Halocarbons or halons are constituents of

Halocarbons or halons are constituents of Fire extinguishers.
Halocarbons are carbon compounds that contain fluorine, chlorine, bromine, and iodine. Halocarbons that contain chlorine (CFCs and HCFCs) and bromine (halons) cause ozone depletion.
Clean agents extinguish the fire by displacing oxygen (CO₂ or inert gases), removing heat from the combustion zone or inhibiting the chemical chain reaction. Halon 1301 and 1211 are being replaced with new halocarbon agents which have no ozone depletion properties and low atmospheric lifetimes but are less effective.