When chartering offshore vessels for operations in icy or extremely low temperatures, both vessel owners and charterers must recognize several key factors that influence operational safety and efficiency. These considerations include the characteristics of the ice regime, the season of operations, the vessel's ice capability, and the crew's experience. An Ice Navigator, who is a qualified crew member or a supernumerary, plays a vital role in ensuring safe navigation in these challenging conditions.
To mitigate risks associated with breaches of International Navigating Limits, it is advisable to maintain or arrange for appropriate insurance coverage. Understanding the significance and limitations of ice class notation is crucial. While an ice class designation indicates a vessel's capability to operate under specific cold environmental conditions, it does not guarantee suitability for commercial operations in extreme climates. Ice classification focuses primarily on a vessel's structural integrity, propulsion power, and overall arrangements. A vessel with an ice classification is designed to maintain a minimum speed and power output in icy conditions, ensuring hull integrity for independent navigation or under icebreaker escort. However, operations beyond the defined classification limits necessitate additional assessments, such as calculating ice numerals in accordance as an example with the Canadian Ice Regime System or adhering to recommendations outlined in Ice Certificates. Furthermore, optional winterization class notation reflects the vessel's preparedness for acceptable performance in extreme cold.
Owners and charterers must ensure that vessels slated for harsh environmental operations are adequately prepared and equipped. Key aspects to consider include:
Providing suitable and robust equipment.
Implementing protective measures for equipment.
Establishing procedures for safe operational practices.
Prioritizing personnel welfare.
Operators are encouraged to create a comprehensive checklist addressing the unique requirements of operations in low temperatures associated with ice navigation and escort operations. It is also prudent to refer to the IMO Assembly Resolution A26.Res.1024, which offers guidelines for ships operating in polar waters.
Classification
The Ice Class Notation is a critical factor for offshore vessels operating in the Arctic. Most classification societies provide guidelines for selecting the appropriate ice class based on regional conditions, seasonal variations, and operational modes, whether independent or escorted. Each vessel's ice class establishes an upper ice water line (UIWL) and a lower ice water line (LIWL), dictating the allowable draught while operating in ice.
Vessels must verify the validity of hull and machinery insurance specific to the intended operating area. This coverage is essential for safeguarding against potential operational risks in icy environments.
The experience of the crew is paramount for safe navigation in ice. Key considerations for crewing include:
Ensuring the Master and navigating officers possess relevant experience in ice navigation and operating in extreme cold.
Providing basic ice navigation training for all navigating officers.
Determining the necessity for an Ice Navigator during ice transit and obtaining evidence of their training and experience.
Training the crew in damage control procedures and minor hull repairs.
Equipping the crew with cold weather survival techniques.
Assessing manning levels, factoring in the potential need for additional deck crew due to shorter shift patterns in adverse conditions.
Recognizing the implications and limitations of ice class notation is vital for operational success in such challenging environments.
Additionally, it is critical to implement a fatigue management plan that addresses the physical and mental demands of operating in icy conditions, which may necessitate doubling up watches to ensure crew effectiveness and safety.
The safe operation of vessels navigating through ice regimes across various seasonal changes demands a higher level of skill and technical proficiency than is typically required during standard operating conditions. To address this need, it is essential to provide crew members with appropriate training that enhances their existing experience. This training is vital for ensuring that the crew is adequately prepared for the unique challenges posed by icy waters.
For vessels operating in the Arctic, the International Maritime Organization (IMO) recommends, as outlined in A26.Res.1024 Guidelines for Ships Operating in Polar Waters, that at least one qualified Ice Navigator be onboard. Additionally, local regulations may enforce this requirement. The Ice Navigator can be either a qualified member of the vessel’s crew or a supernumerary. If only one certified Ice Navigator is present, it is advisable that this individual hold the position of either the Master or Chief Officer.
The IMO defines an Ice Navigator as an individual who, besides being qualified under the Standards of Training, Certification and Watchkeeping (STCW) Convention, possesses specialized training and qualifications to guide a vessel through ice-covered waters. To qualify as an Ice Navigator, an individual should provide documentary evidence of completing relevant on-the-job training and may also include experience with simulation training. Furthermore, it is recommended that Ice Navigators complete an approved training program in ice navigation, with suitable documentation confirming their successful completion.
It is important that the Master, officers responsible for navigational watches, and those overseeing engineering watches have substantial experience and training concerning operations in ice and severe sub-zero temperatures. In addition, all officers and crew members should receive adequate training for the various scenarios they may encounter while operating in low temperatures, engaging in ice navigation, and participating in icebreaker escorts. Training formats may include in-service training, simulator training and other with a focus on cold weather survival techniques.
