The release of chemicals from various substances under normal conditions of temperature and pressure. Offgassing can take a variety of forms, and is an issue of concern for some people, since some of the chemicals released during the offgassing process are potentially harmful.

Ozone (O3)

An unstable (reactive), and water soluble gas having chlorine-like odour, and formed in the upper atmosphere by the action of solar radiation on oxygen. Its presence as a layer in stratosphere serves as a screen (called the ‘ozone layer’) to block harmful ultraviolet radiation from reaching the earth's surface. At ground level it is formed by the combination of hydrocarbons and nitrogen oxides in the presence of sunlight and is the main ingredient of smog.

Ozone depletion potential (ODP)

The relative amount of degradation a chemical compound can cause to the ozone layer.