Ozone depletion potential (ODP) is a metric used to quantify the relative ability of a substance to degrade the ozone layer compared to a reference substance, usually chlorofluorocarbon-11 (CFC-11), which is assigned an ODP of 1. Substances with higher ODP values have a greater capacity to deplete the ozone layer, contributing to increased ultraviolet radiation reaching the Earth's surface and associated environmental and health risks.