Safety Case

Where STEM graduates with a passion for solving complex technical problems can join a team who form the backbone of nuclear safety, enabling all Sellafield Ltd missions

Description:

Safety Cases help us develop safe solutions for our projects and maintain safe conditions on our facilities.  The Safety Case is not only a fundamental requirement of our licence to operate, but essential in our understanding of hazards and safety controls.  Safety Case professionals work on projects and facilities site-wide and through the full lifecycle from design, through operations, to decommissioning and demolition.  They are responsible for not only understanding and analysing the hazards and risks that could occur, but identifying how safety can be managed and ensuring robust controls are implemented in practice.  All roles require you to operate as part of a multi-disciplined team, solving problems within a challenging context.

Safety Case specialist areas:

Criticality

A criticality incident is defined as an uncontrolled neutron chain reaction and is accompanied by large releases of radiation. Criticality safety aims to prevent a criticality incident from occurring, and for Criticality Assessors at Sellafield, this involves a range of work across all Value Streams from the storage of spent nuclear fuel to the management of special nuclear materials. A variety of technical skills are involved, and the use of Monte-Carlo codes for modelling the reactivity of fissile systems is also a key tool for identifying critical limits for the handling of fissile material on the Sellafield site.

Dose and Shielding

The Dose & Shielding specialism works to provide advice and guidance for projects and facilities to ensure they can operate safely within legal limits on dose uptake and company targets. Support is also provided on an ad-hoc basis to help advise the significance and potential mitigations for off normal events. The Shielding Design Process is used to produce appropriate documents at each stage of a project, which may include dose uptake assessments, criticality contours, and classification of areas. Dose & Shielding is a technical discipline which often requires the use of hand calculations or computer codes to quantify dose rates and dose uptake.

Nuclear Fire

Fire has three main ways it can cause harm on a nuclear site: it’s immediate harm to people and buildings, the ability to jeopardise safety measures provided to ensure nuclear safety, and initiating other fault scenarios. Nuclear Fire Safety focuses on assessing the fire scenarios that could happen, predicting the consequences of the fires, and managing the hazard following the safety hierarchy – Eliminate, Reduce, Control, Mitigate. Nuclear Fire Assessments are done both quantitatively and qualitatively, and can involve calculating heat transfer, fuel loading, and time equivalence as well as modelling fire scenarios using CFAST.

Radiological

Radioactive material has inherently hazardous properties which can cause harm to exposed workers or members of the public through internal and external dose. Radiological Safety Assessors are responsible for providing, fit-for-purpose and proportionate radiological safety advice and assessment for the whole of the Sellafield site. A radiological safety assessment involves understanding how a process, or operation is intended to progress normally then considers faults that could potentially occur and lead to radiological harm to an individual. Radiological assessors calculate the magnitude of the radiological uptake and identify appropriate controls to ensure that the risks associated with the identified hazards are managed. This involves working with various disciplines and incorporates a range of technical skills including knowledge of human and equipment reliability and radiological specialist computer modelling.

Typical roles and responsibilities:

Graduates in Safety Cases typically start in their first placement in the role of a Nuclear Safety Assessor (focussing on understanding nuclear hazards and controls) in one of the four main specialist areas – Radiological, Criticality, Dose and Shielding or Nuclear Fire. As part of their development, they are able to explore these different specialisms of nuclear safety assessment, as well as the opportunity to try a placement as a Safety Case Advisor (ensuring that nuclear safety controls are in place and maintained on a facility). Both roles offer a future career pathway, with foundational training that builds understanding of principles, and the opportunity to develop specialist skills. Graduates will get the opportunity for secondments in each of these roles or potentially wider within the company to other discipline areas with whom we work closely when developing safety cases (for example Operations, Design Engineering, Health Physics). Graduates in Safety Cases can expect to work on a range of facilities or projects during their training, at various stages of the facility lifecycle, getting hands-on experience throughout.

Progression possibilities:

Beyond the graduate training, Safety Cases career pathways offer a range of progression opportunities, whether through specialisation in a technical discipline or taking responsibility for the management of teams and safety cases for our nuclear facilities or major projects. The foundational training and broad experience gained on our programmes also offers a great platform for wider career options in technical, operational or leadership roles.

Location:

Sellafield, West Cumbria / Risley, Warrington. 

Suitable degree disciplines:

Our existing team has a wide range of STEM degree backgrounds. In particular, historically we have found the following degree areas are a good fit to the different safety case specialisms:

Criticality: Physics, Maths, Chemistry

Dose & Shielding : Physics, Maths, Chemistry

Fire: Engineering, Chemistry, Physics, Environmental Sciences

Rad: Any STEM degree

If you’re interested in joining our Safety Case Graduate programme, apply through the Safety job opening.