The two dominant modes are helicopters and offshore vessels. Helicopters are typically used for routine crew changes, urgent maintenance support and medical evacuation over longer distances, because they are fast and largely independent of sea state. Marine options include platform supply vessels, fast crew boats, crew transfer vessels and multipurpose support vessels, which can transfer people either directly to the installation or via personnel baskets, gangways or ladders. The chosen mode depends on distance from shore, metocean conditions, available landing facilities, national regulations and cost. In practice, operators often combine both: helicopters for regular crew changes and vessels for construction, maintenance campaigns and short-range transfers. Reference: UK HSE – Offshore helicopter safety
Helicopters carry most routine crew changes in many oil and gas provinces. Flights are planned from onshore heliports to helidecks on fixed platforms, FPSOs and mobile units, often following weekly or fortnightly crew-change patterns. Regulators set requirements for airworthiness, pilot licensing and passenger safety equipment, while offshore regulators specify training in helicopter underwater escape, survival suits and briefings. Industry bodies such as IOGP and national associations publish recommended practices covering flight planning, fuel reserves, weather minima, seating configurations and emergency response. Operators then translate these into local procedures and contractual requirements for helicopter providers to ensure consistent safety standards across all assets in a basin. Reference: IOGP – Offshore Helicopter Recommended Practices
Fast crew boats (FCBs) and crew transfer vessels (CTVs) are high-speed craft designed to bring personnel and light cargo from shore bases to offshore installations. Built mainly in aluminium and optimised for speed and manoeuvrability, they can cover long distances quickly while maintaining acceptable comfort in moderate sea states. In oil and gas, they often support nearshore platforms and FPSOs; in offshore wind, they are standard for accessing turbines close to shore. Typical designs include monohulls, catamarans and SWATH hulls, with cruising speeds around 20–30 knots. Compared with helicopters, they are slower but cheaper per seat and can carry more tools and spare parts, making them attractive for frequent, short-to-medium range trips. Reference: USCG – Types of Offshore Supply Vessels: Crew Transfer Vessels
Platform Supply Vessels (PSVs) are primarily designed to carry bulk cargo, fuel, drilling fluids and deck loads to platforms and FPSOs, but they also transport a limited number of offshore workers. Personnel usually embark and disembark in port, then remain on board during offshore cargo operations, with transfers to the installation performed only when necessary and under controlled conditions. PSVs have accommodation spaces, lifesaving appliances and manning levels that comply with passenger and crew regulations. Their main contribution to personnel logistics is indirect: by resupplying installations, they enable smaller dedicated crew boats or helicopters to focus purely on people movement, while PSVs themselves may be used for opportunistic transfers or emergency evacuation if properly equipped and authorised.
Reference: USCG – Types of Offshore Supply Vessels
Personnel baskets are crane-lifted devices that allow small groups of workers to move between a vessel and an offshore installation when other means are unavailable or impractical. The basket, suspended from the platform or vessel crane, is carefully manoeuvred to the deck where passengers step on or off during a lull in relative motion. This method is often used on traditional oil and gas platforms or FPSOs without walk-to-work gangways, particularly in benign conditions or where ladders are not feasible for less fit personnel. Because crane transfers introduce risks of collision, swinging, crushing and immersion, industry guidance emphasises strict weather limits, competent crane operators, thorough risk assessments, inspections and specialist passenger training. Reference: Reflex Marine – Offshore Personnel Transfer by Crane Guidelines
Walk-to-work (W2W) gangways are motion-compensated bridges connecting a vessel to a fixed or floating installation, allowing personnel to step directly between them. Mounted on service or construction support vessels with dynamic positioning, these gangways actively adjust for heave, roll and pitch to keep the tip steady on the landing point. For platforms, FPSOs and substations, they provide a safer, less physically demanding alternative to ladders or baskets, especially for technicians carrying tools. They are often used during maintenance campaigns or extended projects, when many transfers are needed in marginal conditions. Industry guidelines treat W2W as one option in a wider personnel transfer toolbox, with a specific focus on operational envelopes, interface procedures and emergency recovery plans.
