Senior or Principal Process Engineer

Assystem is an international company with one mission: accelerate the energy transition around the world.

Every day, our 7,500 switchers located in 12 countries (Europe, Middle East, Pacific Asia & Africa) connect their six thousand billion neurons to tackle the task of the century: switching to low-carbon energy.

We are a collective committed to the actors who are making the energy switch. Sharing our knowledge, expertise and values allows us to innovate and think differently about the energy transition.

Drawing on more than 55 years' experience in highly regulated sectors subject to strict security and safety requirements, we provide our customers with engineering and project management services, as well as digital services and solutions to optimize the performance of complex infrastructure projects throughout their life cycle. The Group is currently ranked third in the world for nuclear engineering.

To ensure a viable, efficient, and reliable energy future for all.

Your Mission on this Role: 

Principal Process Engineer 

Join Assystem's multi-disciplinary engineering team supporting one of our major clients. You'll work alongside Mechanical, Civil, Electrical, and Piping Engineers to ensure safe, compliant, and efficient design and operation of nuclear facilities.

Key Responsibilities

• Develop, author, and maintain Infrastructure Design Substantiation documents

• Manage design changes and concessions, ensuring compliance with safety and regulatory standards

• Prepare and present design justifications to client nuclear safety committees

• Produce and maintain EIMT (Examination, Inspection, Maintenance & Testing) schedules and reports

• Contribute to Periodic Review of Safety reports and assessments

• Provide technical advice and guidance to internal and external stakeholders

• Conduct Independent Technical Assessments (ITA) and Peer Reviews (IPR)

• Apply advanced engineering methods and technologies in a high-hazard nuclear environment

• Review and approve technical reports, calculations, and safety case submissions

Essential Skills & Experience

• Proven experience producing key Process Engineering deliverables – Basis of Design, Mass Balances, PFDs, P&IDs, Schedules, Datasheets, and Calculations

• Strong knowledge of British & European design standards and best practices

• Hands-on experience across concept, detailed design, and construction stages (industrial and/or maritime projects preferred)

• Skilled in design assessment of plant and equipment against potential hazards

• Ability to produce robust technical justifications and documentation for design modifications in high-hazard environments

• Experience working on multi-disciplinary engineering projects, providing key process input

Desirable Skills

• Previous experience in high-risk or nuclear environments

• Familiarity with safety case development techniques (e.g., HAZID/HAZOP)

• Experience in the UK nuclear industry (energy or defence) – design and assessment of safety-related systems and components

• Knowledge of UK & US nuclear regulations, codes, and standards

Qualifications & Training

• Essential:

  • Minimum HNC (or equivalent) in a relevant engineering discipline

  • Incorporated Engineer status or equivalent experience

  • Willingness to complete a Nuclear Introductory Course within 6 months (if from a non-nuclear background)

• Desirable:

  • Engineering Degree (BEng/MEng)

  • Chartered Engineer (CEng) status

Due to the nature of this role the successful candidate will require Security clearance. To gain this they will be required to be a Sole UK national,  Hybrid working from home/Assystem Office

Benefits include:

• Pension scheme (8% company contribution / 4% personal contribution)
• 25 days' paid annual leave + bank holidays + option to buy or sell days
• Professional fees reimbursed
• Flexible working
• Employee referral scheme

Sole UK National, SC clearance required to start 

Umbrella contractor or staff

Hybrid role with 2-3 days per week in the Client office in central Glasgow and occasional travel to the main Client site near Helensburgh

Umbrella contractor or staff position

We are committed to equal treatment of candidates and promote, as well as foster all forms of diversity within our company. We believe that bringing together people with different backgrounds and perspectives is essential for creating innovative and impactful solutions. Skills, talent, and our people's ability to dare are the only things that matter . Bring your unique contributions and help us shape the future.