Section 8 Functional requirements

8.1.1 This Section covers the basic functional requirements such as:

1. location of the OPTS on the mothership;
2. pedestals and foundation;
3. environmental conditions;
4. access arrangements (e.g. floorings, platforms, walkways, ladders, guards, guard-rails, handrails, stanchions, head height, gangway);
5. gangway protection;
6. ergonomics (e.g. Operator control station);
7. access control arrangements;
8. maintenance;
9. redundancy of components;
10. requirements for effective motion compensation;
11. safety equipment and evacuation arrangements;
12. motion control and limitation;
13. personnel containment and baskets;
14. stowage;
15. dropped objects;
16. fire safety;
17. hazardous areas; and
18. winterisation

    which shall be applied to the OPTS to be classed or certified to the requirements of this Code.

8.1.2 Proposals to deviate from the requirements of this Section will be specially considered.

8.1.3 The general design principle shall be that no single point failure in any part of the OPTS will result in hazards to the personnel being transferred, the Operator or other persons near the OPTS, or personnel on the mothership or the target unit.

8.1.4 The OPTS is further to be designed to cover the significant hazards as per ISO 12100 Safety of machinery – General principles for design – Risk assessment and risk reduction which are not dealt with in this Code. Moving or rotating parts shall not pose a mechanical hazard (e.g. crushing, shearing, cutting, etc.) to personnel to be transferred, the Operator or other persons.

8.1.5 For the design of the gangway particular attention is drawn to the torsional stiffness of the gangway structure forming an open U-shaped cross-sectional profile which will still have some torsional resistance. Such resistance can lead to external and internal forces which need to be considered.

8.2.1 The OPTS should be located clear of any working area unrelated to the personnel transfer operations.

8.2.2 The OPTS is not to be placed where cargo or other suspended loads may pass overhead of any configuration of the OPTS. However, if this cannot be avoided by design, it shall be ensured that personnel transfer operations are not conducted, and personnel are not on or near the OPTS at those times of operation.

8.3.1 Pedestals and their foundation are to be designed as per Ch 4, 5 Pedestals and foundations of the Code for Lifting Appliances in a Marine Environment, July 2022.

8.3.2 Where bolted connections are applied to connect the OPTS pedestal/foundation with the mothership structure, those bolted connections are to be designed to 75 per cent of the individual yield stress factors given in Ch 4 Cranes and Submersible Lifting Appliances Table 4.2.14 Allowable stresses for fitted bolts and Table 4.2.15 Allowable stresses for non-fitted bolts in the Code for Lifting Appliances in a Marine Environment, July 2022.

8.4.1 Hazards affecting the OPTS or its components and parts, originating from temperature effects, shall be taken into consideration. Reference is made to Ch 1, 10 Risk assessment.

8.5.1 Floorings shall be designed in compliance with a recognised National or International Standard (e.g. ISO 14122 Safety of machinery – Permanent means of access to machinery). In addition, the following requirements shall be considered and in case of conflict the more onerous requirement shall apply.

8.5.2 The surface of all floorings shall be supplied with non-slip material and/or surface. The slip-resistance shall be maintained when the flooring is wet or otherwise contaminated with substances reducing the friction coefficient.

8.5.3 The means of connection between the flooring structure and the gangways, walkways, waiting areas or similar structure shall avoid loosening and shall not pose a tripping hazard.

8.5.4 The gaps between the flooring components shall be small enough to prevent tripping and dropped objects. For guidance the gaps shall not be larger than the grating grid spacing, but less than 20 mm by 20 mm in any case.

8.5.5 The individual flooring segments shall be arranged at an equal surface level. To avoid unequal flooring levels the individual consecutive segments shall preferably be placed on a common support structure. The difference in elevation of the individual flooring segments shall be a maximum of 4 mm.

8.5.6 The area below the flooring shall be secured against dropped objects falling through grating flooring structures. Alternatively, sufficiently small grating mesh sizes shall be chosen, but less than 20 mm by 20 mm in any case.

8.5.7 The flooring structure shall be protected against corrosion, or other degradation in the case of non-metallic materials.