Reference: G+ – Good Practice Guideline: Offshore Wind Farm Transfer
Daughter craft and fast rescue craft are small boats deployed from a larger “mother” vessel to reach nearby installations or work sites. In oil and gas and offshore wind, they may be used to transfer a few technicians from a Service Operation Vessel or construction vessel to turbines, platforms or subsea work locations within a limited radius. Their advantages include flexibility, low mobilisation time and the ability to access tight spaces or shallow waters. However, they also face challenges: exposure to waves, limited shelter, and a higher risk when personnel embark or disembark alongside structures. Guidance documents therefore emphasise clear operating limits, robust launch and recovery systems and careful coordination between the mother vessel and the craft. Reference: ClassNK – Safe Operation of Daughter Craft
Tactical helicopter planning balances seat demand, flight time, fuel, weather and regulatory constraints across multiple installations. Planners build weekly or daily flight schedules from a hub heliport, grouping passengers to minimise helicopter hours while respecting maximum duty times and legal payload limits. Modern approaches use optimisation models to sequence landings and determine the best route to visit several platforms or FPSOs within a single rotation. Sensitivity to disruptions is critical: poor weather, technical issues or medevacs can rapidly change priorities. Recent research on the Norwegian Continental Shelf shows how mathematical optimisation can reduce costs and emissions while maintaining service levels, by adapting flight frequencies, aircraft types and routing patterns to a stable but complex demand profile. Reference: MDPI – Tactical Helicopter Transportation Planning for Offshore Installations
Weather and sea-state limits are central to deciding whether a marine crew transfer can proceed. Operators define the maximum significant wave height, wind speed, current, and visibility for each transfer method, based on vessel capability, transfer system design, and crew competence. For example, crew transfer vessels, daughter craft, baskets and W2W gangways each have different certified operating envelopes. Good-practice guidelines require a formal risk assessment, real-time monitoring of conditions and clear stop-work authority for the master or transfer supervisor if limits are approached. These thresholds are regularly reviewed using operational experience, incident data and technology improvements, with the overall aim of ensuring that transfer risks remain as low as reasonably practicable without unduly constraining offshore operations. Reference: IMCA – Guidance on the Transfer of Personnel to and from Offshore Vessels and Structures
Offshore passengers undergo mandatory safety training before using helicopters or marine transfers. Typical elements include basic offshore safety induction, sea survival, helicopter underwater escape, firefighting and first aid, often delivered under national training schemes. For marine transfers, additional instruction covers embarkation methods, basket or gangway procedures and emergency drills. Personal protective equipment usually comprises an immersion or transportation suit, lifejacket, hard hat with chinstrap, gloves and appropriate footwear, with additional harnesses or fall-arrest devices for certain transfers. Regulatory guidance and industry associations mandate refresher intervals, crew competence assessments, and toolbox talks before each operation, ensuring everyone understands site-specific hazards and their role in maintaining a safe transfer environment. Reference: C-NLOPB – Transportation by Helicopter to or from a Workplace in the Offshore Petroleum Industry
Dynamic positioning systems use thrusters, propellers, GPS and motion sensors to keep a vessel automatically on station without anchors. During personnel transfers to platforms, FPSOs or turbines, DP allows the vessel to maintain a steady relative position and heading, which is essential for safe gangway operations, daughter-craft launch and recovery, or crane transfers. Higher-class DP systems (DP2 or DP3) provide redundancy so that a single failure does not lead to loss of position. This reliability is especially important near subsea infrastructure or when connected to an installation. Classification societies and flag states specify design, testing and operational requirements for DP vessels, while operators define watchkeeping, capability plots and operating limits as part of their marine assurance processes. Reference: Boskalis – Diving Support Vessels (DP-2/DP-3)
Industry guidelines promote a systematic approach: assess risks, choose the most suitable transfer method, define clear procedures and continuously improve based on experience. Documents from IMCA, G+, IOGP and others outline roles and responsibilities, communication protocols, equipment standards, maintenance regimes and emergency plans. They stress that no method is inherently “safe” or “unsafe”; suitability depends on context such as distance, metocean conditions, installation layout and workforce profile. Regular toolbox talks, permit-to-work systems and post-transfer reviews are encouraged, alongside reporting and investigation of near misses. The overarching goal is to keep risk ALARP by combining technical controls, competent personnel and organisational learning across helicopter, vessel, gangway, ladder and basket operations. Reference: IMCA – Guidance on the Transfer of Personnel to and from Offshore Vessels and Structures
