Sellafield gives you five working days to finish its Strength and Values assessment, and warns against using AI

Sellafield's own application guidance describes a Strength and Values assessment, not a reasoning paper, but a prep site reports SHL numerical and verbal tests in its graduate process, including a 30-question verbal test in 20 minutes. Our reasoning test practises that SHL style. For craft and operator routes, our mechanical test refreshes the plant science that comes up in technical conversations.

We found no source saying Sellafield apprentices sit a numerical, verbal or mechanical test, so both practice tests are insurance rather than a mirror. Neither rehearses the Strength and Values assessment, the video interview or the face-to-face assessment centre, and Sellafield publishes no pass mark.

Sellafield says candidates have five working days to complete the Strength and Values assessment in full. That is generous, and it is easy to waste. Open the link on the day it arrives, read the instructions, and book yourself a quiet slot within the first two or three days. If something goes wrong, such as a crash or a broken link, you then have time to contact the recruitment team before the deadline.

A strengths and values assessment asks how you prefer to work and what matters to you, often through workplace scenarios or statements to rate. Sellafield frames it as a way to understand your strengths and values, so there is nothing to revise. Our situational judgement guide explains how scenario tools of this kind are usually built.

Sellafield states that using AI during its online assessment and interview means you are not showing the genuine version of yourself. Some employers now say this; Sellafield says it directly on its application guidance. In a business that handles decades of nuclear material, honesty and following rules are part of the job, so the warning fits.

In practice: answer on your own, do not paste scripted answers into the video interview, and treat practice tools as preparation before the day, not help during it.

Sellafield's work is decommissioning and cleaning up the country's oldest nuclear site. Whatever your pathway, from business administration to mechanical craft and nuclear operator, safety and doing things properly come first. Before the assessment, read Sellafield's published values and think of one honest example for each from school, sport, work or family life.

Those examples do double duty: they settle your thinking for the online assessment and give you material for the video interview and the one-to-one at the assessment centre.

A prep site reports that Sellafield's graduate process has used SHL numerical and verbal reasoning tests, with the verbal test at 30 questions in 20 minutes, and that some candidates were asked to sit a second test to confirm earlier scores. That page is undated and describes graduates. Sellafield's own guidance, and the apprenticeship adverts we found, mention only the Strength and Values assessment.

If you want insurance, our numerical reasoning test runs in a similar style. Craft and operator applicants can also refresh forces, pressure and simple circuits with our mechanical aptitude test, useful background for talking about plant work.

Sellafield says its assessment centre is face to face, in West Cumbria or Warrington depending on the pathway. Candidates describe a group activity, a personal task and a short one-to-one interview, and some say nothing technical was asked. A 2026 nuclear engineering degree apprenticeship advert placed in-person assessment centres in March 2026, so for a 2027 start expect a similar spring date.

Plan the journey: West Cumbria sites can take a long time to reach by public transport. Arriving calm matters more than any last-minute revision.

These come from anonymous reviews, university careers pages and prep guides. They often disagree, and Sellafield Ltd has not confirmed them. Read them as leads, not rules.

• JobTestPrep reports SHL numerical and verbal reasoning tests in Sellafield's graduate process, with a verbal test of 30 questions in 20 minutes.
• JobTestPrep also mentions that some candidates may sit a second aptitude test to confirm earlier scores.
• Candidates on Glassdoor describe the assessment centre as a group activity, a personal task and a short one-to-one interview, and say nothing technical was asked.
• A 2023 case study published by Sova Assessment says Sellafield ran 14 virtual assessment centres in one graduate cycle, before the current face-to-face format.