In a fast-evolving maritime industry, safety must remain a priority, says Knut-Ørbeck Nilssen, CEO, DNV Maritime.
These are exciting and challenging times for the maritime industry.
Although decarbonization and digitalization are driving rapid transformations, geopolitical and economic shifts are introducing new uncertainties and leading to a range of side effects, most notably an increasingly ageing fleet.
Amid these changes, safety must never be compromised.
As shown in Lloyd’s List Intelligence data from this year’s safety report, a clear correlation has emerged between an ageing global fleet and an uptick in safety incidents over the past two years.
Elevated freight rates – largely driven by the re-routing of vessels and leading to a tonne-miles driven market – have led many shipowners to delay the scrapping of older vessels to maximize earning potential.
While these are logical commercial decisions, they are not without side effects. As the data shows, 52% of all casualties in 2024 came from vessels which were 20 years old or above, a significant increase compared to 10 years ago when this figure was 43%.
Ship technology continues to evolve at an impressive pace and newer vessels are increasingly equipped with advanced hull design, cutting-edge fire suppression systems, and sophisticated navigation systems, significantly enhancing safety. However, with older vessels often lacking these features it is not surprising that they account for a growing share of global maritime casualties.
Many vessels currently in service were designed for a different era, with different regulatory standards and technological capabilities. As these ships continue to operate beyond their intended lifespans, the risks associated with structural fatigue, outdated systems, and limited compatibility with modern safety technologies increase.
Economic considerations will always influence decision-making, but safety should never be compromised.
While retrofitting older vessels with the latest systems may be difficult, measures such as more frequent maintenance and timely replacement of ageing components can go a long way in mitigating risk.
At the same time, we must remain vigilant as we adopt new technologies. The maritime sector is seeing the emergence of alternative-fuel engines, larger and more complex vessels with energy-saving devices, hybridization, and increased automation. These innovations are essential to achieving our decarbonization goals, but they must be developed and deployed with safety at the core, with advanced safety systems and technologies integrated into vessel design from the very beginning.
This can result in improved situational awareness, reduced human error, and more resilient vessels.
Digitalization is another area of rapid progress, helping to maximize efficiencies and facilitating a more connected maritime value chain. However, this also brings new safety risks.
Great strides are being made in areas like autonomy and remote operation, with these holding the promise of optimized logistics chains, improved cargo capacity, and reduced costs. However, regulations are still evolving for these more advanced technologies, driving the need for frameworks that will ensure they are at least as safe as conventional vessels.
An increasingly interconnected maritime industry also naturally increases its vulnerability to cybersecurity threats. The impact of a cyberattack can be far-reaching, but there are still some gaps in awareness and preparation.
Cybersecurity, like all safety considerations, must be embedded from the earliest design stages through to day-to- day operations. This will help ensure that vessels are more resilient and robust and enable them to more easily fit in with modern, integrated networks.
One of the key aspects of enhanced safety is the protection of seafarer health and well-being. Every day, tens of thousands of men and women around the world set sail, facilitating the delivery of goods to every corner of the planet.
With so many novel technologies emerging, and safety threats constantly evolving, it is crucial that these vital men and women are equipped with all the tools they need to ensure safety, accompanied by fit-for-purpose training programs.
At the same time, we must not overlook the risks posed by an ageing fleet. Innovation is vital but so is managing older vessels responsibly. This means maintaining them to high standards and sending them off to recycling at the right time.
Finally, greater industry transparency and incident shaing are critical to improving safety culture. The smoke and
mirrors surrounding the dark and parallel fleets are a major safety concern, and regrettably these vessels sail in stealth mode under the radar of our safety monitoring.
The challenges ahead are complex, but they are not insurmountable. By working together – across sectors, borders, and disciplines – we can build a safer, smarter, and more sustainable maritime industry.
Ageing fleet driving increase in incidents
A clear uptick in casualties in 2024, driven by machinery damage/failure and an ageing fleet, stands out in the latest analysis of Lloyd’s List Intelligence casualty data.
The number of maritime casualties rose by 15% in 2024. Coupled with a 7% rise in casualties in 2023, this represents a concerning development for the maritime industry, partiularly with the global fleet growing at a considerably slower rate.
This trend has now been established for several years. While the overall number of incidents declined by 5% be- tween 2014 and 2018, the figure has increased every year since.
Between 2018 and 2024, the number of incidents increased by 42%. Over the same period, the number of vessels in the global fleet increased by 10%.
Casualty data, which is sourced from Lloyd’s List Intelligence, has been categorised under the following headings: collisions with another vessel, contact with a static object (e.g. harbour wall), fire/explosion, foundering (sunk or submerged), hull damage (hole, crack, or structural failure), machinery damage or failure (e.g. lost rudder, fouled propellor), piracy, war loss or damage during hostilities, and wrecked or stranded (aground).
Continuous increase in machinery failures boosts casualty rate
Machinery damage/failure has traditionally accounted for the largest portion of incidents. However, its share has increased significantly over the course of the past decade. In 2014, this accounted for 38% of all incidents but rose to 60% by 2024.
Machinery damage/failure is also the main driver of the sharp uptick in casualty numbers in 2024, accounting for 80% of incident growth.
While the reasons for these kinds of casualties are wide and varied, some key figures stand out from the statistics.
Top of the list is the ageing global fleet. In 2014, 36% of the global fleet was 25 years or older, with a further 7% in the 20- 24 years age category. In 2024, 44% of the global fleet was over 25 years old, with 9% in the 20-24 years age category.
Factors driving the ageing fleet and delayed vessel scrapping
A range of different factors are contributing to the ageing fleet. In recent years, there has been high demand for tonnage, with this translating into sky-high freight rates, particularly in 2024. Many shipowners are delaying the scrapping of vessels that would normally be decommissioned, opting to profit from these assets instead.
Other factors that are also at play are the new regulations from the IMO and EU on emissions and fuel efficiency.
These have made shipowners hesitant to invest in new- builds until they are more certain about what new fuels to adopt. Additionally, space in shipyards is limited and building costs are high, driving shipowners to focus on their existing assets, or else upgrade or retrofit these assets instead of replacing them.
Either way, the ageing global fleet is clearly having an impact on casualty statistics.
Over half (52%) of all incidents in 2024 were attributable to vessels 20 years of age or older, with 41% of incidents for vessels in the 25+ age category. In contrast, 41% of incidents in 2014 came from vessels over 20 years old, with 32% coming from the 25+ age category.
The statistics also show that the growth in incidents in 2024 is mainly being driven by the older portion of the fleet. In real terms, the number of casualties rose by 358 between 2023 and 2024. Some 285 of these incidents came from vessels over 25 years old, representing 80% of all incident growth. Of these, 236 (83%) were attributable to machinery damage/failure.
For machinery damage/failures, age is an even bigger fac- tor. In 2024, a total of 45% of these kinds came from vessels over 25 years of age, with a further 12% in the 20-24 age category. In 2014, the corresponding figures were 39% and 9%, respectively.
The ageing fleet is also a significant factor in the number of hull damages, which increased by 7% to reach 114 incidents in 2024. Some 46% of hull damages were attributable to vessels which were 20 years or older.
While the main way of reversing this trend will be a replacement of the ageing portion of the global fleet with new, modern vessels, some other short-term fixes can be ap- plied. More regular maintenance of vessels, and upgrades to equipment and parts can reduce the risk of casualties for these vessels, helping to prolong their lifespans in a way that is safer for the vessels, their crew, and the surrounding environment.
Urgent need for better fire safety
Of equal concern are the numbers of fire/explosions, which increased by 18% in 2024, and by 58% since 2014. As fire and explosions tend to have higher rates of injuries and fatalities and, with a disproportionately high amount (27%) coming from the passenger/ferry segment, this is a trend that needs to be quickly reversed. As a matter of high priori- ty, enhanced fire safety measures and emergency response training should be implemented on all vessels where this is deemed to be lacking.
Decline in collision, foundering, and piracy incidents but sharp increase in war losses
Putting these trends aside, the safety data does have some more promising stories to tell. Although the number of ‘accident’ casualties – a combination of collisions with another vessel, contact with a static object, foundering, and wrecked/stranded – slightly increased in 2024, the overall trend shows that this decreased from a total of 881 in 2014 to 656 in 2024, representing a decline of 26%.
This decline is likely attributable to technological advancements which have seen significant improvements to navigation systems, digital safety mechanisms, and route and weather planning over the past decade. Other factors, such as improved vessel design and engineering, stricter safety regulations, and data-driven risk management have also contributed.