Emergency evacuation and medical evacuation (medevac) are integral to offshore transport strategies. Helicopters are usually the primary medevac asset, capable of rapidly reaching installations and transporting casualties to onshore hospitals or dedicated medical facilities. Emergency response plans define dedicated SAR aircraft, winch procedures and rendezvous points with rescue vessels. Marine assets such as fast rescue craft, standby vessels or ERRVs provide immediate on-scene support, recovery from the water and initial treatment. Regulations and guidelines require regular drills, coordination with coastal rescue agencies and availability of trained medical personnel offshore. Lessons from past incidents continually refine flight duty rules, survival equipment standards and communications protocols to reduce response times and improve patient outcomes. Reference: Offshore Norge – Recommended Guidelines for Offshore Helicopter Operations
On remote FPSOs and platforms, crew changes are meticulously choreographed events. Most personnel arrive and depart by helicopter on fixed changeover days, with check-in, manifesting, baggage control and safety briefings handled at an onshore heliport. On board, handover is planned shift by shift, ensuring continuity of critical roles such as control room operators and marine crew. Where helideck capacity or weather is limited, operators may spread crew change over several flights or days. Some FPSOs use supply vessels or W2W ships for supplementary personnel, especially project teams, with transfer windows aligned to cargo operations. Logistics teams coordinate with marine and aviation departments, factoring in bunkering, waste backload and regulatory requirements on maximum offshore tour length and rest periods.
Reference: Offshore Norge – Recommended Guidelines for Offshore Helicopter Operations
Several trends are reshaping how people reach offshore workplaces. In marine transfers, motion-compensated gangways, improved hull forms and hybrid propulsion systems are extending safe operating windows while cutting emissions. In aviation, newer helicopters, stricter design standards and advanced planning tools aim to improve safety and efficiency. For offshore wind and emerging energy hubs, dedicated Service Operation Vessels with W2W systems are becoming floating hotels and logistics bases, reducing helicopter dependency. Digital solutions such as real-time tracking, electronic mustering and condition-based maintenance for transfer equipment support better decision-making and emergency response. Looking ahead, operators are also exploring drones for small cargo and remote inspections, which may indirectly improve personnel safety by reducing the need for some human transfers. Reference: Clarksons – Essential Vessels for Offshore Windfarm Construction and Operations
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A walk-to-work gangway is a bridge system installed on a vessel that allows technicians to step directly between the ship and an offshore wind turbine or substation. Modern W2W systems are usually motion-compensated, meaning hydraulic or electric actuators counteract vessel movement in heave, roll and pitch so that the gangway tip remains relatively still at the landing point. This enables safe personnel transfer in higher sea states compared with traditional step transfers from small crew transfer vessels. In offshore wind, W2W gangways are typically mounted on Service Operation Vessels (SOVs), which act as floating bases providing accommodation, workshops and spare parts close to the wind farm. Reference: https://www.dnv.us/article/a-safer-walk-to-work-86093/
Offshore wind uses several gangway types, but the most common are motion-compensated telescopic gangways mounted on SOVs. These can extend and retract to reach turbine landings at different distances and heights, while active motion compensation keeps the walkway stable. Some systems integrate cargo trolleys or lifts to move tools and small components alongside personnel. Passive or semi-active gangways, relying on mechanical systems rather than full active control, are used in less demanding environments or retrofits. Integrated “access and cargo towers” combine gangway, elevator and tower structures in one package. Across designs, key features include adjustable-height interfaces, non-slip walk surfaces, handrails, and integrated fall-protection attachment points to support safe turbine access in a variety of sea and wind conditions. Reference: https://www.dnv.com/news/2015/bridging-the-gap-dnv-gl-launches-first-standard-for-classification-of-offshore-gangways-49236/
