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innovation, and market demand. Based
on current developments, regulatory
frameworks are the most immediate
barrier. However, once a regulatory
framework is in place, technological
advancements and charterer demand
will accelerate adoption.
The IMO has initiated an overhaul
of the outdated Code of Safety for
Nuclear Merchant Ships (Resolution
A.491(XII)), with work assigned to the
Sub-Committee on Ship Design and
Construction (SDC) starting in January
2026. This revision aims to accommo-
date advanced reactor designs, such as
lead-cooled fast reactors, and concepts
beyond traditional pressurised water
reactors. Current efforts are focused on
addressing accident risks and liabilities
related to radioactive contamination.

What are the major technical challenges
in integrating nuclear power into
commercial vessels?
Traditional land-based nuclear reactors
are not suitable for commercial ships
due to their size, weight, and stability
requirements. Thus, developing com-
pact, lightweight reactors, like the
SMRs, that do not compromise cargo
capacity is essential. The designs must
also be marinised to withstand corro-
sion, vibration, and the inevitable ship
motions. At the same time, the reac-
tor’s output must align with the vessel’s
power needs, and operating reactors at
partial power to extend core life should
be avoided.
Since commercial hulls are less damage-
resistant than naval vessels, the risk
of a radiation leak during accidents
or extreme weather is increased. The
potential disruption of marine ecosys-
tems due to heat discharge from reac-
tors is another significant consideration.
Radioactive materials make ships tar-
gets for theft or attacks, mandating
robust security. Safety Protocols must
be created to minimise emergency
planning zones to the vessel’s footprint.
Shielding must prevent radiation expo-
sure to the crew and cargo during
operations and maintenance. Operat-
ing reactors requires highly specialised
personnel, which the maritime industry
currently lacks. Training programmes
for nuclear engineers and technicians

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