Office for Nuclear Regulation

Pregnant workers at Sellafield

Date released
19 August 2021
Request number


Release of information under
Environmental Information Regulations 2004

Information requested

Can the ONR forward the written justification document that covers this practice, under THE JUSTIFICATION OF PRACTICES INVOLVING IONISING RADIATION REGULATIONS 2004 for allowing pregnant women to work in buildings that would be affected in the event of a criticality at Sellafield, thereby exposing a human foetus to a potentially lethal dose of radiation.

Information released

I confirm that ONR does not hold information of the description specified in your request.

The Department for Business, Energy and Industrial Strategy (BEIS) has produced the guidance on application and administration of the Justification of Practices Involving Ionising Radiation Regulations 2004. Paragraphs 1.20-1.28 provide guidance on what constitutes a practice. A “practice” is “a human activity that can increase the exposure of individuals to radiation from a radiation source and is managed as a planned exposure situation” and the guidance expands on this further. A practice could for example be nuclear power generation and supporting activities.

Pregnant women working in controlled areas/areas that could be affected by ionising radiation or a criticality, is not a practice and therefore is not something that requires individual justification under these Regulations.

However, work with ionising radiation, including by pregnant women, is subject to controls under other regulatory provisions such as the Ionising Radiations Regulations 2017 (IRR17), in particular Regulation 8 requiring a radiation risk assessment and Regulation 9(6) requiring that the equivalent dose to the foetus is as low as is reasonably practicable and is unlikely to exceed 1 mSv during the remainder of the pregnancy.

The general requirements for risk assessment are contained within Regulation 3 of the Management of Health and Safety at Work Regulations 1999; Regulation 16 specifically requires assessment of risks in respect of new or expectant mothers. These requirements form part of a dutyholder’s management arrangements and systems, and ONR regularly considers those management arrangements and systems to ensure they are robust and compliant with legal requirements.

Further information can also be found in the Health and Safety Executive’s (HSE) L121 publication which sets out the IRR17 regulations, Approved Code of Practice (ACOP) and guidance. You may also find the HSE leaflets Working safely with ionising radiation: Guidelines for expectant or breastfeeding mothers and New and expectant mothers who work: a brief guide to your health and safety helpful.

Exemptions applied


PIT (Public Interest Test) if applicable