Motion-compensated gangways use sensors, control systems and actuators to counteract vessel motions so that the gangway tip follows a fixed point on the offshore structure. Gyros, accelerometers and position reference systems measure vessel movement, while real-time control algorithms drive hydraulic or electric cylinders in a pedestal, boom or parallel linkage. These adjust the gangway’s angle and length to maintain a constant position and orientation at the landing, effectively “filtering out” wave-induced motions. Advanced systems use model-based control and time-domain simulations to predict and compensate motion more accurately, widening the operable wave-height envelope. The result is a landing that feels almost static to technicians, even as the vessel continues to move beneath them in the sea. Reference: https://www.dnv.com/expert-story/maritime-impact/Dynamic-simulations-widen-window-for-walk-to-work-operations/
The core technical standard for offshore personnel transfer by gangway is DNVGL-ST-0358, which sets requirements for structural integrity, motion-compensation performance, control systems and safety functions. Manufacturers and owners often use it to demonstrate that their gangways meet industry-accepted criteria. In parallel, IMCA’s Guidelines for Walk to Work Operations (M254) provide practical recommendations for planning, executing and managing W2W operations, including vessel selection, competence, maintenance and emergency preparedness. For offshore wind specifically, G+ and the Energy Institute publish good-practice guidelines on offshore wind farm transfer, integrating W2W into a wider transfer toolbox. Together, these documents help operators and vessel owners align on a consistent risk-based approach to using gangways in turbine maintenance campaigns. Reference: https://www.dnv.com/news/2015/bridging-the-gap-dnv-gl-launches-first-standard-for-classification-of-offshore-gangways-49236/
On SOVs, the gangway is a central feature of the ship’s overall logistics concept. It is usually mounted along the vessel centreline or slightly offset, on an elevated tower with integrated lift and stair access from accommodation and workshops. This positioning maximises workability by providing the largest possible operating envelope across headings and sea states. The SOV’s hull form, dynamic positioning (DP) system, propulsion and thrusters are designed to support stable gangway operations, often to specific significant wave-height targets. Internally, flows of technicians, tools and spare parts are organised around the gangway tower, with staging areas, locker rooms and storage nearby. As a result, the SOV becomes a floating hotel and warehouse from which technicians can make daily W2W trips to turbines and substations. Reference: https://www.damen.com/vessels/offshore/service-operation-vessels/sov-9020
Operational envelopes describe the combinations of wave height, wind speed, current and vessel heading in which a gangway can safely be used. For modern SOV-mounted W2W systems, this might mean transfers up to a significant wave height of around 2.5–3.0 metres, depending on design, turbine layout and risk appetite. The envelope is determined through engineering analysis, model tests and sometimes time-domain simulations, taking account of vessel motions, DP performance and gangway capabilities. Operators then translate these envelopes into practical go/no-go criteria and decision trees in marine operating manuals. Real-time monitoring of environmental conditions, vessel motions and gangway loads helps masters and transfer supervisors ensure operations remain inside the certified envelope, with clear procedures for suspending transfers if limits are approached. Reference: https://www.dnv.com/expert-story/maritime-impact/Dynamic-simulations-widen-window-for-walk-to-work-operations/
Traditional crew transfer vessels (CTVs) perform “step transfers,” where the bow pushes onto a turbine boat landing while technicians step across. This is simple and proven, but can be physically demanding and limited by wave height, especially as wind farms move further offshore. W2W from an SOV offers a different model: technicians sleep on board close to the field and walk across a motion-compensated gangway each morning. This can extend the workable weather window, reduce travel fatigue and enable higher turbine availability in far-from-shore projects. However, SOVs with gangways are more capital-intensive and typically support larger projects or long-term service campaigns. At the same time, CTVs remain attractive for nearshore or smaller wind farms where simple day-trip access is sufficient. Reference: https://www.gplusoffshorewind.com/technical-library/good-practice-guideline-offshore-wind-farm-transfer
W2W gangways build safety into both design and operation. Technically, they provide a continuous, hand-railed walkway with non-slip surfaces and often integrated fall-arrest anchor points, reducing the need for exposed step transfers. Motion-compensation systems limit relative movement at the landing, reducing the risk of trips or impacts. Many gangways include automated safety interlocks, emergency stop functions, load monitoring and alarms to prevent overload or misuse. Operationally, good-practice guidance emphasises toolbox talks, clear communication between bridge and gangway operators, defined escape routes and emergency recovery procedures. Combined with appropriate PPE and training, these features reduce the likelihood and severity of incidents when accessing turbines in challenging offshore environments compared to more manual transfer methods. Reference: https://www.energyinst.org/technical/publications/sectors/renewables/good-practice-guideline-offshore-wind-farm-transfer
