GUIDANCE ON CALCULATING SOURCE CATEGORY FOR SEALED RADIOACTIVE SOURCES (link)
This guidance is to help you calculate the source categories of your sealed radioactive sources. It has been written for those who need to be authorised under the Environmental Authorisations (Scotland) Regulations 2018 (EASR) and for those who have a sealed source permit with a standard condition limiting source holdings by source category. This guidance does not cover calculations on security group of sealed sources.
Source: SEPA.