Casualties involving piracy also fell in 2024, with the overall trend showing a 48% decline in these kinds of incidents be- tween 2014 and 2024. This is largely the result of sustained international cooperation over the past decade, which has led to improved maritime security practices, regional stabilization efforts, and the adoption of best management practices by shipping companies.
In contrast, however, war loss incidents increased with yearly numbers ranging from zero to three until 2021 to 51 in 2024 due to ongoing political conflicts. This underscores the impact of geopolitical instability on maritime safety, highlighting the vulnerability of maritime operations in conflict zones and how this can lead to increased risks for vessels, cargo, and crew.
Machinery damage/failure trend consistent across segments
Taking an even closer look, the safety data also shows the general trend towards machinery damage/failures affecting all types of ships, albeit with variations from segment to segment.
General cargo vessels have traditionally accounted for the biggest share of incidents, with this maintained in 2024 (26%).
Following two years of decline, the number increased again by 11% in 2024, reaching 739. The majority of casualties (57%) were attributable to machinery damage/ failure, with this metric increasing by 13% in 2024.
Passenger/ferry vessels saw a dramatic rise in machinery damage/failure in 2024, growing by 48% to 484. This segment also saw a significant increase in fire/explosion casualties, with this climbing to 48 in 2024. Overall, the passenger/ferry segment accounted for the second highest number of casualties in 2024, with this spiking by 29% to reach 672.
A notable increase was also registered in the RoRo/PCTC segment in 2024, where the number of incidents jumped by 69% to reach 311. This was overwhelmingly driven by an 87% rise in machinery damage/failures, which reached 251 by year end.
In the bulk carrier segment, growth in incidents was more subdued in 2024, increasing by just 2%, albeit this followed 14% growth in 2023. Bucking the overall trend, machinery damage/failures declined by 13% to 223 in 2024 , with this counteracted by growth in fire/explosion, hull damage, and piracy incidents.
Tanker segment casualties decline amid mixed trends in 2024
The number of incidents also grew by just 2% in the container segment in 2024, following declines of 7% in 2023 and 15% in 2022. This segment also saw a decline in machinery damage/failures in 2024 (10%), but growth in fire/ explosion, collision, and contact.
Tankers was the only segment which experienced a de- cline in incidents in 2024, with the overall figure dropping by 3% to 308. Despite an 11% increase in machinery damage/failures, declines were noted across most other metrics, particularly piracy (53%), fire/explosion (18%) and collision (20%).
Gas carriers had the same number of incidents in 2024 as 2023 (38), although this followed strong incident growth in 2023 (65%). Unlike most other segments, this benefitted from a 35% decline in machinery damage/failure incidents in 2024.
Shipowners and operators urged to take action to mitigate today’s and future risks
While there are some glimmers of positivity, the overall trend in maritime safety is unmistakably negative. A steadily ageing fleet is clearly driving an increase in the number of incidents, and it is incumbent on shipowners to mitigate this issue through better maintenance, or other means.
The adoption of new technologies and fuels is also likely to be a growing factor in the years ahead and this should be addressed from an early stage though the implementation of safe vessel designs, profound technical barriers, best practices and comprehensive, continuous training for all crew members.
The maritime industry is in the middle of a period of great transformation. While this offers significant promise, it is also full of uncertainty, and stakeholders across the industry should continue to adopt best practices in ensuring the safety of vessels and crew.
Key developments from recent IMO sessions on maritime safety
The IMO is making significant progress towards modernizing global maritime safety regulations, with new regulations that seek to enhance standards in order to accommodate new technologies and fuels, while making the maritime industry more adaptable and receptive to innovation
The complexity of maritime safety is evident from the wide variety of topics currently on the agenda of the International Maritime Organization (IMO) – some of which are highlighted below.
Propulsion and steering – from prescriptive requirements to a goal-based format
Current regulations around propulsion and steering are part of the Safety of Life at Sea (SOLAS) treaty, which was drafted when most vessels were powered by conventional engines and maneuvered by rudders. With so many other systems now available and in widespread use, work is underway to translate these existing requirements into a goal-based format that is suitable for all types of propulsion and steering – and which, we can presume, will also account for the wide variety of alternative fuels being introduced.
In its current form, SOLAS Chapter II-1 addresses traditional steering gear arrangements with a propulsion system and a rudder. Modern combined steering and propulsion systems (e.g. azimuth thrusters, waterjets) are, however, not addressed in the current regulatory framework, which is therefore seen as an obstacle to innovation.
The IMO is now working on a revision of SOLAS Chapter
II-1 that addresses both traditional and non-traditional pro- pulsion and steering systems. The new requirements will be goal-based and therefore naturally apply to all steering and propulsion system types. Crucially, they will be broader and more flexible than prescriptive regulations, outlining what needs to be achieved as opposed to how this should be achieved, allowing the IMO to define key safety criteria and leave the technical implementation to other stakeholders.
“A key benefit of goal-based requirements is that they pro- vide the industry with the flexibility to accept new technologies and novel designs by meeting broad safety requirements instead of specific design criteria,” says Kathrine Ilje Nerland, Senior Principal Engineer and safety regulation ex- pert at DNV. “In practice, this enables the maritime industry
to adopt new fuels or operating systems with total clarity on safety expectations, while avoiding strict constraints on their ability to innovate.”
Fire safety for containerships
An increased number of serious fires in the cargo area on containerships has exposed technical challenges related to locating, containing, and fighting fires on these vessels.
The IMO is considering measures for the detection and control of fires in container cargo areas. These measures include:
- Requirements for portable infrared thermal imagers, suitable for screening containers and detecting hot areas
•Requirements and performance standards for water mist lances, including means for extended reach of containers
•Requirements and performance standards for mobile water monitors and fixed water monitors
•Water protection systems below the hatch coaming and pontoon hatches
One important consideration is that any regulations on tackling fires should aim to minimize any risk of danger to crew. “It’s important that regulatory updates improve technical safety without introducing new challenges, balancing the need to tackle fires with prioritising crew safety and welfare,” explains Nerland.
Charging up electric vehicle transport
An increasing number of electric and new-energy vehicles are being carried on board ships. The IMO has agreed to consider if there are additional fire risks involved, for example related to the carriage of lithium-ion battery-powered vehicles.
Therefore, the IMO has developed an action plan to evaluate the adequacy of fire protection, detection, and extinction arrangements in vehicle, special category, and ro-ro spaces in order to reduce the fire risk of ships carrying new-energy vehicles. The action plan includes the analysis of reports, studies, and technologies; the identification of hazards; and the development of related goal-based measures.
Safe Return to Port (SRtP) progress
The Safe Return to Port (SRtP) concept was introduced in SOLAS in 2010 with the intention of increasing the robust- ness and fault tolerance of passenger ships. Even in the event of a flooding or fire incident, a ship should be able to return to port with its own machinery and provide a safe area for everyone on board. The SRtP regulations apply to passenger ships with a length of 120 metres or more, or with three or more main vertical zones.
The IMO is working on a revision of the “Interim Explanatory Notes for the Assessment of Passenger Ship Systems’ Capa- bilities After a Fire or Flooding Casualty” (MSC.1/Circ.1369) to facilitate uniform implementation of the concept, taking into account experience gained so far.
One of the key discussions revolves around the concept of remaining operational, particularly in terms of assessing
passenger ship systems’ capabilities after a fire or flooding incident and defining the criteria for what it means to stay operational.
Ensuring plain sailing for autonomous ships
The prospect of autonomous ships operating internation- ally with little or no human intervention has highlighted the need for a regulatory framework for such ships, including their interaction and co-existence with conventional manned ships.
The current regulatory framework generally assumes manning and human intervention. The IMO has agreed to first develop a non-mandatory, goal-based code, potentially entering into force as a mandatory code upon experience with its application. The purpose of the code is to provide a framework to address both the remote control and the autonomous operation of key functions of ships.
The chapters of the Maritime Autonomous Ships and Ship- ping (MASS) Code on risk assessment, remote operations, and connectivity are now nearing completion. The chapters on remote operation and connectivity will apply depending on the mode of operation and the functionality being applied.
The non-mandatory MASS Code is to be finalised by 2026, followed by an experience-building phase after its adoption. A mandatory code is expected to enter into force in 2032, at the earliest.
Prepare for change
DNV class customers are encouraged to visit the Compliance Planner to monitor how upcoming statutory requirements will impact their ships and subscribe to our Statutory newsletter sharing the main outcomes of safety relevant IMO meetings among others.