Daily W2W planning begins with weather and sea-state forecasts, combined with DP capability, gangway envelope and turbine work scopes. Marine coordinators, SOV officers and wind farm control rooms agree which turbines to visit, in what sequence, and during which transfer windows. Before starting, a toolbox talk reviews conditions, vessel approach strategy, gangway settings, PPE and communication protocols. During operations, the bridge, DP operator, and gangway operator maintain continuous contact, adjusting heading or thrust as needed. Decision-support tools from IMCA and others help assess whether conditions remain within limits, and formal stop-work authority is given to key personnel. Lessons from near misses or minor incidents feed back into procedures, gradually refining how W2W is used in that specific project. Reference: https://www.imca-int.com/news-events/imca-news/news/imca-publishes-revised-guidance-on-walk-to-work-operations/
Despite their benefits, motion-compensated gangways introduce specific risks. Potential failure modes include loss of vessel position, unexpected gangway motion due to control system faults, overload or collision with the turbine landing. There is also risk during “landing” when operators work at the leading edge to secure or release the connection. Recent safety alerts have highlighted concerns about pinch points, crush zones and the consequences of uncontrolled movement if interlocks fail. Mitigations include redundancy in motion-control systems, regular inspections, defined exclusion zones, comprehensive training for gangway operators and strict adherence to operating envelopes. Regulators and safety agencies continue to review incident data to refine guidance, underlining that W2W must be managed as a high-hazard but controllable activity. Reference: https://www.dnv.us/article/a-safer-walk-to-work-86093/
Many offshore wind gangways are designed not just for people but also for light cargo. Telescopic bridges may integrate trolleys or tracks for moving tool cases and small components, while some systems include lifts or cranes adjacent to the gangway tower for heavier loads. This enables technicians to bring essential equipment directly to the turbine in one movement, rather than relying on separate crane lifts or CTV deliveries. Design standards like DNVGL-ST-0358 distinguish between personnel and combined personnel-and-cargo modes, with different load factors and operational constraints. In practice, operators set limits on trolley weight, securing methods and traffic management, ensuring that cargo handling does not compromise egress routes or create trip hazards on the gangway walkway. Reference: https://www.dnv.com/news/2015/bridging-the-gap-dnv-gl-launches-first-standard-for-classification-of-offshore-gangways-49236/
Using a gangway often brings technicians directly onto turbine platforms or landings, where working at height begins immediately. G+ guidance on working at height in offshore wind emphasises pre-planned safe systems of work, including anchor points for personal fall-protection equipment located near gangway interfaces. Design requirements cover guardrail heights, gate arrangements and the avoidance of unprotected edges where people egress from the gangway. Rope-access systems, ladders and service lifts used beyond the landing are managed under separate procedures, but they must integrate with W2W access so that technicians can transition safely between systems. Rescue planning is critical, ensuring that anyone who falls or becomes incapacitated can be quickly retrieved from areas around the gangway landing and turbine access points. Reference: https://www.gplusoffshorewind.com/technical-library/good-practice-guideline-working-at-height-in-the-offshore-wind-industry
Digitalisation is increasingly embedded in gangway systems and SOV operations. Motion-compensation controls already rely on advanced algorithms and sensor fusion, and many systems log detailed operational data on loads, usage cycles and environmental conditions. This supports condition-based maintenance and post-incident analysis. Simulation tools help design and verify operational envelopes and can be used for training bridge and gangway operators in virtual environments. Some projects are exploring autonomous landing functions that allow the gangway to automatically position and connect to the turbine, reducing operator workload and standardising approach profiles. Fleet-wide data sharing among operators, class societies, and OEMs may, over time, lead to better performance benchmarking and the refinement of guidelines for specific hull-gangway-site combinations. Reference: https://cdpstudio.com/use-cases/uptime-international/
