- Montreal protocol was signed on September 16
- It is an international treaty planned for protection of ozone layer
- Ozone layer can be depleted by products with chlorofluorocarbons
International Ozone Day is observed on September 16. Also known as World Ozone Day, this event is meant to remind people about the signing of Montreal Protocol on reducing substances that deplete the ozone layer. The ozone layer or ozone shield is a region of Earth’s stratosphere which absorbs most of the Sun’s harmful ultraviolet radiation. The stratosphere contains ozone in high concentration, as compared to other layers of the atmosphere. Signed on September 16, 1987, the Montreal Protocol was signed on substances that deplete the ozone layer. The day for International Ozone Day was chosen by United Nations General Assembly in its 49/114 resolution.