Technology Qualification: Facilitating safe maritime innovation
Technological innovation continues to drive the maritime industry forward, improving safety and driving decarbonization. However, many pioneering technologies face challenges in aligning with existing regulatory frameworks. DNV’s Technology Qualification process bridges the gap, as demonstrated by the Candela P-12 ferry.
Several completely novel technologies have emerged in shipping in recent years, increasing the energy efficiency of vessels or facilitating the use of alternative fuels. However, due to their novelty, many of these innovations operate beyond the confines of established regulatory frameworks. This creates uncertainty that can negatively impact the innovation process.
“Many shipowners are currently evaluating the adoption of novel technologies at different stages of readiness.
However, this introduces inherent risks concerning the effectiveness of energy efficiency measures and fosters uncertainty with respect to investment decisions,” says Carl Erik Høy-Petersen, Business Development Leader, Maritime Advisory at DNV.
The need for a different approach to support new technologies
These uncertainties have created a need for assurance in the development of novel technologies. With the Technology Qualification process, DNV Maritime Advisory provides clients with high-end consultancy throughout the innovation process, independent from its Class services.
“Technology is often far ahead of regulation in the maritime sector, so we need alternative approaches to ensure safe implementation of innovative technologies. This inspired Technology Qualification as a methodology and process
at DNV,” says Johan Iseskär, Principal Engineer, Maritime Advisory at DNV. “With this we have been able to qualify a variety of maritime technologies, such as fuel cells in cruise ships, propulsion systems, waste treatment systems, and the introduction of new ship fuels, among others.”
How does DNV’s Technology Qualification process work?
Technology Qualification (TQ) provides evidence that technology will function within specified limits with an accept- able level of confidence. In practical terms, this means that companies wanting to develop novel concepts will engage with DNV from the early stages of their innovation process to gain an independent evaluation of their technology.
DNV experts work closely with clients in developing a deep- er understanding of their technology, focusing on several different perspectives, such as safety, efficiency, operability, and profitability. The results provide the clients with insights into how their technology can fail at any stage of its journey, supporting them in establishing a more robust development, manufacturing, testing, and commissioning plan.
Identification of technical, compliance, safety or performance issues at the earliest possible point in the development process helps minimize cost and time of rework. This way the TQ process helps reduce the cost of qualifying new technologies and reduces time to market.
Iterative approach for social and economic realities
At the core of the TQ process is an iterative, systematic approach, which deals with each stage of the technological journey. This starts with an initial qualification basis, working through technology assessment and threat assessment (HAZID, FMECA), all the way through to qualification plan, qualification execution and performance assessment. If the technology is deemed to be below the required standards, practical recommendations will be made, usually resulting in alterations.
“As a main principle, we engage in close dialogue with our clients, leveraging their knowledge and expertise alongside that of our subject matter experts at DNV. Together, we systematically address challenges and uncertainties and identify inherent hazards in each technology,” says Iseskär. “This provides us with a high-level risk assessment, not only covering safety-related matters but also looking at other important aspects like efficiency, maintainability, profitability, public opinion, and environmental aspects. The holistic approach prepares the technology for social and economic realities.”
Candela P-12 developed with the TQ process
Candela is a prime example of an innovative organization which has benefitted from close partnership with DNV through the TQ process. For the past few years, the Swedish company has been developing the Candela P-12 ferry, based on hydrofoil technology, successfully launching the vessel towards the end of 2023.
Partnership with DNV through the TQ process has been a key part of the development of this unique vessel. “The TQ process is more detailed and comprehensive compared to standard type approvals for conventional vessels,” says Rasmus Kratz, Compliance Engineer at Candela. “While the risks with traditional boats are widely recognized and understood, the TQ process compelled us to meticulously assess and address the unique risks involved in constructing an electric hydrofoil vessel. This has ensured that the P-12 is designed to be an exceptionally safe watercraft.”
Advantages of hydrofoil technology
Hydrofoil technology – where a foil lifts the vessel up from the water as it gathers speed – has a range of benefits. “The key advantage is that the hydrofoil system reduces energy consumption by more than 90% compared to conventional diesel vessels, if one calculates savings from energy converted from battery/diesel to propulsion,” explains Kratz. “This in turn enables long range and high speed on battery power only – a first in the industry – and halves operational costs.”
Early partnership with DNV in TQ process
“Candela consulted DNV at an early stage of the development,” says Kristoffer Uulas, Senior Consultant, Maritime Advisory at DNV. “They had questions about safety and compliance but also about how to navigate the approval process for a new technology that doesn’t fit any of the currently existing rules.”
This early engagement with DNV experts provided Candela with the confidence that their concept was fundamentally sound, smoothing the path of further technological progress and development. “We moved from the general concept of the foiling technology through to HAZID challenges and uncertainties,” says Uulas. “This provided a solid basis for the qualification and further development of the technology.”
Using TQ process to ensure the P-12 will operate as intended
The identification of potential hazards and pitfalls through- out the TQ process often led to alterations to the originally planned technological pathway. Mitigation of potential risks and failure modes was ensured by executing the qualification plans, providing evidence through analyses and tests, and adding control measures in design, manufacturing installation, commissioning operation and maintenance. “Doing this has made the P-12 safe, robust, and prepared to deal with any challenges that it might face in the future,” says Iseskär.
There have been a lot of changes and iterations to the de- sign along the way and DNV has been a vital part in helping Candela navigate this map, providing evidence through the qualification plan,” adds Kratz.
Greater levels of safety and redundancy with TQ process
Clearly understanding the risk picture has helped the Swedish innovators to adjust the technology to achieve a higher level of safety and redundancy, beyond the initial plans. “Rather that merely aiming for compliance, Candela chose throughout the process to have more redundancy and more safety functionality than required. This has increased the vessel’s reliability, minimizing the risk of safety incidents or technical failures in the future,” explains Iseskär.
TQ process provides basis for future safety and operability
As the successful launch of the Candela P-12 prototypes in 2023 has shown, close cooperation with DNV through the TQ process provides a sound basis to assure future safety performance and operability, increasing the likelihood of vessels reaching full development stage, while also improving their future economic prospects.
Introducing a totally new type of vessel, which is significantly more sustainable than anything that has come be- fore, has been a complex process,” concludes Kratz. “Drawing on DNV’s experience and expertise through the TQ process and partnering with some of the foremost experts in marine safety has been invaluable to its development.”
Safe implementation of decarbonization technologies
With the shipping industry targeting zero emissions, this article reviews the safety considerations for different decarbonization technologies. It highlights the critical role of risk assessments, class approvals, and crew training in ensuring safe implementation and operation.
As the shipping industry prepares for a zero-emission future, owners are evaluating a variety of propulsion and onboard energy generation or optimization technologies to maximize energy and operational efficiency. These technologies are expected to remain relevant independently of the fuels used in the future, since all alternative fuels are expected to be costly.
Safety considerations should be part of every decision to adopt a particular technology or vessel modification. While some technical efficiency enhancements, such as propeller retrofits, passive air lubrication or hull modifications, typically do not influence the onboard routines, others, including wind-assisted propulsion systems (WAPS), shore power, battery systems, active air lubrication systems and alternative fuels introduce risks related to structural integrity and new procedures on board or changes to existing ones, which need to be accounted for.
Furthermore, most technical modifications require class approval. DNV class notations for many enhancements exist and are mandatory if relevant measures are implemented. For major retrofitting projects, a comprehensive risk assessment is generally advisable and, in many cases, required by class or the authorities, especially where the regulatory environment is incomplete.
Navigating a ship with active WAPS takes experience and skill and typically requires updates to onboard practices, safety protocols, maintenance routines, and equipment. Control systems for the propulsion engine and WAPS should be integrated to allow efficient coordination of both. Comprehensive crew training is essential to ensure safe and efficient WAPS and vessel operation.
DNV rules ST-0511 define structural design loads and associated safety concepts for WAPS for designers and manufacturers. The class notation “WAPS” is mandatory when installing WAPS on an ocean-going vessel. DNV offers its Approval in Principle (AIP), Type Approval Design Certificate (TADC), and Type Approval Certificate (TAC) as WAPS technology qualifications.
Air lubrication
Active air lubrication systems (ALS) on ships must meet stringent safety requirements to ensure safe and effective operation. These include approval by a classification society, structural assessments to account for hull modifications, and integration with ship stability calculations. Machinery components such as air compressors and piping must be marine-grade and equipped with over- pressure protection. Continuous monitoring, automatic shutdown features, and integration with the ship’s automation systems are essential for optimal performance. DNV has issued a recommended practice for establishing a standard for verification of the performance of air lubrication systems.