As offshore wind expands into new regions such as the US, Asia and deeper European waters, W2W solutions are being adapted to local conditions, regulations and vessel fleets. In China, for example, the first SOVs with motion-compensated gangways are now entering service to support large wind clusters, bringing proven North Sea concepts into different metocean regimes. In the US, industry guidance such as the American Clean Power Association’s Offshore Marine Transfer Guidance references W2W gangways alongside other transfer methods, framing them within US regulatory structures. Local shipyards and designers are developing region-specific SOV designs that integrate gangways, daughter craft and cranes while meeting national crewing, cabotage and environmental requirements. This localisation is helping standardise safer turbine access as global offshore wind scales up. Reference: https://cleanpower.org/resources/offshore-marine-transfer-guidance/
Future W2W developments focus on further widening the operating window, reducing emissions and increasing automation. Research continues into lighter materials, improved motion-control algorithms and integrated energy-efficient power systems, particularly as SOVs move toward hybrid or fully electric propulsion. Autonomous or semi-autonomous gangways with advanced landing systems aim to standardise approaches and reduce human error during connection. Combined access solutions, such as gangways integrated with elevators, cargo systems and even drone launch pads, may streamline turbine logistics. Digital twins and real-time simulation could allow operators to “test” planned transfers virtually before executing them. As offshore wind moves into harsher environments and floating wind, gangways will also need to handle relative motion between two floating units, driving further innovation in mechanical and control design. Reference: https://www.ampelmann.nl/knowledge-hub/walk-to-work-the-new-standard-for-safe-and-efficient-offshore-access
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A standard crew transfer follows a series of repeatable milestones: pre-planning and risk assessment, departure from port or SOV, transit to the field, vessel approach to the structure, station-keeping, connection or landing of the transfer system, personnel movement, confirmation that the transfer is complete, and finally demobilisation and reporting. Each phase has its own hazards and decision points, so good practice guidelines treat transfer as an end-to-end process rather than just the moment of stepping across. Offshore wind guidance from G+ and the Energy Institute explicitly maps these phases and links them to controls such as toolbox talks, checklists, environmental limits and clear stop-work authority for key roles. Reference: https://www.energyinst.org/technical/publications/sectors/renewables/good-practice-guideline-offshore-wind-farm-transfer
Pre-transfer risk assessment is where most of the risk is managed, long before anyone steps onto a gangway. Teams review weather forecasts, DP capability, turbine layout, gangway operating envelopes, passenger profiles and any concurrent operations such as lifting. Good practice guidance recommends structured tools like task risk assessments, dynamic risk assessments and bow-tie diagrams to identify credible failure modes and assign controls. Topics typically include man-overboard scenarios, loss of position, communications failures, medical issues and escape routes. IMCA’s W2W guidance and G+ transfer guidelines both emphasise that this assessment should be revisited immediately before operations via toolbox talks, so that real-time information and lessons learned are integrated rather than relying solely on generic, one-off studies. Reference: https://www.imca-int.com/resources/technical-library/document/8bc53e5f-c55b-ee11-8def-6045bdd0ef2e/
Weather and sea state directly shape the risk profile of crew transfers. High waves and swell increase vessel motions, which can exceed gangway envelopes and make CTV bow landings unsafe. Strong winds affect both vessel handling and technician stability on exposed platforms, while currents can reduce DP capability margins. Poor visibility and precipitation complicate navigation, lookout duties and visual communication at the landing interface. Guidance from G+ and DNV stresses the need to define clear environmental limits and to use real-time data, including wave buoys and motion sensors, rather than relying solely on forecast conditions. Dynamic simulations are increasingly used to understand how specific hull and gangway combinations respond in local metocean conditions, helping operators set realistic go/no-go criteria and avoid marginal decisions. Reference: https://www.dnv.com/expert-story/maritime-impact/Dynamic-simulations-widen-window-for-walk-to-work-operations/
During approach, the master must bring the vessel into a safe position relative to the structure while avoiding contact with turbine foundations, boat landings or subsea assets. Hazards include misjudged closing speeds, unexpected gusts, swell interactions and traffic from other vessels. Once on station, dynamic positioning or manual control must maintain heading and distance within tight tolerances so the gangway can connect and remain within motion limits. A loss of position can lead to sudden gangway overloads or hull contact. DNV’s work on DP capability standards shows how capability plots, redundancy concepts and verification tests are used to quantify safe operating envelopes. In practice, clear approach procedures, well-rehearsed abort plans and strong bridge–gangway communication are essential mitigations.
