Possible Clues:

• Ozone depleter, briefly
• Phased-out propellant
• Banned aerosol propellant, for short
• Freon initials
• Ozone-depleting compound, for short
• Ozone-threatening compound
• Compound once used as aerosol propellant: Abbr
• Refrigerant inits
• Freon, generically
• Ozone hazard, for short