Hull and propeller cleaning
As one of the most straightforward efficiency enhancements, hull and propeller cleaning can either be performed during dry docking or during cargo operations in port where permitted. Conventional hull cleaning by divers involves several safety risks. Remotely-operated underwater vehicles (ROVs) equipped with high-pressure water or cavitation systems or hull cleaning through automatic collection of waste products, using specialized equipment to remove biofouling from the hull while simultaneously capturing debris, offer a non-destructive alternative to divers, eliminating the associated safety risks. However, ROVs cannot access certain areas of a ship hull, such as thruster tunnels, so some diver-assisted operations are still necessary. Some regions have mandated clean hulls and proper debris management based on the IMO Biofouling Guidelines, making compliance essential to prevent the spread of invasive species and protect marine ecosystems.
Wind shields
Installed for aerodynamic optimization, wind shields may have an impact on safety by compromising the line of sight from the bridge, or affecting ship stability. Modifications should follow DNV-RU-SHIP Pt.5 Ch.11. Class approval is required if modifications alter the structural integrity or primary safety features. Clear visibility must be maintained at all times, and defogging or heating systems should be functional in cold climates to prevent icing or fogging.
Batteries
Lithium-ion batteries introduce the risk of thermal runaway, which increases the fire, explosion, and toxicity risk on board the vessel. Safety measures such as thermal runaway propagation protection, sufficient ventilation, and fire sup- pression need to be implemented. The DNV class notations ‘Battery(Safety)’ is mandatory for installation of (li-ion) batteries larger than 20 kWh, while ‘Battery(Power)’ is required if the vessel depends on batteries for propulsion. Addition- ally, some flag states have guidance for battery installations that might be applicable.
Shore power
Under FuelEU Maritime, shore power will become mandatory from 1 January 2030 for containerships and passenger ships above 5,000 gross tonnage calling at EU ports. Connecting and disconnecting shore power cables can expose operators to electrocution risks and pose an explosion risk if flammable vapours are present. To mitigate these safety risks, operators should ensure that the electrical connection is not live (e.g., it has to be isolated and grounded) and wear appropriate personal protective equipment (PPE).
Ideally, shore power connections should be placed away from areas with flammable vapours. If this isn’t possible, ensure the environment is safe during both connection and operation. Additionally, implementing automatic disconnect systems and conducting regular safety training can further enhance safety. Interim guidelines issued by the IMO provide guidance and recommendations to enhance safety. The DNV class notation SHORE POWER includes a set of general requirements for shore power designed to be flexible. The IMO has issued MSC.1/Circ.1675, Interim Guidelines on the Safe Operation of Onshore Power Supply (OPS) Service in Port for Vessels Engaged on International Voyages. Port-specific safety requirements may apply in addition.
Dynamic positioning (DP) power system upgrades
Operation of DP systems is highly energy-intensive. Power system upgrades using closed bus-ties optimize energy usage and minimize carbon emissions from gensets through optimal battery use for peak shaving and load balancing. However, industry adoption of closed bus-ties has been hindered by concerns over failure propagation. To address this, DNV has revised its recommended practice (RP) RP-0591 for redundant dynamic positioning systems with closed bus-ties. New fuel-efficient designs must ensure sufficient safety for all planned DP operations by updating safety barriers, incorporating additional protection and monitoring facilities, and validating fault tolerance through rigorous testing.
Switching safely to low-carbon fuels and technologies
As the maritime industry shifts towards low-carbon fuels, ensuring safety during this transition is paramount. This article highlights the critical measures and considerations necessary for a safe and effective switch to low-carbon fuels and technologies.
Orderbooks are increasingly filled with LNG and methanol- fuelled vessels, as shipowners respond to current emissions regulations and aim to lower carbon intensity in the near term. However, with the IMO targeting net-zero greenhouse gas emissions by 2050, both LNG and methanol derived from fossil sources are expected to serve primarily as transitional fuels, requiring a further shift to low- or zero- carbon alternatives.
Preparing for future fuel switches and their risks
To support this transition, it is essential that considerations for future fuel flexibility are embedded from the design and newbuilding phase. This includes ensuring sufficient space and structural integration for alternative fuel systems, selecting materials compatible with a range of fuels to the extent possible, and designing fuel storage and supply systems that can be retrofitted with minimal disruption. Conducting high-level risk assessments early in the design phase can be an effective strategy to avoid potentially costly design changes later, depending on the extent of re-arrangement required.
Risk mitigation measures for liquefied gases such as hydrogen and ammonia typically include physical barriers between fuel storage, processing, and pumping equipment, and, to the extent possible, maintaining a distance from crew accommodation and workspaces. Detection systems for hazards such as gas leakages and fire are crucial safeguards to implement in relevant locations, enabling early warnings and the initiation of mitigating measures in case of occurrence. A practical and appropriate level of personal protective equipment (PPE) should be mandatory in hazardous areas.
Biofuels: Immediate alternatives with specific risks
From a safety and design perspective, enabling a future switch from conventional fossil fuels to biofuel involves practical and operational risks that need to be addressed to ensure compatibility of fuel systems with varying purity levels or slight differences in properties resulting from various production processes. Certain biofuels have a shorter shelf life compared to conventional marine fuels, which necessitates careful storage and handling considerations. For some biofuels there may be a need for additional training of crew with regard to handling.
Switching from LNG
While LNG addresses today’s challenges, the successful adoption of next-generation fuels depends on proactive planning and a design approach that anticipates both safe- ty and regulatory demands. As the industry looks towards fuels such as ammonia, hydrogen, and green methanol, safety must remain a top priority due to their unique risk
profiles – ammonia’s toxicity, hydrogen’s flammability and dispersion behaviour as well as its properties in both liquefied and compressed state, and methanol’s low flash point and near-invisible flame. Hydrogen is prone to leakage and can cause severe explosions when escaping. When stored in liquid form at ultra low temperature of -253°C, it requires sophisticated vacuum-insulated pressure tanks that must meet even stricter requirements than LNG tanks. Interaction of liquefied hydrogen with air or other gases harbours additional safety risks that must be considered in the design
of storage and processing systems. As an alternative to liquid storage, hydrogen may be stored in compressed form at very high pressure; here again, the containment system must meet strict requirements to reduce the likelihood of leakage.
Liquefied ammonia leakages may damage ship structures due to low-temperature embrittlement, likewise requiring suitable material choices for tanks, processing systems and their surroundings. Ammonia is also highly corrosive to certain types of commonly used construction materials, which has to be accounted for in material selection. The focus of the ship design should be on minimizing and mitigating ammonia releases.
Ensuring safe and prepared fuel transitions
Comprehensive risk assessments should be initiated early to guide technical decisions and ensure safe operations. These may include qualitative assessments like Hazard Identification (HAZID), Hazard and Operability studies (HAZOP), Failure Mode and Effects Analysis (FMEA), as well as quantitative studies like Quantitative Risk Assessment (QRA), Gas Dispersion Analysis (GDA) or Explosion Risk Analysis (ERA). It is also imperative that the organizations deciding to utilize alternative fuels evolve in parallel with the technical development, ensuring that aspects concerning crew training, operational procedures, and emergency preparedness all are ready to take on the transition to new fuels.
Switching from methanol
Methanol offers a relatively flexible platform for future fuel transition because it does not require cryogenic storage and can be handled with simpler infrastructure compared to LNG or hydrogen. Ships designed for conventional methanol from fossil sources can, with minimal technical modification, switch to green or blue methanol.
While retrofitting for green or blue methanol would not typically require major structural or system changes, continued compliance with evolving safety standards, emissions reporting, and certification frameworks must be factored in during the design phase.
Looking beyond methanol, a switch to even lower-emission fuels such as ammonia or hydrogen is technically more complex and would generally require significant redesigning of fuel storage, supply systems, and safety measures.
These fuels come with different physical properties and risk profiles, demanding tailored containment, ventilation, and fire suppression systems.
Available interim guidelines for ships using alternative fuels (methanol, ammonia and hydrogen (draft)) are all based on the safety principles of the IGF code (International Code of Safety for Ship Using Gases or Other Low-flashpoint Fuels) as a starting point. Until comprehensive statutory regulations are in place, an alternative design assessment for any alternative fuel project is essential. The IMO’s risk-based alternative design (ADA) process (MSC.1/Circ.1455) provides a basis for individual approvals (see page 22).