The landing interface is where the vessel, gangway and structure all meet, so minor errors can have significant consequences. IMCA identifies hazards such as crush and pinch points between the gangway and the landing, unexpected gangway movement during connection or disconnection, and overloading due to excessive forces from vessel motions. There is also a risk of personnel being struck by moving equipment, tripping over thresholds, or being present in exclusion zones during landing. To control these hazards, guidance calls for engineered safety functions, including interlocks, alarms and automatic retraction modes, combined with procedural controls like step-by-step landing checklists, clear hand signals or radios, and restricted access to the work area. Properly designed landing gates, guards and markings on the structure further reduce exposure. Reference: https://www.offshore-mag.com/vessels/article/14187714/international-marine-contractors-association-issues-offshore-walk-to-work-guidance
Slips, trips and falls are among the most common incident types in offshore wind, and crew transfer is a high-risk context. Typical causes include wet or oily deck surfaces, cluttered walkways, poorly stowed tools and abrupt vessel motions that upset balance. Transitions between different surface levels, such as stepping onto the gangway or turbine platform, create additional trip hazards if thresholds, gratings or cable routes are poorly designed. G+ analysis of incident data shows that seemingly minor housekeeping issues can escalate when combined with fatigue, time pressure or poor lighting. Guidance, therefore, stresses non-slip surfaces, good drainage, strict housekeeping standards, adequate lighting, and the use of handrails and three-point contact wherever possible, backed by campaigns to reinforce good habits among technicians and vessel crews. Reference: https://www.energyinst.org/technical/publications/topics/offshore-safety/good-practice-guideline-working-at-height-in-the-offshore-wind-industry
Once technicians step off a CTV or gangway onto a turbine, they are often immediately exposed to working-at-height risks at landings, ladders and platforms. Unprotected edges, open hatches, and transitions to ladder systems can lead to falls if guardrails, gates and anchor points are not correctly designed and used. The G+ / Energy Institute working-at-height guideline highlights that rescue planning must start at these interfaces, ensuring that if a technician falls onto fall-arrest equipment, there is a realistic way to retrieve them promptly. It also stresses compatibility between turbine anchor points, lanyards and PPE brought from the vessel. Clear demarcation between safe and unsafe areas, along with disciplined use of twin-lanyard systems, helps manage risk during the critical minutes after disembarkation. Reference: https://www.gplusoffshorewind.com/technical-library/good-practice-guideline-working-at-height-in-the-offshore-wind-industry
Human factors are often the hidden root cause behind technical or procedural failures. Fatigue from long shifts, rough transits or repeated transfers can reduce situational awareness, slow reactions, and erode adherence to procedures. Cognitive overload on the bridge, DP desk or in marine coordination centres can lead to missed cues or incorrect decisions about weather windows and vessel headings. Miscommunication between the vessel crew, gangway operator, and turbine technicians can cause premature moves, unsafe step-offs, or confusion during emergencies. HSE analyses in offshore wind underline the value of designing operations around human limitations: limiting shift length, managing workload, using standardised phraseology, closed-loop communication, and ensuring that anyone can call “stop” without fear of blame when something does not look or feel right. Reference: https://www.barrington-energy.com/news/exploring-the-implementation-of-health-and-safety-standards-in-offshore-wind-farms/
Emergency planning for crew transfer typically covers scenarios such as man overboard, medical emergency on board or on the turbine, loss of vessel position, gangway or ladder failure, fire, and collision or allision with structures. IMCA’s W2W guidance describes how emergency preparedness should be integrated into procedures, including defined roles, communication flows, drills and links to incident reporting schemes. G+ transfer guidance likewise requires that operators be able to demonstrate effective rescue capabilities for technicians at the landing, in the tower and in the water. Plans must interface with national search and rescue organisations and consider realistic response times. Regular exercises involving marine coordination, SOV crews, and wind farm control are vital to ensure paper plans translate into effective action offshore. Reference: https://balticwind.eu/mca-finalises-guidelines-for-walk-to-work-w2w-operations/
Man-overboard (MOB) is one of the most serious hazards during crew transfer, particularly when technicians are moving on open decks or near boat landings. Controls begin with design: safe rail heights, good lighting, non-slip surfaces, and minimising the need to work at the deck edge. Procedurally, lifejackets or immersion suits are mandatory, and technicians are briefed on safe movement and muster points. Vessels are equipped with recovery gear such as ladders, scrambling nets, Jason’s cradles or rescue boats, and crews practise MOB drills regularly. Guidelines on small service vessels and offshore wind transfer encourage clear MOB procedures that consider turbine structures, currents and visibility, and emphasise swift alerting of marine coordination and national SAR resources to avoid delays in locating and recovering a casualty. Reference: https://www.offshore-energy.biz/g9-releases-ow-good-practice-guidelines/
