The ozone depletion factor of R-12 is ____.

The ozone depletion factor of R-12 is assigned a value of 1.0. This means that R-12 is considered to have a significant impact on ozone layer depletion, serving as a baseline for evaluating the ozone-depleting potential (ODP) of other substances. The ODP scale uses this value to compare other refrigerants; those with an ODP less than 1.0 have a smaller ozone-depleting effect relative to R-12, while those with a value greater than 1.0 would have a more substantial impact.

In this case, R-12, or dichlorodifluoromethane, is a chlorofluorocarbon (CFC), which was widely used in refrigeration and aerosol propellants but is now largely phased out due to its harmful environmental effects. Values less than 1.0 indicate substances that contribute less to ozone depletion compared to R-12, which is the reference point for this measurement.