Onboard carbon capture and storage (OCCS)
Carbon dioxide (CO2) captured from the exhaust gas stream using chemical solvents is purified and compressed for onboard storage. While CO2 is classified as a dangerous good by the IMDG Code and has recently been classified as toxic by IMO, its risks can be effectively managed with proper safety measures. CO2 displaces oxygen in the air, posing a risk of asphyxiation or intoxication, which must be mitigated through adequate ventilation and monitoring systems. The solvents and refrigerants used in the liquefaction and storage of compressed CO2 also require careful handling. However, with relevant training, PPE and safety protocols, these risks can be minimized.
The installation of onboard carbon capture systems must adhere to strict guidelines covering exhaust pre-treatment, absorption processes, liquefaction, storage, and transfer systems. Regular maintenance and monitoring are crucial to prevent equipment failures and ensure the integrity of the capture and storage systems. Comprehensive crew training on the operation and emergency procedures related to OCC systems is essential to enhance safety and prepared- ness. These measures, combined with continuous regulatory updates and adherence to international safety standards, are vital for the successful deployment of onboard carbon capture technologies.
IMO plans to incorporate the application of onboard car- bon capture in the IMO Lifecycle Assessment (LCA) Guide- lines. DNV has published guidelines for the safe installation of onboard carbon capture, as well as comprehensive storage and classification rules, and offers its OCCS and OCCS Ready class notations. Flag state administrations have the final say on accepting these guidelines and may impose additional requirements for safe implementation on board.
Clearing the hurdles: approval of ammonia- or hydrogen fuelled ships
With the push for zero-emission shipping, ammonia and hydrogen gradually emerge as ship fuels due to their carbon-free emissions. These new fuels require a change of mindset in terms of design, operations, and crew competence, all addressed in a new DNV paper. With no specific IMO regulation available, the ADA process is essential for approval and the paper outlines how DNV rules provide structured, prescriptive requirements to simplify the ADA.
The approval process for ammonia- and hydrogen-fuelled ships is a critical step towards integrating these alternative fuels safely into maritime operations. But achieving approval through the International Maritime Organization’s (IMO) Alternative Design Approval (ADA) process involves navigating a complex regulatory landscape.
Seven steps to obtain approval
Linda Hammer, Principal Consultant, Environment Advisory at DNV, emphasizes the importance of a structured approach: “In a DNV paper, we outline seven steps to assist shipowners and other stakeholders in obtaining approval and safely deploying such ships in today’s immature regulatory environment. The regulatory path is certainly complex, but the steps and safety measures add up to a clear, achievable pathway to ship approval and safe operations. DNV’s tailored rule sets and learnings from pilot projects can significantly ease this process.”
Steps to obtain approval and safely deploy ammonia- or hydrogen-fuelled ships
Follow DNV’s prescriptive class rules and use them as the basis for ADA.
Engage early with Flag Administrations to align expectations and avoid delays.
Tap into DNV’s extensive and growing experience from prior projects to anticipate what risk studies and documentation may be needed.
Incorporate comprehensive safety measures in de- sign, particularly for leak prevention, gas dispersion, and personnel protection.
Update SMS systems and develop fuel-specific operational procedures.
Invest in training programmes until formal STCW courses are available.
Coordinate safe bunkering protocols and obtain necessary port approvals.
Understanding ADA phases
The IMO’s IGF Code (International Code of Safety for Ship Using Gases or Other Low-flashpoint Fuels) currently covers natural gas but not ammonia or hydrogen. Without detailed regulations, the IMO’s risk-based ADA process (MSC.1/ Circ.1455) is used. It involves demonstrating that the ship’s safety level is equivalent to that of conventional oil-fuelled vessels.
ADA has two main phases. A preliminary design approval requires a hazard identification (HAZID) study, developing a preliminary risk assessment, and defining preliminary risk-control measures and safety strategies.
Phase two, final design approval, starts with refining design with detailed technical and safety documentation then making a final risk assessment, addressing integration and operation-specific concerns. Then come complete system integration testing and submitting findings to the flag ad- ministration.
As the IMO regulatory framework progresses towards eventually amending the IGF Code, classification societies like DNV can give shipowners a head start in designing vessels by issuing class certificates and providing prescriptive rule frameworks to support ADA.
Simplifying ship approval: DNV’s Rules for ammonia and hydrogen fuels
Flag administrations enforce statutory regulations and have the final say on approvals. Early and active engagement with the relevant flag administration is crucial for clarifying approval expectations and streamlining the ADA process.
Subject to flag administration acceptance, the DNV rules can be applied as the flag administration’s approval basis or to significantly reduce the complexity of ADA.
DNV’s classification rules for ammonia and hydrogen, published in 2021 and 2024 respectively, provide structured requirements to reduce uncertainty in flag administration approval, streamline design focus, and offer predictability to shipowners, designers, and shipyards.
To obtain approval, shipowners should:
1.Engage early: Contact DNV and the flag administration early to clarify the approval basis.
2.Align design: Ensure the design aligns with DNV rules for a strong technical basis in risk evaluation.
3.Leverage experience: Utilize DNV’s experience from prior projects to anticipate necessary risk studies and documentation.
DNV’s ship rules also address the technical, human, and organizational risks associated with ammonia and hydrogen fuels, outlining requirements and mitigation systems for safe design and operation.
Addressing safety challenges in design and operations
Hydrogen is highly flammable, with wide explosive limits and low ignition energy.
Hydrogen storage involves cryogenic systems (−253°C) or high-pressure tanks (up to 700 bar).
Safety focus areas include preventing leaks through robust designs and secondary enclosures, ignition prevention, controlled gas dispersion from leakages, and personnel protection from frostbite and asphyxiation.
Ammonia is corrosive, toxic to inhale even in small concentrations, and can cause sever tissue damage upon contact. Safety focus areas discussed in the paper include preventing and detecting leaks, especially near accommodation areas; using ventilation, and toxic release mitigation strategies; designing safe bunkering systems and containment spaces; and providing personnel protection including safe haven.
Prepare for safe operations and crew competency
The safety challenges with hydrogen and ammonia also re- quire changes in ship operation, crew training, and possibly the organizational setup.
Safety Management System (SMS) updates must include fuel-specific operating procedures; maintenance protocols; and emergency preparedness and drills.
Training and competency development is hampered by the fact that there are currently no courses for ammonia or hydrogen under the STCW (International Convention on Standards of Training, Certification and Watchkeeping for Seafarers).
Coordinate safe bunkering and port approvals
Safety concerns extend beyond individual ships to the maritime industrial ecosystem within which they operate.
Unlike onboard fuel systems (regulated by the IGF Code), bunkering operations are governed by port, local, and national authorities. Each bunkering site requires site-specific risk assessments and dispersion analyses as well as harmonized procedures between ship and shore teams.
Adopting harmonized regional practices, as developed in studies by the European Maritime Safety Agency (EMSA) and MTF, can enhance safety. This approach could be realized through the development of a network of bunkering locations and green shipping corridors.
Collaborate to accelerate regulatory maturity
Industry-wide collaboration is essential, says Hammer: “The maritime industry cannot wait decades to mature these fuel systems as it did with liquefied natural gas. Rapid learning, pilot projects, and knowledge sharing are critical.”
DNV supports this through The Nordic Roadmap for Future Fuels; The MarHySafe hydrogen handbook; The Ammonia Safety Handbook published by the Green Shipping Pro- gramme; and engagements with EMSA to develop hydrogen guidance and training programs for hydrogen and ammonia.
Managing the safe use of ammonia as a marine fuel
As ammonia gains traction as a marine fuel, the focus on safe operation is growing. Safe ship design forms the foundation for safe operation, with DNV class rules setting requirements for these measures. However, crew training is also essential to effectively manage the risks associated with the safe use of ammonia, yet it cannot control the added risk of ammonia alone and technical barriers are also necessary. In collaboration with industry partners, DNV has developed a new recommended practice that outlines a clear framework for the safe use of ammonia as fuel.
Low-emission ammonia is increasingly recognized as a viable alternative fuel with significant potential to help the maritime industry decarbonize. Unlike conventional fuels, it has distinct characteristics that necessitate specific handling and safety protocols. However, with ship designs engineered to eliminate risks as much as possible, with proper training and a strong safety culture, its use can be effectively and safely managed.
“Ammonia is a chemical that deserves respect but should not be feared. This starts with a clear understanding of the hazard profile, both for ship design and safe handling,” says Laurent Ruhlmann, HESQ Vice President, Yara Clean Ammonia. The company handles 20% of all globally traded ammonia, produces more than eight million tonnes of
ammonia per year, and has a history of producing ammonia dating back to 1927.
Bridging the ammonia competence gap in maritime
“There is a lot of experience from handling ammonia on land for decades that can be easily ported over to the maritime world to help it meet the upcoming decarbonization targets,” Ruhlmann explains.