The senior officers on the vessel should ideally possess a minimum of 30 days of experience operating in ice or severe sub-zero temperatures. When assessing the experience and training of officers, it is preferable for this experience to be accrued in the rank they currently hold onboard, though it is acknowledged that this may not always be feasible.
The helmsman plays a crucial role in navigating through icy conditions, and it is important to consider providing simulator training or utilizing experienced ice helmsmen to enhance navigational safety. As an example, according to the Canadian Arctic Shipping Pollution Prevention Regulations, Ice Navigators are required to have served on a ship as a Master or as the person in charge of a deck watch for at least 50 days. Of these days, a minimum of 30 must be spent in Arctic waters where the vessel required assistance from an icebreaker or needed to perform maneuvers to avoid ice concentrations.
An Ice Advisor, typically provided by a local Port Authority, is tasked with ensuring safe ice navigation under particular conditions relevant to the local port approaches. This distinction emphasizes the importance of tailored training and expertise in ensuring safe operations in ice-affected waters.
When operating vessels in icy conditions, it's essential to have well-defined procedures and precautions. These protocols ensure safety and efficiency, particularly in harsh environments like the Arctic and Sub-Arctic regions. Here are the critical elements that operators should implement:
Management of Vessel Draught
Operators must manage the vessel’s draught to ensure that vital components—such as sea suction inlets, propellers, thrusters, and moon pools—remain submerged beneath the ice level. This is crucial for maintaining functionality and preventing ice-related damage.
Operating and Training Manuals
It is imperative to have operating and training manuals tailored for ice and extreme cold conditions. These manuals should consider the distance to available Search and Rescue (SAR) facilities to prepare crews adequately for emergencies.
Risk Assessment
A thorough assessment of ice navigation and the risks associated with cold weather operations is vital. Operators should continuously evaluate these risks to adjust protocols as needed.
Ice Navigation and Escort Operations
Conducting ice navigation and icebreaker escort navigation requires specialized knowledge and training. Crews must be adept at operating in these challenging conditions to ensure safety.
Receipt of Ice Navigation Information
Receiving accurate ice navigation information, such as ice charts and satellite imagery, is essential for planning and executing safe operations.
Cold Weather Operations
Operators must ensure that accommodation spaces, emergency exits, fire-fighting systems, lifesaving appliances, and critical equipment are protected against cold weather. Access to these areas must be maintained.
Slip and Fall Prevention
To prevent slips and falls on open decks, walkways, and ladders, operators should implement suitable measures. These may include trace heating, sand application, or non-slip coatings.
Freezing Prevention of Services
Preventing the freezing of services on exposed decks—such as fire lines, air systems, control systems, and instrumentation—is crucial. Minimizing or eliminating dead legs in these systems can further reduce the risk of freezing.
Bulk Cargo and Ballast Systems
It is also necessary to prevent the freezing of bulk cargo and ballast systems, including ballast water and venting systems, to ensure operational integrity.
Dangerous Ice Accretion
Operators must have strategies in place to prevent dangerous ice accumulation on the vessel.
Stability Calculations
Stability calculations should consider the effects of ice accretion, including the freezing of entrapped water. This ensures the vessel maintains its stability in icy conditions.
Provision of Cold Weather Clothing and PPE
Adequate cold weather clothing and personal protective equipment (PPE) should be provided to crew members. This may include spiked boots or strap-on spikes for safe movement on deck.
Ice Removal Tools and Materials
Operators should supply suitable tools and materials for the prevention and removal of ice and snow on board. This includes covers, mallets, and shovels.
Ice Emergency Towing Procedures
Establishing clear ice emergency towing procedures is essential for rapid response in ice-related incidents.
Personnel Transfer Procedures
Operators must have procedures for safely transferring personnel in icy and sub-zero conditions.
Medivac Contingency Plans
Medivac contingency plans should be in place for emergencies in ice and severe cold.
Ice Management Plan
Developing an ice management plan for the operational area is vital to manage the risks associated with ice navigation effectively.
Wildlife Interaction Plan
Operators should have a plan in place for interacting with wildlife to prevent accidents and disturbances.
Actions in the Event of Being Beset
Finally, operators must establish clear actions to take if the vessel becomes beset by ice.
Navigation procedures must be adjusted for ice navigation, requiring more caution than typical open water navigation. Operators should consider the following:
Terrestrial Navigation Aids
Operators should understand the hazards associated with terrestrial navigation aids in polar waters, such as buoys being dragged off station or lighthouses becoming obscured.
Nautical Charts Limitations
There are inherent limitations in nautical charts and precautions that must be taken when navigating poorly-charted waters. Familiarity with the chart projections in use is essential.
Electronic Positioning Systems
Operators should recognize the limitations of electronic positioning systems at high latitudes, which can be less reliable.
