorofluorocarbons (CFCs).
• Usage: It is mainly used as a blowing agent in the foam manufacturing industries.
• Dependence on Imports: HCFC-141b is not produced domestically, and all requirements were met through imports.
• Non-Ozone Depleting Technologies: India is one of the few countries pioneering the use of non-Ozone Depleting technologies and has a low Global Warming Potential (GWP).
• Significant Phase-Out Achievement: The complete phase-out of HCFC-141b from the foam sector in India is among the first at this scale in Article 5 parties (developing countries) under the Montreal Protocol.

oDue to their ozone-depleting and greenhouse properties, HCFCs are being phased out globally under international agreements like the Montreal Protocol and its subsequent amendments.

• Montreal Protocol: The Montreal Protocol on substances that deplete the ozone layer is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion. It includes CFCs, HCFCs, HFCs etc. Signed in 1987, it came into effect in 1989.

Ozone Depletion

• About: Some compounds release chlorine or bromine when they are exposed to intense UV light in the stratosphere. 
• When chlorine and bromine atoms come into contact with ozone in the stratosphere, they destroy ozone molecules.
• Ozone-Depleting Substances: ODS that release chlorine include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), carbon tetrachloride, and methyl chloroform. 

oODS that release bromine include halons and methyl bromide.