The maritime industry needs to embrace viable alternative fuels to successfully decarbonize. However, despite three ammonia-fuelled vessels already in operation and more than 30 currently on order (according to DNV’s Alternative Fuels Insight platform), specific training programmes for its safe handling as a marine fuel have been relatively slow to develop. This has created a growing competence gap, as existing training frameworks for alternative fuels like LNG do not adequately address the distinct properties and handling requirements of ammonia.
Maritime stakeholders shape ammonia safety practice
“Technical safety control measures incorporated into the ship, integrating human factors into the design process and technical class rules are the basis for managing safety risks in operation. However, the crew on board and the personnel ashore need to have competence in the technical safety barriers, how these can be maintained and knowledge and understanding of hazards and consequences if the safety barriers are degrading or failing,” explains Kirsten Strømsnes, Business Development Leader at DNV Maritime Advisory.
“Alternative fuel guidelines provide a strong foundation for safe adoption and handling of ammonia, but as a fuel it requires a dedicated framework and strategy tailored to its specific properties, such as its toxicity,” adds Erlend Erstad,
Senior Consultant, Safety, Risk & Reliability at DNV Maritime Advisory. Together with industry partners, DNV has developed a recommended practice (RP) to provide shipowners, operators and regulators with the structured approach needed to ensure competence readiness for ammonia-fuelled vessels.
“DNV’s RP assists shipowners and training institutions as they develop new marine fuel programmes based on its guidance and with input to reviewed safety protocols, risk assessment frameworks and crew training requirements. It was developed with input from a number of key stakeholders including Amon Maritime, Azane Fuel Solutions, Yara Clean Ammonia, Wärtsilä, Kongsberg Maritime and Bern- hard Schulte Shipmanagement/Ula Ship Management. This provided us with rounded and comprehensive best practice,” says Erstad, highlighting the benefits of close industry collaborations. “The RP is reflecting the specific systems on board, including technical safety barriers and technical classification rules.”
Learning from Yara’s leadership in ammonia safety
Yara Clean Ammonia was a key contributor to the RP’s development and has a strong safety culture. As a leader in ammonia production and handling, the company has de- cades of experience producing and transporting ammonia and operates the largest global ammonia network, with 15 vessels and access to 18 terminals worldwide.
“Yara Clean Ammonia’s extensive experience with the worldwide ammonia trade has helped shape the RP’s recommendations, particularly those regarding handling protocols, emergency response and risk assessment,” Strømsnes reports.
Ammonia growth: Safety key to drive future investments
Greater demand for ammonia as fuel could require expanding production, potentially doubling or tripling output within the next 20–30 years, making the need for specific ammonia fuel safety guidance even more urgent.
Safety incidents could severely impact industry confidence in ammonia as a fuel. To mitigate this, human factors must be integrated with technical design from the outset, and both human and operational considerations should be prioritized throughout the vessel’s life cycle. Shipowners must ensure they have the necessary expertise on board and adhere to best practices from industries that have safely handled ammonia for decades. “Ammonia is toxic, but this needs to be managed through technical barriers as the main foundation. Additionally, personnel need to be trained to have the necessary competence, and the safety management system must account for the new fuel and systems,” Erstad emphasizes.
The transition to ammonia requires a shift towards a risk- based approach, Ksenia Zakariyya, HESQ Manager at Yara Clean Ammonia, says. “To ensure safe ship design and operations, dedicated risk assessments are essential for enhanced decision-making and the definition of technical, operational and organizational barriers to effectively control risks throughout the asset’s life cycle. Understanding ammonia’s hazardous profile is crucial for responsible handling. Ship operators must develop ammonia-specific competence and training programmes to address its unique safety requirements. Emergency response plans should
be based on credible risk scenarios and tailored response strategies. Our experience demonstrates that with proper precautions in place, ammonia can be a safe marine fuel.”
The role of training institutions and flag states
With the RP, training institutions and the rest of the global maritime industry will now have a clear roadmap for developing concrete ammonia-specific training courses. The goal is to ensure that all crew members operating ammonia-fuelled vessels have the necessary competence for safe handling and use, ensuring that seafarers receive quality, standardized training that meets industry best practices.
The RP can also be used as input to competence planning and operational manuals as well as for reviewing safety management systems. It can also be used by third parties for certifying training programmes.
Flag states also have a key role to play as they currently need to approve the readiness of operations, including competence, before vessels with new fuels, following the alternative design approach, set sail. By endorsing the RP and referencing it in their guidance to shipowners, they can help drive the widespread adoption of ammonia safety standards in a more systematic way instead of case by case/ vessel by vessel. This alignment will be crucial as the maritime sector moves towards integrating ammonia into global shipping operations.
Ammonia safety: What maritime can learn from the chemical industry
Yara’s Ruhlmann highlights that the chemical industry has had a strict regulatory framework in place for almost 50 years. This has supported a proactive approach in developing very robust safety management systems and practices which maritime can learn from and incorporate into its highly regulated framework. In the past decades, significant safety incidents with ammonia have occurred in its downstream usage where safety management systems and best industry practices are less developed. While onshore applications may face different challenges, the maritime industry has the unique advantage of being able to incorporate robust safety measures and recognized good practices from the very beginning when using ammonia.
“While ammonia presents certain challenges, shipowners and operators can confidently integrate it into their operations by implementing structured safety protocols, clear regulatory guidance and comprehensive crew training,” ex- plains Ruhlmann. “Seafarers must receive ammonia-specific instruction, covering safe handling, emergency response and maintenance procedures. Regular simulated emergency drills and credible scenario-based training should also become standard practice to ensure operational safety and preparedness.”
The future of ammonia in maritime
“Ammonia must be treated with respect as a fuel, which means ensuring safe ship designs and implementing necessary technical barriers, fostering a proactive safety culture, and identifying small deviations or failures early — before they escalate into incidents. For many it is a different mindset, but we have to come around to using ammonia as a fuel,” Strømsnes concludes.
Regulations and safety frameworks will define the future use of ammonia-powered vessels. An industry-wide collaboration involving ammonia producers, regulators and vessel operators is critical for a safe transition, as shipowners will ultimately be responsible for implementing it on board vessels as shipping complies with internationally agreed decarbonization targets set by IMO.
Ensuring the safety of autonomous shipping
With autonomous shipping technologies advancing rapidly, maintaining the highest safety standards is essential. In January 2025, DNV’s Autonomous and Remotely Operated Ships (AROS) notations took effect, providing a framework for autoremote vessels to achieve safety levels equivalent to or higher than conventional ships.
The AROS notations are broad and comprehensive. The scope of the rules is to define systematics and functional and procedural requirements for autoremote vessels and systems used on board and off-ship. This extends to the re- mote operating centre (ROC) and the connectivity needed for autoremote vessel operations.
Autonomous shipping can be defined by three dimensions: location of control, [degree of] human involvement and degree of system independence. DNV divides each of these dimensions into four broad categories – remote control, decision support, supervised autonomy, and full autonomy – which can be controlled from various locations. These categories can be applied to different functional areas: navigation, engineering, safety, and operations.
Defining autonomous shipping in different ways
These dimensions and categories define the concept of autonomy in different ways. Remote control refers to vessels where operations are carried out at locations other than the vessel, while decision support refers to onboard systems which act like a “co-pilot”, analysing information and generating advice which is fed to an operator, who can then decide whether to act on this advice or not.
While remote control and decision support will always have human beings at the centre of the decision-making process,
this begins to deviate significantly with the other categories. Supervised autonomy has similarities to decision support, but the system can act and make decisions without waiting for acknowledgement from a human. Nonetheless, a human operator is informed about the system’s intentions in real time and can stop or override when necessary, something which only happens in exceptional circumstances in the case of full autonomy.
“The AROS notations acknowledge these different modes of operation, and these are central to their structure,” says Mariah Kurtinaitis Joukes, Autonomous Shipping Senior Engineer at DNV.
Safety at the heart of the AROS notations
At the heart of the AROS notations is the need to verify autonomous vessels as being as safe or safer than convention- al vessels. “While humans are often the cause of incidents on conventional vessels, they can also prevent smaller incidents becoming catastrophes,” says Are Jørgensen, Senior Principal Engineer, Digital Ship Systems at DNV. “So, in order to improve safety, we need the autonomous systems to be very robust and resilient.
“This is where we are trying to get to, and it is central to the framework that we have established with the AROS notations.”
