World Ozone Day, observed on September 16, raises awareness about protecting the ozone layer, which shields Earth by reducing harmful ultraviolet (UV) radiation reaching the surface. The day commemorates the Montreal Protocol, the international agreement adopted in 1987 to phase down ozone-depleting substances. The UN General Assembly (UNGA) established the day in 1994, and it was first observed in 1995. The Kigali Amendment to the Montreal Protocol promotes sustainable cooling and helps cut the climate impact of refrigerants.