Mechanical Equipment Engineer

ALTEN is a global engineering and technology consultancy operating across over 35 countries worldwide. We partner with industry leaders across sectors including Aeronautics, Aerospace, Defence, Naval, Automotive, Energy, Rail, IT and many more to deliver innovative engineering solutions that drive technological advancement & support sustainable transformation.

Our teams of passionate and agile engineers work on cutting-edge projects that shape the future of technology and sustainability. At ALTEN, we empower talented engineers to innovate, solve complex challenges, and deliver impactful solutions that build tomorrow’s world—today.

Join us and start building tomorrow’s world today!

We are seeking a Senior Mechanical Equipment Engineer to support a major nuclear programme based in Oxfordshire. This is a long‑term contract opportunity working within an active nuclear environment, supporting detailed design, works testing, and equipment delivery.

• Deliver detailed design and specification of mechanical equipment including pumps, valves, and HVAC systems
• Produce and review equipment specifications, datasheets, and technical documentation
• Support works testing, installation, and commissioning activities
• Liaise with internal teams, vendors, and stakeholders to ensure equipment meets operational and safety requirements
• Support post‑operational activities including equipment associated with cleanout and grit‑blasting processes
• Ensure compliance with nuclear safety standards and project requirements

• Experience working as a Mechanical Equipment Engineer in a Senior or Principal capacity
• Strong detailed design experience within complex engineering environments
• Experience specifying and supporting mechanical equipment such as pumps, valves, and HVAC systems
• Experience supporting works testing and equipment verification
• Ability to work within highly regulated or safety‑critical environments

• A Bachelor’s or Master’s degree in Engineering, or equivalent military experience.

• Nuclear industry experience, particularly within active or operational facilities
• Experience supporting decommissioning, maintenance, or post‑operational cleanout activities
• Familiarity with nuclear site procedures and safety requirements

We bring together entrepreneurial, tech‑driven people to deliver innovative solutions for leading companies.

At ALTEN, you’ll work on exciting projects, supported by ongoing learning, mentoring, and clear career development tailored to your goals.

Join a passionate team and help build tomorrow, today.

• A personalised career path and a rewarding management style
• A huge diversity of engineering projects and industries
• Private Medical Insurance
• Cycle & Tech Scheme
• Employee assistance programme
• Life insurance & Pension Scheme
• Social atmosphere, regular gatherings & team buildings
• Flexible way of working (role dependent)

We are proud to support the Armed Forces Covenant & actively encourage applications from members of the Armed Forces community, including veterans, reservists, service leavers, and military spouses/partners. We recognise the value of military skills and experience and are committed to ensuring that no applicant is unfairly disadvantaged during our recruitment and selection processes.

This role may require you to have or be willing to go through Security Clearance. As part of the onboarding process candidates will be asked to complete a Baseline Personnel Security Standard; details of the evidence required to apply may be found on the government website  If you are unable to meet this and any associated criteria, then your employment may be delayed, or rejected .

Details of this will be discussed with you at interview.