Ice Interference with Depth Sounding
Ice can interfere with depth-sounding equipment, necessitating careful monitoring and adjustments during navigation.
Glare on Lookouts
The effect of glare on lookouts must be considered, as it can impair visibility.
High-Latitude Compass Errors
High-latitude compass errors are common, requiring adjustments to magnetic compasses to ensure accurate navigation.
Radar Target Discrimination
Operators should be adept at discriminating between radar targets and ice features, especially in cluttered environments.
Search and Rescue Limitations
It's crucial to understand the limitations of search and rescue capabilities in icy waters.
Quality of Metocean Data
The lack of good quality metocean data—such as tides and currents—can pose challenges. Operators must be prepared to navigate in such conditions.
The bridge equipment used in ice navigation should address the unique challenges presented by icy environments. Key considerations include:
Heated Wheelhouse Windows
Wheelhouse windows should be heated to prevent ice accumulation, and any installed window-washing systems should have water drained.
Ice Detection Equipment
Equipment to assist with ice detection, such as high-definition ice radars and infrared cameras, should be installed.
Radar Optimization
Radars should be strategically placed to optimize performance while minimizing issues related to snow clutter and identifying close-up ice features.
Escort Duty Considerations
If escort duties are anticipated, radars must be positioned to avoid blind sectors when looking astern.
Trace Heating for Radar Units
Radar scanner units should have trace heating to ensure functionality in cold temperatures.
Searchlight Availability
A sufficient number of searchlights should be readily available, positioned for effective operation in ice and snow, and preferably controlled remotely from the wheelhouse.
Enclosed Bridge Wings
Enclosed bridge wings are recommended for added protection and visibility.
Speed and Distance Devices
Two speed/distance devices that operate on different principles—showing speed over ground or through water—should be available for reliable navigation.
Satellite Compass Availability
In high-latitude navigation, a satellite compass or equivalent system is essential due to the unreliability of magnetic and conventional gyrocompasses in these areas.
Echo Sounding Devices
Two independent echo sounding devices should be available to display and record depth under the keel accurately.
Weather and Ice Information
Devices for receiving ice and weather information charts and imagery are critical for informed decision-making.
Global Navigation Satellite System
A global navigation satellite system (GLONASS and/or GPS) should be in place, considering performance limitations in high latitudes.
De-Icing Equipment
Consideration should be given to de-icing equipment for aerials and antennas on top of the wheelhouse, as rime ice can impact functionality.
The design of hull and propulsion systems must accommodate the challenges of operating in ice. Considerations include:
Engineering System Ratings
The design ratings for main and auxiliary engineering systems should be suitable for anticipated icy conditions.
Propulsion Design
Main propulsion systems should be designed to handle resultant loads and vibrations from ice interactions, operating efficiently even when the vessel is inclined due to ice interaction.
Directional Control System
All vessels must have a directional control system (steering) designed for effective operation in icy conditions.
Double Bottom Construction
A double bottom construction should extend the entire length and breadth of the vessel, from fore peak to aft peak bulkheads.
Pollution Prevention
Design measures must ensure that pollutants are not trapped against the hull in areas at risk of significant ice impact.
Onboard Repair Capability
Equipment essential for safe vessel operation should be capable of repair using onboard resources.
Damage Control Materials
Sufficient damage control materials must be available to facilitate temporary repairs for minor hull breaches.
Ice-Free Sea Chests
Systems should be established to keep sea chests free of ice accumulation.
Suitable Hull Steel
Hull steel must be of a grade appropriate for exposure to low temperatures anticipated during operations.
Submerged Propeller
The propeller should be maintained at a depth sufficient to avoid ice interference, designed to withstand ice conditions.
Material Considerations
Propellers should be constructed from steel or equivalent materials, avoiding ordinary bronze due to the risk of damage.
Anchor Housing Design
The design of the anchor housing should protect the anchor from dislodgment and prevent damage from ice impacts.
Heating Systems for Accommodation
Accommodation heating systems must be adequate to sustain life during emergencies or extended entrapments, with emergency generators supplying power if necessary.
Air Intake Systems
Systems should prevent freezing or snow blockage of essential air intakes and venting systems, including those for cargo and ballast.
Cargo Tank Heating
If applicable, cargo tanks should feature means to prevent freezing, such as heating coils. Ballast and freshwater tanks may require heating or air bubbling systems.
Electrical Installation Standards
Electrical installations must be designed for reliable operation in anticipated cold conditions.
Fuel and Lubricant Reserves
Reserve supplies of fuel and lubricants should be carried, considering increased consumption due to operating in heavy ice.
Hull Protrusions
Attention should be given to hull protrusions, such as bilge keels and echo sounder transducers, to ensure they do not impede operations.