Lightly regulated autonomous shipping
Autonomous shipping is still a lightly regulated space. IMO is currently addressing this by developing a code for Mari- time Autonomous Surface Ships (MASS) – a definition which aligns with DNV’s definition of “autonomous and remotely operated vessels”. MASS is expected to be voluntarily applicable from 2026, but not mandatory until 2032. Without regulation, the development of autonomous vessels has up to now been based on a broader, more abstract risk-based approach, applying guidelines from IMO Resolution 1455.
“This basically means that if there are no existing rules to follow, you then need to describe what you want to do, identify the associated risk and then take actions to de-risk,” says Joukes. “At DNV, we have been acting as a third-party verifier on a number of autonomy projects, based on this risk-based approach, and this has given us important knowledge which we have used to structure the AROS notations.”
Building on the DNV guidelines
“There are two parts to the notations,” says Joukes. “One part is that it requires clients to follow a risked-based process, which has already been described in DNV guide- lines for autonomous shipping, and the second is based on functional requirements.”
For this risk-based element, the AROS notations are based on DNV’s process-oriented guideline for autonomous shipping (DNV-CG-0264), first introduced in 2018 and now updated with lessons learned from earlier projects. Importantly, this contains process descriptions for both concept qualification and system qualification. Both are systematic risk-based assessments used in the development of novel technologies that ensure these technologies are safe, reliable and ready for market.
According to Jørgensen, going through these processes is a central part of the journey for developers of autonomous vessels wishing to be awarded the AROS notations. “While the notations apply some specific requirements, the nature of autonomous ships means there are many novel concepts which cannot be fully covered by requirements, particularly as we expect many innovations and technological developments in the future. This is why the risk-based approach is such a key part of the notations. It is not prescriptive in nature and is deliberately broad.”
Using previous experience
Based on previous experience in applying the risk-based approach, three things have been fundamental in creating the AROS notations.
Firstly, some patterns have emerged regarding functionality, and this has been very important in gaining a better under- standing of how autonomous ships operate.
Experience has also taught the project team to carry out a better and more structured risk analysis. This led to more focus on the follow-up of identified risks to ensure that these are mitigated in a good and traceable way.
Identifying the need for a flexible approach has also been crucial. This creates the option for DNV to carry out a safety evaluation of pilot test phases in the overall process. “In some cases, the concept owner or system supplier doesn’t really know what they’re going to do until they have tried and failed a bit. This allows them to try and fail in a safe way,” says Jørgensen.
Development of key functional requirements
Taking the knowledge and experience of working on autonomous projects, and identifying key patterns, DNV has developed some key functional requirements for autonomous ships, the second main pillar in the AROS notations. These complement the risk-based approach by drawing some lines in the sand with some fundamental rules.
“These functional requirements vary, depending on each system and which kind of notation is being sought,” says Joukes. “Generally though, this includes the expectation that vessels holding the AROS notations will be able to respond to abnormal events, and the requirement that vessels can monitor and respond to incidents which can result in harm to people, the environment or the vessel itself.”
Like the risk-based approach, these rules are expected to evolve in step with developments in the autonomous ship- ping space.
Safety at the heart of DNV’s outlook on autonomous shipping
DNV has been a pioneer in autonomous shipping for a number of years, with key involvement in flagship projects like Yara Birkeland, Reach Remote, and Ocean Infinity. Like everything, DNV’s continuing involvement in the space
is primarily driven by the goal that the maritime industry continues to evolve and innovate in a way that is safe and secure.
“As a class society we have no desire to push autonomy for the sake of autonomy,” says Joukes. “But if our customers are going in that direction, we should be able to help them and make sure that this is done in a safe way.
“That is our mission in class.”
Cybersecurity in autonomous shipping
Digital transformation and autonomy in shipping are also making cybersecurity a top priority. This article explores the cyber risks for autonomous and remotely controlled ships and how to integrate cybersecurity from the design phase to ensure safe and secure operations.
The increasing digitalization of the maritime industry is unlocking a range of new opportunities, helping to drive decarbonization efforts. Survey respondents of DNV’s 2024 Maritime Cyber Priority report point to advanced data analytics, the internet of things, AI and machine learning, high-bandwidth satellite communications, and autonomous operations as presenting the greatest opportunities for their businesses in the coming years. However, this is also creating more opportunities for cyber criminals.
While increased digitalization and connectivity make shipping companies more vulnerable to cyberattacks, this is unlikely to be a reason for them to slow down on their digitalization journey. In fact, the majority (61%) of maritime professionals believe the industry should accept increased cyber risk from digitalization if it enables innovation and new technologies. This acceptance is 10% higher than in other comparable industries.
Unique cyberthreats to autonomous and remote operations
Autonomous and remote-operated vessels depend heavily on integrated information and communication technologies (ICT) for navigation, propulsion, and communication. This dependence makes them particularly vulnerable to cyberthreats. Potential risks include unauthorized access to control systems, GPS spoofing, and data manipulation, all of which could lead to loss of control, collisions, or environ- mental disasters.
Because autonomous ships reduce or eliminate onboard crew, the ability to respond in real-time to cyber incidents becomes limited. Unlike conventional vessels, where engineers or captains can manually override faulty systems or secure communications, autonomous ships rely almost entirely on secure-by-design systems and robust remote operations.
Integrating cybersecurity from the design phase
Experts recommend involving cybersecurity professionals early in newbuild projects to safely integrate new technology. However, this practice is not yet widespread, causing issues at a later stage.
“The failure to incorporate cybersecurity into the early stage of new projects and initiatives leaves the industry scrambling to address the problem later on,” warns Svante Einarsson, Head of Maritime Cyber Security Advisory at DNV Cyber. “Retrofitting security measures is also more time-consuming and costly than embracing security by design.”
Embedding cybersecurity into ship design also ensures compliance with the International Association of Classification Societies (IACS) Unified Requirements E26 and E27, which focus on system integration and essential onboard systems, respectively. These requirements, mandatory for new builds contracted from July 2024, aim to create a robust cybersecurity framework for the maritime industry.
“The IACS Unified Requirements will ensure that cybersecurity is well-handled as part of the design verification during the building phase,” explains Jarle Coll Blomhoff, Head of Section Digital Ship Systems – Ship Classification at DNV. “System suppliers need to engineer strong cybersecurity resilience into their systems, and yards and designers need to have cybersecurity on their priority list when they order and integrate systems and design the overall vessel network. Addressing this is becoming a ticket to trade in the maritime industry.”
Design-phase integration includes mapping out all digital interfaces, defining access controls, and identifying where cyber vulnerabilities may emerge in the ship’s operating logic, data flow, or communication channels.
Cybersecurity in DNV’s AROS notation
Cybersecurity is also a fundamental and mandatory com- ponent of DNV’s AROS notation (see page 28). Vessels assigned to the AROS notation are required to either com- ply with DNV’s Cyber Secure class notation or demonstrate equivalent cyber risk controls, with particular emphasis on protecting autonomy-critical functions and ensuring the integrity and resilience of communication links.
DNV’s Cyber Secure class notation covers both the design and operational aspects of cybersecurity. It assesses system and vessel network design, shore connectivity, and extends into the operational phase, including crew and ship management procedures. Beyond technical requirements, it mandates that owners submit a cybersecurity management system for approval within three months after delivery. To ensure continued compliance, DNV surveyors go on board annually to verify that procedures are implemented and followed – bringing operational oversight in line with the spirit of the IMO’s ISM Code. The notation provides clear guidance and assurance of robust cyber risk management, while ensuring compliance with IACS Unified Requirements.
The interplay of regulation and innovation
Beyond IACS and classification guidelines, the International Maritime Organization (IMO) has underscored the importance of cyber risk management by integrating it into the International Safety Management (ISM) Code. This regulatory push ensures that cybersecurity is not just a design issue but a continuous operational requirement.
That’s particularly important for autonomous vessels, which are often in a legal grey area when it comes to current maritime regulations. In the absence of specific IMO guidelines for fully autonomous operations, applying best practices in cyber resilience becomes a proactive step toward compliance and operational readiness.
Furthermore, as shipowners look to adopt autonomous functions incrementally – starting with automated navigation or remote engine diagnostics, cybersecurity frameworks help bridge the transition from traditional to fully digital operations.
Operational challenges and the need for vigilance
The operational phase of autonomous vessels presents ongoing cybersecurity challenges. Continuous monitoring, regular software updates, and remote operation center staff and maintenance engineer training are vital to maintaining a secure environment. Given the dynamic nature of cyber- threats, a proactive approach involving regular risk assessments and incident response planning is crucial.
