CFC11n

CFC11n, also known as trichlorofluoromethane, is a synthetic chemical compound belonging to the chlorofluorocarbon (CFC) family. It was historically used as a refrigerant, propellant in aerosol sprays, and a blowing agent for foam insulation. Its chemical formula is CCl3F. CFC11n is a colorless, odorless liquid at room temperature that is non-flammable and generally non-toxic. Its stability and inertness made it highly desirable for various industrial applications throughout the mid-20th century.

However, research in the late 20th century revealed that CFC11n is a potent ozone-depleting substance. When released into the atmosphere, it rises to the stratosphere where it is broken down by ultraviolet radiation. This process releases chlorine atoms, which then catalyze the destruction of ozone molecules. The depletion of the ozone layer allows more harmful ultraviolet radiation to reach the Earth's surface, increasing the risk of skin cancer, cataracts, and damage to ecosystems.

Due to its significant environmental impact, the production and use of CFC11n have been largely phased out globally under the Montreal Protocol on Substances that Deplete the Ozone Layer, an international treaty established in 1987. While its use has dramatically decreased, legacy emissions from existing equipment and potential illegal production remain areas of concern for atmospheric scientists monitoring ozone recovery.