The lifesaving and emergency equipment must be winterized, with additional provisions as necessary. These may include:
All deck equipment is covered
All Deck Equipment is Covered to Prevent Ice and Damage
Lifeboat Specifications
If lifeboats are required, they should be of a totally enclosed design, equipped with engines that can start in sub-zero temperatures.
Lifeboat Heating
Lifeboats should have heating systems to ensure crew comfort during emergencies.
Fire Extinguishing Equipment
Equipment must be suitable for the temperatures expected during operations, and emergency fire systems should be accessible without obstructions.
Emergency Distress Signals
Vessels should carry emergency distress signals capable of functioning in low temperatures.
Radio Communications
Adequate radio communication systems must be in place for emergency communication, ensuring operability in cold conditions.
Survival Suit Inventory
A sufficient inventory of insulated survival suits should be available for the crew, accounting for all personnel onboard.
Ice Anchors and Related Equipment
Equipment must be available to facilitate ice anchoring if the vessel becomes beset, including ice anchors and associated gear.
In addition to operational procedures, equipment specifications, and safety measures, several other considerations are essential for successful operations in icy waters. These include:
Environmental Protection Protocols
Protocols should be established to protect the marine environment, particularly concerning sensitive wildlife habitats.
Communication with Relevant Authorities
Regular communication with relevant maritime authorities regarding ice conditions and regulations is crucial.
Crisis Management Training
Crew training should include crisis management scenarios specific to ice navigation, ensuring preparedness for emergencies.
Logistics for Provisions and Fuel
Logistics should be established for resupplying provisions and fuel, particularly when operating in remote locations.
Ideally, all deck equipment, especially winches, should be housed under cover to protect them from harsh environmental conditions. This is particularly important in the Arctic and Sub-Arctic regions, where operations may be conducted in ice and severe sub-zero temperatures. When equipment is exposed to the elements, it can be vulnerable to ice formation and other damage.
One of the significant risks associated with operating in icy conditions is the potential for wire to become dislodged from the sheave. This can lead to the wire becoming trapped between the sheave and cheek plate, which can compromise the equipment's functionality. Therefore, taking precautions to protect equipment from ice accumulation is crucial.
For any lifting operations, it is essential for the crane driver to maintain good visibility. This is especially critical if visual signals are used alongside verbal communication via radio. The windshield of the operator's cab should be adequately heated, either through blowers or heating elements, to ensure clear visibility. Additionally, pre-heating the cab and warming the hydraulic systems before operation can enhance safety. Safe access to and from the cab must also be ensured; thus, exposed ladders may not be suitable if they risk icing.
For vessels equipped with moon pools, it is preferable to position them within enclosed, heated areas. This design helps support personnel, umbilical tenderers, remotely operated vehicle (ROV) operators, and dive supervisors stay warm and alert during operations. Caution must be exercised regarding any water exiting the moon pool or being introduced with retrieved equipment, as this may freeze and create slip hazards.
Ice formation can also occur within the moon pool itself, especially during low-temperature conditions. Procedures should be established to manage and clear ice from the moon pool and other through-hull penetrations. Various methods can be employed, such as air bubbling systems, heating the water (for instance, by introducing engine cooling water), and utilizing pressurization to displace the ice.
When deploying equipment over the side of a vessel, the risk of ice contact must be taken into consideration. To mitigate this risk, deploying equipment through a moon pool is often recommended. This method provides a layer of protection for equipment during ice conditions.
The hull coating systems of offshore vessels can suffer significant abrasion damage in icy waters. In addition to wear on the coating, impact deformation of the hull plating is a real possibility. Vessel owners are encouraged to arrange for independent inspections of the hull both before and after ice voyages. There are specialized coatings available that offer significant resistance to ice abrasion, which may be beneficial for vessels operating in ice-covered waters for extended periods.
When operating in ice and severe sub-zero temperatures, specific considerations must be taken into account concerning the offshore support vessel's operations. The operational categories used for these considerations are based on the Offshore Vessel Inspection Database (OVID) by the Oil Companies International Marine Forum (OCIMF).
The safety of the crew working on deck is paramount. They should have access to warm areas to retreat to as necessary. An assessment of environmental conditions, including wind-chill exposure limits, should be performed, and shift routines should be adjusted to minimize exposure to harsh conditions.
Effective procedures should be established to maintain cargo deck areas free of ice and snow. Clear access to cargo securing points is crucial, and items such as drill pipes and casing should be equipped with end caps to prevent water ingress and subsequent freezing.
When operating in conjunction with offshore platforms, it is essential to be aware of the hazards posed by falling ice from the platform or from the cargo being lifted. Additionally, hoses used in bulk cargo operations can be vulnerable to damage from ice contact. These hoses should be kept under constant supervision, ideally raised above the ice using a crane. After transfer operations, hoses should be thoroughly drained to minimize the risk of freezing residues.
