Most nuclear engineering services are sold in phases. Design here. Commissioning there. Decommissioning handed to whoever’s available when the time comes. That’s a problem.
Nuclear programmes don’t work in phases. They work in decades. A decision made in year two carries consequences into year 40. The consultancy that helped with front-end engineering design may have long since moved on. The knowledge they built often goes with them.
The result tends to be cost overruns and compliance gaps, alongside documentation that no longer reflects what’s in the ground. Most of it is preventable. Rarely is it talked about openly.
Here’s what the full picture looks like, and why who you choose matters more than most clients realise.
End-to-End Nuclear Engineering Support Across the Programme Lifecycle
Nuclear programmes are long. Hinkley Point C is expected to operate for 60 years. The UK’s decommissioning estate won’t be fully cleared until well into the next century.
Between those points, there’s construction, commissioning, operations, through-life support and eventual decommissioning, each governed by distinct engineering demands, regulatory obligations, workforce requirements and oversight frameworks.
The table below sets out what each phase typically involves, where support most often fails and what good looks like.
| Programme phase | Typical duration | UK context | Where engineering support most often fails |
| Front-end engineering design (FEED) | 2 to 5 years | Sizewell C (pre-construction phase) | Design decisions made without through-life thinking |
| Construction and commissioning | 6 to 15 years | Hinkley Point C (construction from 2017; Unit 1 expected online 2030) | Interface failures between discipline teams |
| Operations and through-life support | 20 to 60 years | UK AGR fleet: average 40+ years operational | Knowledge loss at handover; ageing asset risk |
| Decommissioning | 10 to 100+ years | NDA estate: discounted provision of £110bn across 17 sites (NDA 2024/25) | Incomplete technical records; workforce gaps |
Each phase has a version of the same underlying problem. The wrong engineering support, at the wrong time, costs far more to fix than it would have cost to prevent.
Phase One: Front-end Engineering Design
This is where the safety case begins to take shape. It’s also where the most expensive mistakes are made.
FEED for a nuclear programme carries unusual weight. The design decisions made at this stage shape cost and compliance risk for decades. Choices about materials, layout, systems and interfaces all compound through every phase that follows. Reversing them is rarely an option.
Nuclear engineering services entering at FEED need to understand regulatory obligations from the outset. The Office for Nuclear Regulation (ONR) expects a safety-informed approach to design, not a retrofit applied once the drawings are half-finished but systems engineering integrated with the safety case from day one.
We supported EDF at Sizewell C during the pre-construction phase, delivering detailed topographic surveys and visual data across 275 hectares to inform planning and enabling works. Getting accurate spatial intelligence to the engineering team early changes what’s possible downstream.
Phase Two: Construction and Commissioning
A nuclear construction site is unlike any other. Interface management between structural, mechanical, electrical, HVAC and instrumentation and control teams is one of the highest-risk activities on any programme. When something slips through the gaps, it tends to do so quietly.
This is where embedded, multi-disciplinary nuclear engineering services earn their place. A team working across specialisms, with shared accountability for programme outcomes, is a different proposition from a roster of separate firms managing their own workstreams.
Commissioning adds another layer. Test protocols, certification submissions, handover documentation and as-built records for a nuclear facility carry regulatory consequences. Done poorly, they create liability that follows the programme for its entire operational life.
Our test and commissioning capability spans SMR design verification through to defence nuclear certification. Work that demands technical rigour alongside appropriate security clearance and close coordination with regulators.
Phase Three: Operations and Through-life Support
This is the longest phase and, in practice, the most neglected when clients are selecting nuclear engineering services at the outset.
A reactor that operates for 40 years will outgrow its original documentation. Modifications accumulate. Workarounds become standard practice. Informal knowledge builds up over time and never makes it into the asset register. When the engineers who built it retire, that knowledge doesn’t retire neatly. It leaves.
Reliability-centred maintenance (RCM) is one of the tools that addresses this systematically. Rather than waiting for failure or running on fixed-interval schedules, RCM matches maintenance effort to actual failure modes and operating context.
Morson Praxis applied this at Sellafield across nuclear asset management programmes covering multi-disciplinary design, plant modifications and day-to-day engineering support. They’ve received 14 consecutive RoSPA President’s Awards there. Through-life support isn’t a separate service. It should be designed in from the start.
Phase Four: Decommissioning
The Nuclear Decommissioning Authority (NDA) manages a legacy estate across 17 sites, with a discounted decommissioning provision of £110 billion (NDA Annual Report 2024/25). The scale and technical complexity are both formidable.
Decommissioning engineering requires something most nuclear engineering services rarely discuss openly. The ability to work with incomplete, ageing or partially lost technical records. When documentation from original construction no longer reflects what’s in the ground, you need engineers who can reconstruct what’s actually there and make it safe, not just follow a plan.
Morson Praxis has worked at Dounreay in northern Scotland, one of the UK’s most technically complex decommissioning sites. The work demands the same precision as new build, with far less certainty about what you’ll find. That combination tests everything a nuclear engineering team is made of.
The Advantage That Changes the Calculation
All four phases share a common thread. Each one requires continuity of knowledge and security-cleared teams, along with the capacity to scale when the programme demands it.
Nuclear programmes accelerate and decelerate. Regulatory milestones and funding decisions, combined with supply chain pressures, mean the engineering resource requirement is rarely flat. Most consultancies can’t move quickly when a programme needs to scale. Finding engineers with nuclear clearances and relevant skills at short notice takes an infrastructure they don’t have.
Morson Praxis is part of the Morson Group. That means direct access to Morson’s recruitment engine (Edge) and its workforce development arm (Nexus). When a programme needs to scale, they’re not calling an external agency. They’re drawing on the UK’s third-largest engineering staffing operation and a workforce development capability built for exactly this kind of demand.
It’s a combination that’s uncommon in the market. In nuclear, where programme continuity is everything, it changes the calculation.
Nuclear Engineering Services That Go the Distance
Nuclear engineering services that cover only part of the programme aren’t really lifecycle support. They’re project delivery with a nuclear badge.
Morson Praxis works across new build, through-life operations, SMR programmes and decommissioning – with systems engineering, RCM capability, digital engineering tools and security-cleared teams across all of them. If your programme spans decades, your engineering partner should too.
