Office for Nuclear Regulation

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Graded approach

A graded approach is a process which defines the level of analysis, the documentation and the actions necessary to comply with the safety requirements and criteria.

A graded approach helps:

Information on the application of the graded approach to the transport of radioactive material can be found on the ONR Transport web pages.

General requirements

Specific requirements can be found on the ONR application forms, and in the Ionising Radiations Regulations 2017 Approved Code of Practice and guidance L121.

Graded Approach Risk Applies to
Notify Low Work with 1,000kg or less of artificial or naturally occurring radionuclides that is one of the following:
  • between the low and medium end of specific concentration levels; and
  • above specific quantity levels.
Work in a radon atmosphere above an annual average of 300Bq m3.
Register Medium Radiation generators, such as X-ray devices, that are not a specific practice requiring consent.
Work with over 1000kg of artificial or naturally occurring radionuclides that is above the low end of specific concentration levels.
Work with over 1000kg of artificial or naturally occurring radionuclides that is above the medium end of specific concentration levels.
Consent Highest This will only apply to the following working practices:
  • deliberate administration of radioactive substances for specific medical or veterinary purposes;
  • uranium mining;
  • deliberate addition of radioactive substances into products;
  • operation of an accelerator (except an electron microscope);
  • industrial irradiation;
  • industrial radiography;
  • any practice involving a high-activity sealed source (other than one within industrial irradiation or industrial radiography);
  • long-term storage or disposal of radioactive waste; and
  • discharge of significant amounts of radioactive effluent.