Evaluating the vessel's pumping performance when handling bulk cargoes such as brines, muds, and cement is necessary, particularly under low operating temperatures. For dry bulk cargo operations, driers fitted to compressors must be fully operational to ensure air has a low dew point, minimizing the risk of freezing.
Ice conditions can significantly impact the operational capabilities of stand-by vessels (SBVs) tasked with emergency response at offshore installations. For effective emergency response, SBVs must possess adequate maneuverability to navigate through various ice conditions that may be encountered.
When assessing response time requirements, it is crucial to consider the distance of the SBV from the offshore installation, especially in the presence of existing ice and icing conditions. Establishing realistic performance standards based on anticipated environmental conditions is vital, along with understanding the temporary refuge time of the installation.
To facilitate personnel evacuation during emergencies, clear rescue and recovery routes must be maintained through effective ice management practices. The transfer of personnel from the installation to the SBV can be complicated by rubble fields accumulating on the weather side, which can prevent the vessel from approaching closely.
In areas prone to large rubble fields and ridges, SBVs equipped with the capability to clear these fields should be utilized. This clearing can be performed by reversing through the rubble field, using propellers to flush and mill ice pieces away. Good operating practice dictates this should be done downdrift to prevent the vessel from drifting onto the platform in case of power loss.
The volume of ice cleared per hour is a common performance metric for rubble field clearing capability.
Ice drift poses a challenge during personnel evacuation from offshore installations. Drifting sea ice can impede the SBV's ability to maintain position, potentially leading to collisions with the installation. Therefore, routes and methods of approach to the installation in various ice conditions should be thoroughly discussed with the Offshore Installation Manager (OIM). The Master and crew should receive training to effectively perform evacuations under diverse ice conditions.
When recovering individuals from the water in open pack ice, the technique used resembles that employed in open water conditions. However, care must be taken to avoid damaging the rescue boats due to ice contact. Boats with glass reinforced plastic (GRP) hulls are generally not suitable for icy conditions because of their increased susceptibility to damage.
In close pack or compact ice conditions, using rescue boats to retrieve survivors from the water may be dangerous or impracticable. When this occurs, alternative rescue procedures, such as utilizing rescue baskets or nets, should be employed. The SBV Master must exercise caution when approaching individuals in the water surrounded by high concentrations of ice to avoid pushing ice towards them, which could lead to crush injuries.
When sea ice is thick enough (over 15 cm), it can support individuals weighing up to 100 kg. In such cases, it may be feasible to evacuate personnel directly onto the ice. Evacuees can then be transferred onto the SBV using the vessel's gangway or a personnel transfer basket. Before individuals step onto the ice, testing for adequate load-bearing capability should be conducted using an extended pole or a similar tool.
Operations involving anchor handling vessels often take place under challenging conditions. Due to their low freeboard, these vessels may have to conduct operations with the stern facing the weather, which can lead to icy decks. It is crucial for crew members to wear appropriate clothing and adjust work routines to include frequent breaks to prevent fatigue.
Identifying and managing risks to personnel on the working deck is essential. Measures to prevent slips and falls should be implemented, including wearing spiked shoes, gritting the decks, marking off ‘no-go’ areas, and utilizing safety harnesses. Automated anchor-handling systems can reduce the need for crew members to be on the working deck, thereby minimizing their exposure to harsh environmental conditions.
The freezing conditions can adversely affect anchor handling equipment, including rollers, pins, and mechanical stoppers. Arrangements should be made for de-icing these components. Additionally, using synthetic stretchers is discouraged as they can be damaged by ice and freezing water. Instead, a length of chain may be a more suitable alternative.
Towing operations in light ice conditions may proceed with standard tow line lengths. However, in pack ice situations, the tow lines must be shortened to enhance control of the vessel being towed. As ice concentrations increase or pressure rises, the tow line should be adjusted accordingly. In new ice without ice management, the tow line is deployed to allow the towed vessel to stay within the broken track.
In heavy pack ice, it is preferable to conduct tows with available ice management, deploying the tow line sufficiently to prevent it from becoming fouled by ice keels and sails. Specialist vessels designed for towing in ice are typically equipped with towing notches, dedicated winches, and bridle arrangements, which are crucial for safe operations.
Dynamic Positioning (DP) systems are critical for maintaining the position of offshore vessels in challenging environments, particularly in ice-covered waters and severe sub-zero temperatures. However, various limitations must be recognized when operating these systems under such conditions.
