This International Standard provides criteria for emergency preparedness and response to minimize consequences due to a nuclear criticality accident. The criticality safety of operations are evaluated in accordance with ISO 1709.This International Standard applies to a site with one or more facilities which might contain signifcant quantities and concentrations of fssile material. The extent to which this International Standard needs to be applied depends on the overall criticality risk presented by the facilities at the site.This International Standard does not apply to off-site transport and transit storage of packages with fssile material.This International Standard does not apply to sites with operating nuclear power plants or to facilities with research reactors which are licensed to become critical or near-critical, provided that there are no operations with fssile material external to the reactor for which a credible criticality accident risk exists. This International Standard can be applied to such sites and facilities in specifc cases, if supported by site management and by licensing authorities.