8.5.8 The design loads for floorings are provided in Ch 1, 3.5 Loads on floorings.

8.6.1 Platforms and walkways and similar arrangements shall be designed in compliance with a recognised National or International Standard (e.g. ISO 14122 Safety of machinery – Permanent means of access to machinery). In addition, the following requirements shall be considered and in case of conflict the more onerous requirement shall be applied.

8.6.2 For the purposes of these requirements waiting areas (if applicable) are considered as a sub-category of a platform or walkway.

8.6.3 The floorings of platforms and walkways shall be designed as defined in Ch 1, 8.5 Floorings.

8.6.4 Platforms and walkways shall not be inclined. If an inclined walkway cannot be avoided due to design restrictions the inclination angle shall be limited to ±5°.

8.6.5 The minimum effective width of walkways shall be 600 mm.

8.6.6 The minimum area for each person in the waiting area shall be 0,25 m².

8.6.7 Interface areas need to be designed in such a way to ensure that there will be no hazards for personnel due to relatively moving parts (e.g. crushing or shearing of body extremities such as feet and hands, etc.). Any deflections causing gaps between interface areas need to be taken into consideration in the design. Each interface area shall be marked with a warning pattern in black and reflecting yellow.

8.6.8 Platforms and walkways shall be enclosed by guard rails. The guard rails shall be equipped with means to avoid dropped objects from falling through the guard rails and their supporting structure. In case access through the guard rails is required a gate shall be fitted. Reference is made to Ch 1, 8.9 Guard rails, handrails and stanchions.

8.6.9 Where platforms and walkways can only be accessed via a ladder, means are to be provided to close the opening in the guard rails with a gate or similar means.

8.6.10 The design loads for platforms and walkways are provided in Ch 1, 3.6 Loads on platforms and walkways.

8.7.1 Ladders shall be designed in compliance with a recognised National or International Standard and EN 13586 Cranes – Access or ISO 14122 Safety of machinery – Permanent means of access to machinery shall be considered to be applied (as applicable).

8.8.1 Guards shall be designed in compliance with a recognised National or International Standard and ISO 14120 Safety of machinery – Guards – General requirements for the design and construction of fixed and movable guards shall be considered to be applied (as applicable).

8.9.1 Guard rails, handrails, stanchions, and similar arrangements shall be designed in compliance with a recognised National or International Standard (e.g. ISO 14122 Safety of machinery – Permanent means of access to machinery). In addition, the following requirements shall be considered and in case of conflict the more onerous requirement shall be applied.

8.9.2 Handrails shall be made of continuous rigid solid or hollow sections. The handrail material shall be metal, but other materials will be specially considered.

8.9.3 Guard rails, stanchions or similar side supporting structures are to be permanently connected to the gangway or walkway structure. Stanchions shall be fitted in equal distances of a maximum of 1500 mm. Smaller distances may need to be applied in order to fulfil the requirements as stipulated in Ch 1, 8.9 Guard rails, handrails and stanchions 8.9.1 and Ch 1, 8.9 Guard rails, handrails and stanchions 8.9.2.

8.9.4 The minimum height of the handrail or top guard rail above flooring level for gangways, walkways and waiting area shall be 1100 mm. There shall be at least two intermediate guard rails (or similarly effective arrangements) provided between the top guard rail and the flooring, each being not more than 380 mm apart. The distance from the top of the toe plate to the lowest guard rail shall not be more than 230 mm. The height of the top guard rail may need to be increased as a result of the risk assessment (e.g. in case of significant lateral or vertical accelerations posing a hazard to personnel). In case of a top guard rail height above 1100 mm, additional intermediate guard rails shall be provided with a maximum spacing of 380 mm. In case of a top guard rail height above 1100 mm, a handrail is to be provided at a height between 900 mm and 1100 mm. Rails which are used as a handrail are to be uninterrupted and easy to grasp.

8.9.5 Toe plates with a minimum height of 100 mm are to be fitted in way of steps and walkways.

8.9.6 The design loads for walkways are provided in Ch 1, 3.7 Loads on handrails.

8.9.7 Gates shall be designed in compliance with a recognised National or International Standard (e.g. ISO 14122 Safety of machinery – Permanent means of access to machinery). In addition, gates shall be provided with a self-locking device that will restrain the gate from accidental opening.