One of the primary concerns with DP operations in icy conditions is the impact of environmental factors on reference systems. The performance of both fan beam (laser-based) and radar-based systems (like Artemis) can be significantly affected by icing and fog. Ice accumulation can impede the operation of these scanners, leading to degraded signal accuracy.
Laser-based reference systems are particularly susceptible to false reflections from surface ice and can also be adversely affected by ice accretion on the equipment itself. To mitigate these challenges, it may be advantageous to use above-water systems, such as a Differential Global Positioning System (DGPS) station positioned on the installation. However, at high latitudes, signal strength can be compromised by ice accumulation on aerials.
Additionally, acoustic systems used in DP operations may encounter performance issues due to cold water thermoclines and the potential for false reflections originating from ice keels. The risk of damage to hull-mounted equipment, such as hydroacoustic transducers, is heightened when fast-moving ice comes into contact with the vessel.
When operating taut wire systems, it may be beneficial to deploy them through a moon pool rather than over the side of the vessel. Similarly, deploying acoustic systems through a moon pool could provide enhanced operational safety and performance.
Station-keeping during DP operations in ice requires careful consideration of several factors. Whenever feasible, the bow of the vessel should be oriented into the direction of ice drift, except when the installation offers substantial shelter from the drifting ice. A thorough assessment of ice conditions and the vessel’s station-keeping capabilities is essential to ensure safe operations.
It is important to allow for a larger station-keeping envelope in icy conditions to accommodate the unpredictable nature of ice movements. Effective ice management strategies will be necessary, potentially involving the assistance of icebreakers equipped with azimuth or podded propulsion systems. These strategies can help to minimize ice loads on the hull, reducing stress on the DP system.
The DP control system must be capable of adapting to rapidly changing ice forces. This adaptability may lead to increased utilization of thrusters and propellers, resulting in additional wear and maintenance demands on these components.
Moreover, the DP control system should construct an accurate representation of the environmental situation, taking into account the impacts of ice forces alongside traditional factors such as wind, waves, and current. It is crucial for DP operators to receive specialized training to understand the unique and often significant environmental loads exerted by ice. Understanding these loads and the system's capacity to manage them is essential for safe and effective operations.
In Arctic regions, stricter regulations are increasingly being imposed on the maximum allowable air emissions from operating vessels. Such restrictions may take the form of air permits that significantly limit operational capabilities. Vessel owners must explore a range of mitigation strategies when applying for these permits, including:
Implementing fuel-saving initiatives
Utilizing low-sulfur fuels
Switching from heavy fuel oil (HFO) to diesel
Employing selective catalytic reduction technologies
Considering alternative fuels, such as liquefied natural gas (LNG)
Air permits can be issued based on maximum continuous emissions or on a seasonal basis. To comply, accurate measurement systems must be installed onboard, and meticulous records must be maintained to demonstrate adherence to regulations. In some instances, vessels may be required to have a compliance officer on board to oversee emissions and ensure compliance with regulatory standards.
There are concerns regarding the effects of carbon black deposits from vessels on sea ice, as these deposits can potentially accelerate melting rates and increase the release of greenhouse gases in vulnerable areas.
To minimize emissions, positioning the stern of the support vessel against the installation can reduce the power required for station-keeping. This, in turn, can lead to lower emissions. However, careful consideration of prevailing weather conditions is essential, and both the vessel and the installation should be designed to accommodate this operational method effectively.
Given the relatively low freeboard of offshore vessels and their stationary nature, there exists a potential for interaction with local wildlife. Certain regulatory bodies require the presence of marine mammal observers onboard, which may include local indigenous personnel, to monitor wildlife concentrations and migrations, ensuring that vessels maintain a safe distance from marine life.
Vessels should have onboard plans outlining how to handle wildlife interactions should they occur. Information regarding the migration patterns of Arctic wildlife can be found on the Arctic Monitoring and Assessment Programme website.
Polar bears, as apex predators in the Arctic, are well-adapted to their frozen habitat and pose significant risks to humans due to their size and lack of natural predators. Their acute sense of smell is critical for locating prey, making it essential to manage food waste effectively to minimize scent exposure. Waste should be securely contained to prevent odors from attracting bears.
To ensure safety, protocols should be established for monitoring polar bear activity, including designated lookout responsibilities and refuge areas. In case of a bear sighting, an appropriate alarm system should be activated, and all access routes to accommodations should be secured. Caution is particularly important during low visibility conditions, such as at night or in inclement weather.
Seals are generally aware of incoming vessels and will often swim away before the vessel approaches. However, pollution from oil spills or discarded waste poses significant risks to seal populations. Discharges are regulated under The International Convention for the Prevention of Pollution from Ships (MARPOL), emphasizing the importance of responsible waste management.