Competence requirements cover multiple roles: vessel masters, DP operators, gangway operators, marine coordinators and turbine technicians. IMCA and G+ guidance both highlight the need for formal qualifications for bridge and DP staff, OEM-specific training for motion-compensated gangways, and task-specific training for technicians on transfer procedures, PPE use and emergency actions. Working-at-height, sea-survival and first-aid courses are typically mandatory. Competence is not just about certificates; it also involves supervised experience, assessments and periodic refreshers. Good practice documents recommend clear competence matrices that align roles with minimum training and experience levels, along with systems for recording and verifying this before allowing people to participate in transfers. Incident learnings are fed back into training content to address new or emerging risks in offshore wind projects. Reference: https://www.imca-int.com/news-events/commentary/raising-standards-for-walk-to-work/
Marine coordination centres and wind farm control rooms sit at the heart of safe crew transfer logistics. They manage turbine status, isolation permits, vessel movements, weather updates and emergency response. G+ transfer guidelines set expectations for how these functions interact, recommending clear responsibility matrices, standard communication protocols and shared situational awareness tools such as live vessel-tracking and turbine access boards. Before transfers, coordinators confirm that turbines are available, no conflicting work is underway, and environmental limits are respected. During operations, they maintain radio contact, log key events and are the first point of escalation in case of incidents. Afterwards, they collect reports and near-miss data. Good practice emphasises that this interface must be tested regularly through drills and joint training, not just documented verbally. Reference: https://www.gplusoffshorewind.com/whats-new/g-offshore-wind-farm-transfer-good-practice-guideline
Different transfer methods have distinct risk characteristics. CTV bow step transfers are simple but limited by wave height and rely heavily on technician agility, making them more challenging as farms move farther offshore. Motion-compensated W2W gangways reduce physical demands and widen the weather window, but introduce complex mechanical and control systems and new interface hazards. Crane and personnel basket transfers can be useful in some oil and gas contexts but are generally discouraged in offshore wind except where specifically engineered and justified, due to exposure to swinging loads and dependence on crane operation. G+ transfer guidance and IMCA’s W2W document both stress that operators should select the method with the lowest overall risk for their specific site and operation, not default to tradition or cost. Reference: https://www.gplusoffshorewind.com/__data/assets/pdf_file/0008/763523/Good-practice-guideline-Offshore-wind-farm-transfer.pdf
Incident data collated by G9/G+ has driven many improvements in transfer practice. The early years of offshore wind highlighted frequent minor injuries from slips, trips, manual handling, and working at height during access. Analysis of these trends led to targeted good-practice guidelines on small service vessels and working at height, along with improved vessel designs, access arrangements, and training. Data sharing has also revealed the importance of robust reporting cultures and learning from near misses rather than waiting for serious harm. As projects move into harsher environments, ongoing monitoring of W2W and SOV operations is informing updates to guidance, including IMCA’s revised M254, ensuring that industry practices evolve alongside changing technology and project geographies. Reference: https://www.4coffshore.com/news/g9-delivers-working-at-height-guide-nid1099.html
Digital tools are increasingly used to understand and reduce crew transfer risks. Time-domain simulations of coupled vessel–gangway–structure dynamics help predict motion responses in site-specific wave climates, allowing operators to choose appropriate vessels, refine gangway settings and set realistic weather limits. Research on digital twins for SOVs explores how real-time data from DP systems, motion sensors and weather feeds can be integrated to forecast workability and support go/no-go decisions. Logging of gangway usage, loads and alarms enables condition-based maintenance and early detection of emerging issues. Over time, aggregated data from many transfers, combined with incident reports, may enable more predictive approaches to safety, identifying patterns that humans alone might miss and supporting continuous improvement in offshore personnel transfer operations. Reference: https://www.dnv.com/maritime/vessel-types/offshore-service-vessels/
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Crew Companion by Identec Solutions
Industry: Offshore Oil & Gas | Wind Energy | Ship building | Offshore Logistics | Jobs & Roles |
Production Process: Exploration | Construction | Production | Decommissioning | Transport | Refining | Walk-to-Work |
Offshore Installations: FPSO | FLNG | Platforms | SOVs | CTVs | Sub-sea infrastructure | Tankers |
Safety: Access Control | POB | Workplace Safety | Workplace Health | Emergency | Training | Mustering | Regulations | Risk Assessment | Safety Assistance Technology |
Activity: Oil | Gas | Wind | Deep Sea Mining |
Areas: North Sea | Middle East | South Atlantic | Indian Ocean | Pacific Ocean |