8.10.1 The minimum head height over platforms, walkways and gangways shall be 2100 mm.

8.10.2 The head height shall not be reduced due to obstacles in way of platforms, walkways and gangways, such as gaps between interfaces.

8.11.1 The gangway shall be designed in compliance with a recognised National or International Standard and ISO 5488 Ships and marine technology – Accommodation ladders and ISO 7061 Ships and marine technology – Aluminium shore gangways for seagoing vessels shall be considered to be applied (as applicable). In case of conflict between an applied recognised National or International Standard the requirements of this Code shall be applied.

8.11.2 The minimum effective width of the gangway shall be 600 mm for A-GR and 1200 mm for A-GU type systems.

8.11.3 Interface areas need to be designed in such a way to ensure that there will be no hazards for personnel due to relatively moving parts (e.g. crushing or shearing of body extremities such as feet and hands, etc.). Interface areas include, but are not limited to:

1. Between the OPTS base frame and the motion compensation and/or pedestal;
2. within the motion compensation system;
3. between the gangway and the OPTS base frame;
4. between the main and telescopic part of the gangway (if any);
5. between the gangway tip and the target structure; or
6. between other similar interface areas of relatively moving parts.

Any deflections causing gaps between interface areas need to be taken into consideration in the design. Each interface area shall be marked with a warning pattern in black and reflecting yellow.

8.11.4 Gaps between gangway and base frame, between the main and telescopic part of the gangway, between the gangway tip and the target structure or similar arrangements posing a hazard of falling through, need to be secured by means of structural barriers such as guard rails.

8.11.5 The design of areas of moving parts (e.g. luffing or telescoping hydraulic cylinders) needs to ensure that hazards for personnel are prevented.

8.11.6 Protruding parts in way of walkways, waiting areas or similar arrangements, which may result in tripping or other hazards, shall be avoided by design. Alternative solutions by means of marking will be specially considered.

8.11.7 The side supporting structure shall be equipped with means preventing objects from falling from the gangway, such as safety nets or similar. Such arrangements may be omitted in case of non-perforated structural designs (e.g. side plating) instead of a lattice structure.

8.11.8 Hydraulic piping and/or hoses need to be secured to avoid accidental damage by personnel or cargo trolleys moving along the gangway.

8.11.9 The design of rope reeving arrangements needs to ensure that hazards for personnel due to running ropes or turning sheaves are avoided.

8.11.10 During the personnel transfer operation the preferred angle of the gangway relative to the horizontal plane shall be within +10° and -10°. The maximum personnel transfer operation gangway inclination shall be limited to be within +20° and -20°. The application of other personnel transfer operation gangway angles will be specially considered.

8.11.11 The gangway may be subjected to larger angles while not operating in personnel transfer mode, e.g. in case the system is also used as a conventional offshore crane (e.g. ST-C type systems). In such cases the simultaneous use of the personnel transfer mode and the offshore crane mode shall be prohibited.

8.12.1 The OPTS shall be equipped with a lateral gangway protection system ensuring that the design sideways forces are not exceeded during active slewing operations.

8.12.2 The OPTS shall be equipped with a vertical gangway protection system ensuring that the design forces are not exceeded during active luffing operations.

8.12.3 Active motion compensation systems which are controlling the motions of the gangway and the contact forces between the gangway tip and the target structure may be regarded as being equipped with a gangway protection system.

8.12.4 OPTS which are in free floating mode may be regarded as being equipped with a gangway protection system as long as there are warnings when the system is approaching its limits.

8.13.1 The OPTS is required to include a dedicated Operator control station which shall comply with the requirements of a recognised National or International Standard and the application of EN 13557 Cranes - Controls and control stations shall be considered (as applicable).

8.13.2 If the Operator control station is provided inside an Operator’s cabin, the Operator shall be protected from the environmental influences as follows:

1. temperature (heat and cold);
2. noise and vibration;
3. direct sunlight;
4. humidity;
5. wind;
6. rain;
7. snow;
8. ice; and
9. other environmental influences.

The details of the required environmental protection level shall be agreed in each case.