During the long, dark winters in the Arctic, offshore vessels can provide a source of light, inadvertently attracting birds. This attraction poses a collision risk, particularly during the non-breeding season when the presence of lighted vessels increases. To mitigate these risks, vessel operators should minimize external lighting whenever possible and refrain from feeding birds, as this can lead to them congregating around vessels.
Walruses are also susceptible to injuries from vessel collisions, particularly during migration periods when they move in large groups. Vessel operators must be vigilant regarding the migration patterns of walruses, especially in critical areas like the Bering Strait, where these animals move from the Bering Sea into the Chukchi Sea.
Whales, due to their size and curious behavior, are vulnerable to collisions with offshore vessels. Such strikes can result in severe injuries or fatalities for the animals. Whales rely on open water or thin ice for breathing and can become trapped in sea ice when following leads created by vessels.
The risk of collision or entrapment is heightened during migration periods when whales transition between feeding and breeding grounds. These migratory routes are often protected areas, and vessel operators should be aware of seasonal restrictions and avoid these corridors when possible. Engaging with local indigenous populations can provide valuable insights into the migratory patterns of these animals.
Underwater noise generated by vessels is a significant environmental concern. This noise typically arises from machinery, hydrodynamic flow around the hull, propeller cavitation, and the sounds produced by breaking ice. The noise emitted by a vessel can be influenced by its age, installed power, hull design, and speed.
Marine vertebrates use sound for essential behaviors such as foraging, reproduction, predator avoidance, and navigation. Excessive noise can disrupt these activities, potentially affecting communication ranges among whales and other species.
When designing vessels for operation in sensitive areas, measures should be taken to minimize noise pollution. Considerations may include optimizing hull and propeller designs, implementing soft start motors, and applying specialized hull coatings. Increasingly, authorities are requesting noise profile assessments for vessels, which should be factored into the design and tendering processes for new builds.
In environments where ice is present, the utilization of Remotely Operated Vehicles (ROVs) and divers poses significant risks. The primary concern is the potential for umbilicals—essential cables and hoses connecting ROVs to support vessels—to be damaged or severed by drifting ice. To mitigate this risk, it is strongly recommended that all diving and ROV operations take place through a moon pool located within the hull of the vessel. This strategic approach effectively minimizes the interaction between operational equipment and ice, enhancing the safety of both divers and ROVs.
It is crucial for the moon pool area to have adequate dimensions and height to facilitate the installation and operation of a suitable Launch and Recovery System (LARS) for ROVs and divers. In icy conditions, divers must be equipped with hot water suits designed to provide warmth and protection. To ensure continuous operations, a minimum of two hot water machines should be available, allowing one unit to serve as a backup in case of failure. These hot water systems can be powered by either oil or electricity.
Effective risk management protocols must be established to protect personnel on the working deck. This includes regular inspections of divers' helmets and other personal equipment to ensure functionality in the expected temperature conditions. In colder environments, it might also be necessary to heat the breathing gas supplied to the divers. Battery performance can significantly diminish in low temperatures, so all batteries should be fully charged and tested under the specific cold conditions expected during the dive.
For divers who lack experience in cold-water diving, training in cold weather physiology and cold injury prevention is essential. Additionally, for surface diving operations, it is advisable to position the decompression chamber as close to the moon pool as possible—ideally on the same level. Access routes to this chamber should be kept clear of ice, snow, and other obstacles to ensure safe and efficient use.
In emergencies, plans should be in place to safely evacuate saturation divers from the vessel. This includes providing a hyperbaric evacuation system (HES) that has been tested and deemed suitable for arctic and sub-arctic conditions.
Currently, the feasibility of conducting 2D seismic survey operations is limited to areas with light to moderate ice concentrations. Although technologies are in development to enable seismic work under ice, these efforts are not yet applicable to vessels. For those engaged in seismic surveys, significant risks arise from ice potentially damaging towed arrays that can extend many kilometers and project hundreds of meters on either side of the vessel. These arrays are vulnerable to ice interaction, necessitating careful monitoring of the area ahead of the vessel to ensure it is clear of floating ice.
The industry has gained limited experience in pack ice scenarios, typically involving a seismic vessel towing only a single streamer while following an icebreaker. This method proves ineffective when faced with glacial ice featuring a deep keel unless additional vessels are available to tow icebergs out of the survey path. However, this is often impractical due to the need for rapid survey speed to prevent the streamers from sinking and the time-consuming process of towing an iceberg.
To enhance assurance during operations, ice radars can be employed, but primarily, this assurance is obtained through the use of chase vessels that scout ahead of the seismic vessel. If ice is detected, the chase vessel must alert the seismic vessel, which may need to alter its course to avoid the ice. Alternatively, the chase vessel might need to reduce the size of the ice to prevent damage. The seismic vessel's maneuverability is limited by the towed array, necessitating that any ice obstructions be identified several miles in advance. Moreover, the chase vessel's ability to manage ice is constrained by the need for the seismic vessel to maintain a forward speed of approximately 4-4.5 knots to ensure proper streamer floatation.
