General Science question from Laboratory Attendant exam, 2026 by JKSSB
Which of the following ozone-depleting substances are correctly matched with their primary sources?
Last updated Jun 18, 2026
Correct Answer:
Option D —
Chlorofluorocarbons (CFCs) Refrigerants and aerosol propellants
Here is why this match is correct and where the other ozone-depleting substances (ODS) actually come from:
The Correct Match
D) Chlorofluorocarbons (CFCs): Historically used extensively as cooling fluids in refrigerants (like air conditioners and refrigerators) and as propellants in aerosol spray cans. Because of their severe impact on the ozone layer, they have been heavily phased out globally under the Montreal Protocol.
Mismatched Pairs Corrected
A) Halons: Their primary source is fire extinguishers and explosion suppression systems, not soil fumigants.
B) Methyl bromide: This is a broad-spectrum pesticide used primarily as an agricultural soil fumigant to control pests, weeds, and diseases. It is not used as a degreasing solvent.
C) Hydrochlorofluorocarbons (HCFCs): Developed as temporary replacements for CFCs, their primary use is in refrigeration, air conditioning, and foam manufacturing, rather than fire extinguishers.
Answer verified by Quintessence Classes faculty — Karan Nagar, Srinagar.
