There are various ways in which a licensed nuclear site, or part of a site may be removed from the licensing requirements of the Nuclear Installations Act 1965. Licensees can apply to ONR to delicense all or part of a site and effectively end their 'period of responsibility'.
ONR will consider applications for delicensing and will assess, from the licensees evidence and through information from other regulatory bodies (Environment Agency or Scottish Environmental Protection Agency), to ensure that no danger exists on site. The no danger criterion set by the Nuclear Installations Act must be met before ONR can make a decision on delicensing part or all of a site. Once satisfied, ONR will provide notice in writing to the licensee that there has ceased to be any danger from ioninsing radiations from anything on the site.