Moving offline can significantly disrupt planned survey lines; thus, comprehensive reconnaissance using chase vessels and potential helicopter overflights is highly recommended before deployment. In contrast, geotechnical surveys may tolerate a higher level of ice concentration, depending on the nature of the activities, the vessel's station-keeping capabilities, and any available ice management support. It's important to note that seismic activities can be particularly disruptive to wildlife, warranting consideration of wildlife interactions during planning.
Systems onboard accommodation vessels, such as freshwater supply lines, tanks, and sewage systems, require additional environmental protection to maintain functionality in extreme conditions. In the event of power loss, emergency generators should be appropriately sized to handle increased heating loads and provided with fuel suitable for the lowest anticipated temperatures. Batteries should also be included to ensure cold starting capability.
Depending on ice conditions, it may be necessary to consider launching arrangements for emergency craft onto ice, along with the provision of ice gangways and escape chutes. Personnel should be informed about the functionality of Emergency Position-Indicating Radio Beacons (EPIRB) and Personal Floatation Devices (PFD), which may not activate automatically when vessels are evacuated in ice-covered waters. Escape routes must remain clear of ice to facilitate safe evacuation.
Passengers must receive information regarding survival in icy environments and human physiological responses to cold. Adequate protective clothing, including gear for hands, eyes, and feet, should be readily accessible. Additionally, vessels should be equipped with proper waste disposal facilities, given the prolonged duration of operations and the limited availability of shore-based disposal options. This includes considering waste compactors and incinerators, as well as storage for treated oil, grey, and black water to comply with discharge regulations. The functionality of waste treatment systems may be compromised in freezing conditions.
During the laying of pipes and cables, caution must be exercised to avoid damaging equipment through ice contact. Furthermore, ice presence can impair the vessel's ability to maintain its position. Workers are also at risk of ice falling from heights during these operations, necessitating stringent safety measures.
In icy environments, side-launched fall pipes are at risk of damage from passing ice. Whenever feasible, deploying equipment through a moon pool should be considered. Workers must be provided with survival information related to icy conditions and cold exposure.
The capability of a drilling or coring vessel to operate in icy conditions is largely determined by the ice class of the vessel and the extent of ice management measures implemented. In instances where drilling occurs over extended periods in extremely low temperatures, the drilling rig must be winterized, and personnel should be safeguarded against wind chill. Providing heated areas on the drill floor is essential to ensure that rig workers have a place to warm up. Special attention should be given to protecting the workforce from the hazards of ice falling from the drilling rig, especially during freezing fog or ice accretion.
Equipment used for drilling must be assessed to ensure that materials, particularly steel, are rated for the extreme temperatures anticipated. When utilizing dynamic positioning (DP) for station-keeping, it is vital for the operator to confirm that the DP system can function effectively under the current ice conditions or that sufficient ice management resources are available to minimize ice impacts. The use of joystick control may enhance operational effectiveness in these challenging conditions.
When employing water-based drilling fluids, precautions must be taken to prevent freezing before, during, and after the fluid is introduced into the hole. The vessel's ability to quickly relocate in response to uncontrolled ice incursions is critical, ensuring that drilling operations can be secured and the vessel can safely depart the site if hazardous ice conditions arise.
For heavy lift operations, maintaining precise positioning of the lifting vessel during the lift is crucial. Ice can be advantageous in this context, as it may stabilize the vessel, reducing rolling. However, conducting lifts in extremely low temperatures necessitates that cranes and associated equipment are rated for the anticipated environmental conditions. It is essential to keep crane sheaves clear of ice to prevent the wire runners from derailing.
Offshore vessels may serve as primary or secondary oil spill response vessels (OSRVs) in their operational areas. It is vital for these vessels to be equipped with suitable gear capable of functioning in the anticipated icy conditions per the oil spill response plan. Response equipment must effectively recover oil from both icy water and the sea ice surface. This may involve activities such as in-situ burning, dispersant application, and the deployment of containment stacks.
Vessel tank capacities for recovered oily water require careful consideration, as shore facilities capable of receiving contaminated water may be scarce, especially in Arctic regions. Plans should include options for transferring oily water to an offshore installation or another vessel. Onboard storage should incorporate heating systems to facilitate oil/water separation and prevent freezing.
Given the ice concentration, deploying boom with small boats may not always be feasible. However, the ice itself can serve as a natural boom, allowing for areas to be cleared where the oil spill response vessel can operate effectively to recover oil trapped within the ice.