8.13.3 The Operator’s cabin, if provided, shall further:

1. provide suitable space to enable the Operator to operate the OPTS;
2. as far as practicable, be made of fire-retardant or fire-resistant materials, to a recognised Code or standard, e.g. IMO International Code for the Application of Fire Test Procedures (2010 FTP Code), etc.;
3. be suitably ventilated;
4. enable the windows to be defrosted and defogged;
5. have window wipers fitted enabling an unobstructed view of the walkways, gangway, gangway tip and target structure;
6. have an ergonomically designed adjustable seat, including the arrangements of the controls (see Ch 1, 8.13 Operator control station 8.13.7); and
7. be provided with an emergency means of escape in addition to the main access route.

8.13.4  The Operator cabin, if provided, shall comply with the requirements of a recognised National or International Standard and the application of EN 13557 Cranes - Controls and control stations shall be considered (as applicable).

8.13.5 The design of the control station shall allow the Operator to have an unobstructed view of the walkways, gangway, gangway tip and target structure.

8.13.6 The persons at the control station e.g. Operator, shall be protected from dropped objects. Further protection shall be provided at the control station to prevent persons from falling from height.

8.13.7 The main control panel shall be equipped with the following marked and illuminated controls and indicators:

1. Start/stop of OPTS;
2. interlock preventing the simultaneous operation of the main control panel and a remote or secondary control panel (if applicable);
3. emergency stop;
4. control levers for manual movement of the gangway (e.g. luffing, slewing, telescoping, vertical, horizontal, travelling motions – all as applicable);
5. access control;
6. emergency opening of access control (if applicable);
7. switch to disable/enable motion compensation;
8. dead man switches (only required in case of single Operator ST-A and ST-H systems);
9. indication of whether the system is within operational design limits (including a display of trends);
10. display of alerts using appropriate visual indicators and audible signals (see Ch 1, 9.4 Active systems (ST-A or ST-H) 9.4.7);
11. crane related controls, indicators, switches and information (if applicable); and
12. mode indicator in case the OPTS fulfils several different functions (e.g. ST-H and ST-C).

8.13.8 A Secondary (emergency) means of control shall be provided in cases of failure of the main control panel. The activation of the secondary means of control and the changeover of control over the OPTS shall be possible without undue delay. In case of active systems (ST-A or ST-H), the secondary means of control shall take account of the requirements of Ch 1, 9.4 Active systems (ST-A or ST-H) 9.4.4. Reference is further made to Pt 6, Ch 1, 2.2 Control stations for machinery 2.2.6 and Pt 6, Ch 1, 2.2 Control stations for machinery 2.2.7 of the Rules and Regulations for the Classification of Ships, July 2022.

8.13.9 In case of hydraulically driven OPTS, the control station shall be equipped with a manual hydraulic control. The manual hydraulic control may be regarded as a secondary (emergency) means of control.

8.13.10 For cableless remote-control panels reference is made to Ch 1, 9.2 General 9.2.5.

8.14.1 Access control arrangements are to be installed for all OPTS which are designed for a limited number of persons allowed simultaneously on the gangway or walkway.

8.14.2 If the access control system is designed as a physical barrier such as a crossing gate system an emergency means of opening needs to be implemented for each barrier at the barrier and at the control stations.

8.14.3 Reference is made to Ch 1, 9 Electrotechnical systems.

8.15.1 All parts and components of the OPTS are to be designed to allow for regular and irregular maintenance. All parts and components need to be readily accessible and if necessary, allow for all required inspection and maintenance activities, such as checking and monitoring of systems and components status, lubrication, repair and exchange of parts or components.

8.15.2 Every OPTS is to be constructed so as to reduce routine maintenance to a minimum. Those parts requiring regular maintenance are to be readily accessible and easily maintained by the mothership’s crew or Operator.

8.15.3 The maintenance system shall allow the identification of any trends which may support the resolution of systematic maintenance related aspects of the OPTS.

8.15.4 The guidelines as provided in ISO 12478-1 Cranes – Maintenance manual – Part 1: General shall be taken into consideration.

8.15.5 For further information about the scope of thorough examination (incl. maintenance aspects) see Table 1.13.2 6-Monthly thorough examination of OPTS.

8.16.1 As outlined in Ch 1, 1.1 Introduction 1.1.6, the lifting and supporting of persons with machines in an offshore or open-sea environment is regarded as an application posing higher risks for personnel compared to normal cargo handling operations.