One of the key concerns during operations is real-time threat detection. Since the crew is not onboard to observe vessel behavior, real-time monitoring of security events and network activity is essential to detect and respond to potential breaches. Cyber hygiene is equally important on the shore side. Control center personnel must follow strict protocols to prevent unintentional breaches, including phishing, improper device usage, or misconfigured access rights since there is a potential risk the incident will spread to the vessels.
The human element behind autonomy
Despite the technology, humans remain an essential part of autonomous vessel safety. From the software engineers writing control algorithms to the operators overseeing fleets from land, the human element can be either a safe- guard, or a vulnerability.
Training is critical. Cybersecurity awareness must go be- yond IT departments to include all staff interacting with vessel systems. Just as seafarers are trained in fire safety and emergency procedures, shore-based personnel managing autonomous fleets should be trained to recognize cyber- threats and respond effectively.
Organizational culture also plays a role. If cybersecurity is viewed as a compliance checkbox rather than a shared
responsibility, vulnerabilities can be overlooked. Cultivating a culture where digital safety is treated with the same seriousness as physical safety is crucial in this new maritime era.
A new era of safety
The success of autonomous shipping doesn’t rest solely on cutting-edge AI or advanced navigation, it depends equally on how well the systems are protected from invisible threats. Cybersecurity isn’t just a technical requirement; it’s the invisible anchor that keeps autonomy grounded in safety.
Autonomous vessels offer remarkable potential: increased efficiency, fewer human errors, and new operational models. But without robust, integrated, and evolving cybersecurity measures, this potential remains fragile. As the industry navigates toward greater autonomy, ensuring cyber resilience must be a top priority, not just for classification compliance, but for the future of safe, reliable shipping.
DNV cybersecurity expertise is expanding rapidly
In 2024, DNV expanded its cybersecurity capabilities by merging with specialist firms Nixu and Applied Risk to form DNV Cyber. The addition of CyberOwl, a provider of vessel cyber risk monitoring and management solutions, further strengthened this move, bringing together over 550 experts in IT and OT security. For the maritime sector, this marks a step change in managing cyber risks, combining deep industry insight with advanced cyber expertise to safeguard vessels, infrastructure, and digital operations.
Within ship classification, DNV has established a dedicated cybersecurity team and is training hundreds of surveyors to support shipyards, suppliers, and vessels in safe and cyber secure operation around the world.
Shore leave is critical to safe shipping. So why don’t we treat it as such?
Every day, 1.89 million men and women work on board over 60,000 commercial vessels, quietly and all too often invisibly keeping global trade flowing. These seafarers live and work in some of the most isolated and high pressurized environments on earth. Their labours might sustain economies and underpin our daily lives, but the conditions they endure are mentally and physically demanding and, at times, deeply damaging.
For more than 160 years, The Mission to Seafarers (MtS) has been dedicated to supporting the people at the heart of our industry. We operate in more than 200 ports, spanning 50 countries, and deliver frontline care to those whose work is physically challenging, emotionally taxing and all too often overlooked. Our welfare teams are available 365 days a year, offering everything from pastoral ship visits and emergency assistance, to communication, transport and vital mental health and wellbeing resources.
Away from the ports, our programme work includes establishing family support networks in the Philippines, Myanmar, and India, providing training in suicide awareness and educating seafarers in financial literacy and good cross-cultural communication. We also shine a light on the lives of those on board via the Seafarers Happiness Index. As I reflect
on the findings we have reported, one truth consistently emerges: the absence of meaningful shore leave is having a corrosive effect on seafarers’ mental health and wellbeing.
The Seafarers Happiness Index is now in its tenth year, and the concept is simple: to collect and amplify the voices of those at sea. Each year, thousands of anonymous responses provide a sobering insight into the daily lives of seafarers. The questions we ask are constant and consistent, enquiring as to general levels of satisfaction, happiness with on board food, connectivity, training, and access to shore leave. We also turn the mirror on ourselves and ask about seafarers’ welfare which helps us to assess and continually improve our services.
In the latest report (Q1, 2025), there has been a slight uptick in overall happiness, rising to 6.98 out of 10. But whilst there are signs for hope, there remain persistent and systematic challenges which are fundamentally undermining the wellbeing of seafarers and could easily spark a significant safety issue.
Among the most pressing concerns of which seafarers speak are mental fatigue, lack of shore leave and excessive workload. As one seafarer puts it: “No more shore leave now. We stay on the ship every time for months. Before was different. Now everything is a rush” (sic).
This isn’t an isolated frustration. Shore leave scored just 6.73 in the recent Index – an improvement on the previous quarter but still among the lowest-ranking aspects of life on board. For many seafarers, particularly those on vessels with short turnaround times, the opportunity has vanished almost entirely.
Shore leave is not a luxury; it is a critical part of a good safety management plan. It provides physical rest, emotion- al relief, and a temporary escape from the confined, often stressful environment aboard ship. When seafarers are kept on board, we alienate them from the real world, and feelings of isolation are exacerbated.
This relentless pressure is not only inhumane, it’s dangerous. Mental health struggles can lead to decreased alert- ness, poor decision-making, and even suicidal ideation. A burned-out crew is not a safe crew. According to the 2023 report on maritime safety trends, 80 per cent of maritime accidents stem from human error. Reducing that statistic requires more than just a new safety culture. It demands a fundamental change of mindset. Seafarers must no longer be viewed solely as an operational resource but recognised as human beings with complex emotional, psychological, and physical needs.
The Seafarers Happiness Index notes that limited or non-existent shore leave contributes directly to feelings of entrapment, homesickness, and fatigue. What’s more, the burden of managing these conditions is often unevenly distributed. Junior officers and cadets may be better insulated by structured learning and lighter duties. Meanwhile, senior crew face the pressures of maintaining ageing systems and grappling with the steep learning curves of innovative technology, all while lacking the rest and recovery they need ashore.
Imagine turning up to work one day and your boss announces that no one is going to leave again for eleven months. Board and lodgings will be provided in the conference room, but you’ll be expected at your desk on a six hours on/off rotation over a 24hr period. What’s that? You want to pop to the shops for an hour or so? Forget it, there’s too much to do. Want to call your kids? Sure, but do it in your rest time.
Professionals ashore wouldn’t stand for it, so why should seafarers?
In the absence of consistent shore access, the maritime welfare sector becomes an invaluable resource. The global network of MtS supports over 500,000 seafarers and their families every year. Across our in-port network, we visited over 48,000 vessels, offering practical assistance, access to Wi-Fi and for those who could come ashore, a place to relax. More importantly, we offered human connection – a listening ear and a sense of normality amid an abnormal landscape of steel structures, containers, and remote berths.
Our welfare teams work in close partnership with local authorities and maritime regulators to assist abandoned crews – those left without food, water, wages or means of returning home. Last year, in the UAE alone, we supported more than 40 justice and welfare cases. Across the world, our Family Support Networks provide vital assistance to sea- farers’ loved ones, offering counselling, financial education, and community building.
We also offer digital support. Our Happy@Sea app, sponsored by DNV, Cargill, and the Seafarers’ Charity, enables crews to locate Flying Angel centres, connect with welfare teams and pre-order services such as transportation or items of shopping. They can also access our WeCare Financial Wellbeing and Social Wellbeing courses – two areas which are frequently highlighted in the Happiness Index as major stressors.
Recently, there has been much fanfare over the “key work- er” status afforded to seafarers in the amended Maritime Labour Convention. Such status is laudable, but it must be followed by robust action. Such initiatives could include:
1.Mandatory shore leave: Regulation should be enforced to make sure seafarers get adequate time away from the ship. A ship’s schedule should be reimagined to reflect the welfare needs of its crew, not the demands of an owner/ charterer.
2.Improved port infrastructure: Ports do not make it easy for seafarers to get ashore. We need safe, affordable, and accessible transportation from vessels to shore-based centres, even in high-security environments and anchorages.
3.Recognize the mental health imperative: Seafarers’ mental health should be a key performance and safety indicator, with adequate infrastructure in place to support every individual.
4.Enhance relationships with the maritime welfare sector: It is becoming increasingly difficult for welfare teams to get on to vessels and therefore to support seafarers.
The maritime industry is in the midst of extraordinary, fast- paced change: digitalization, decarbonization and geopolitical disruption are reshaping how goods are moved around the world. But no change will be successful unless we take care of heart of the industry: seafarers.
That means building a culture where shore leave is not an afterthought, but a basic expectation. Where every port welcomes seafarers not only as “key workers” but as people.
Where mental health support is embedded in safety, and where welfare organisations are empowered to do what we do best: meet seafarers with compassion, care, and practical assistance, wherever they are in the world.
Source: DNV