8.16.2 For the purposes of decreasing the probability of occurrence of harm and failure the concept of EN 13135 Cranes – Safety – Design – Requirements for equipment, clause 5.9 shall be applied. This can be achieved by the application of a risk coefficient or by duplication of components. The specification of an enhanced inspection and maintenance programme or an upgrade of the level of quality control alone is not considered to be sufficient as a risk reduction/mitigation measure.

8.16.3 The general principles and steps of risk reduction measures are described in ISO 12100 Safety of machnery – General principles for design – Risk assessment and risk reduction, clause 6.

8.16.4 The concept and application of risk coefficients is described in EN 13001-2 Cranes – General design – Part 3-2: Limit states and proof of competence of wire ropes in reeving systems, clause 4.3.2 and Annex D.

8.16.5 As a general principle and for safety critical components, the redundancy of components of the OPTS shall be such that no single point failure will lead to a failure of any further component, an uncontrollable situation, or uncontrolled motion of the OPTS. There shall be no hazard to any personnel in case of a single point failure.

8.16.6 Two fully redundant means of luffing shall be established in the design of the OPTS. This can be by means of two hydraulic cylinders, either one of which being capable of holding and luffing the gangway but not required to motion compensate.

For a definition of the original risk coefficients γ_n.SWL, γ_n.UDL and γ_n.DL see Ch 1, 3.8 Risk coefficient.

8.16.9 The risk coefficient shall be applied in all operational load cases.

8.16.10 The redundancy of the stowage arrangements or parts of the stowage arrangement shall also be taken into consideration in case the failure of any single part will lead to an uncontrollable release of the OPTS or any part of the OPTS.

8.16.11 A single hydraulic cylinder (including pins) and the associated hydraulic system and associated supporting structure shall be subjected to an enhanced inspection and maintenance regime.

8.16.12 The redundancy requirements for telescopic arrangements and drives will be specially considered.

8.16.13 The redundancy requirements for arrangements directly used for motion compensation will be specially considered.

8.17.2 In case a DP system is not fitted it is to be demonstrated that the motion compensation performance of the OPTS is sufficient for the intended environmental conditions.

8.17.3 In order to provide the basis for effective active motion compensation of the OPTS, the motions of the mothership and (if applicable) the motions of the target unit need to be measured and the data needs to be provided for processing by the OPTS control system. The actual motions of the OPTS shall be monitored in order to ensure that the design operating envelope of the OPTS is not exceeded during operations.

8.18.1 The design of the access arrangements to the OPTS shall be such that specialist personnel protective equipment (e.g. harness) is not required.

8.18.2 Additional Flag State, Coastal State Authority, Owner or Operator requirements are to be considered.

8.20.1 The operational motion limits defined in Ch 1, 8.20 Motion monitoring 8.20.3 and Ch 1, 8.20 Motion monitoring 8.20.4 shall be applied.

8.20.2 The compensated motion shall be continuously monitored and recorded by the control system throughout the transfer operation and at least for a period of ten minutes prior to transfer operations. Operational motions are inherently statistical, therefore an appropriate statistical method shall be applied to provide for safe transfer operations. The statistical method is to determine the probability of exceeding the operational motion limits provided in Ch 1, 8.20 Motion monitoring 8.20.3 and Ch 1, 8.20 Motion monitoring 8.20.4, during a representative transfer period of a minimum of ten minutes. The captured motion data shall be analysed by the control system and an alarm sounded if the probability (evaluated by the statistical model/method) of exceeding any limit is greater than P = 10^-3, to indicate that personnel transfer shall be suspended until motions are back within the defined limits. The probability level of P = 10^-3 is applied as a minimum for acceptable risk with reference to LR’s ShipRight Procedure for Risk Based Certification (RBC).

8.20.3 During transfer of personnel, the following acceleration limits shall be applied by the control system using an appropriate statistical control method based on the expected peak values. These limits shall apply at all points on the OPTS including the gangway:

1. vertical acceleration: 2,0 m/s²; and
2. horizontal acceleration: 1,0 m/s².

8.20.4 During transfer of personnel, a velocity limit of 0,5 m/s shall be applied by the control system using an appropriate statistical control method based on the expected peak values. These limits shall apply at all points on the OPTS including the internal movements of the gangway, e.g. due to movement of the telescopic part of the gangway.

8.20.5  During the transition between uncompensated and compensated states the access control system shall clearly indicate that personnel transfer is not permitted.

8.20.6 Deviations from the requirements in Ch 1, 8.20 Motion monitoring 8.20.2 to Ch 1, 8.20 Motion monitoring 8.20.4 will be specially considered.

8.21.1 Suspended baskets as part of the personnel handling functionality of the OPTS functioning as an offshore crane (see Ch 1, 1.10 Terms and definitions 1.10.3) shall be designed and certified for this purpose.

8.21.2 Personnel containments supporting personnel to be transferred as part of the OPTS (see Ch 1, 1.10 Terms and definitions 1.10.38) shall be designed for this purpose and will be assessed together with the OPTS being certified or classed.

8.21.3 Cargo baskets shall be designed to safely contain the intended objects considering the motions and loads as applicable at the intended location on the gangway (e.g. gangway motion and accelerations).

8.22.1 The OPTS needs to be supplied with a dedicated stowage concept/arrangement for general transit/voyage and in-field transit (see Ch 1, 4.3 General transit/voyage (stowage/survival) and in-field transit load combinations).

8.22.2 The design of the stowage concept/arrangement shall cover the following aspects as a minimum:

1. The gangway or personnel containment of the OPTS shall be designed to have a designated stowage position and means of securing are to be provided.
2. The machinery systems of the OPTS shall be designed to be able to be disconnected from their power source and means of securing are to be provided.
3. Means of stowage/securing are to be provided for all other equipment and components where there is a hazard that they may become loose during general transit/voyage or in-field transit.

8.22.3 Depending on the OPTS type and design it may be acceptable for in-field-transit that a less strict securing regime is applied. For example, it might be acceptable that the gangway is only supported by the luffing systems and the gangway slewing is arrested by drive brakes for in-field-transit cases. However, in such cases it is to be ensured that proper weather window information is obtained in order to ensure that the design loads for the system are not exceeded and/or hazardous situations, such as uncontrolled gangway movements, are avoided in all cases.

8.23.1 This sub-Section refers to dropped object hazards originating from the OPTS.

8.23.2 All non-welded items need to be assessed for the risk of becoming dropped objects. Bolted connections pose a particular hazard and need to be assessed with particular attention.

8.23.3 Components, parts and equipment which are exposed to vibrations, impact or motions are to be secured in case there is a hazard that those items become dropped objects.

8.23.4 The instructions for use shall also address the hazard of objects dropped by transferring personnel, Operators and other personnel working on the OPTS. The instructions for use shall include guidance on limiting the risk of dropped objects. Examples for such dropped objects are:

1. From transferring personnel, OPTS maintenance personnel, inspectors, Surveyors, etc:

   carried tools and other objects/parts/components/spare parts, parts of the PPE, etc.

2. From OPTS Operators:

   PPE, remote controls, etc.

8.23.5 Reference is made to ANSI/ISEA 121 American National Standard for Dropped Object Prevention Solutions for general guidance concerning dropped objects.

8.24.1 This sub-Section refers to dropped and moving objects posing a hazard to the transferring personnel, the Operator and any part of the OPTS (including the control panel).

8.24.2 With respect to moving objects, the following shall be considered as a minimum:

1. objects hoisted and slewed by cranes that may come into contact with the OPTS;
2. fixed objects that may come into contact with the moving OPTS.

8.24.3 Risks due to dropped and moving objects shall be mitigated in the following order of measures:

1. By means of design: e.g. structural protection, position of the OPTS on board.
2. By means of individual risk assessment: e.g. instructions for use shall require that the hazards due to dropped and moving objects are considered prior use.

8.24.4 Reference is made to ANSI/ISEA 121 American National Standard for Dropped Object Prevention Solutions for general guidance concerning dropped objects.

8.25.1 The main structural components of the OPTS are to be made of non-combustible material (i.e. steel). The use of other materials will be specially considered.

8.25.2 The active and passive fire protection arrangements and design are to be in compliance with the requirements of the mothership, e.g. Chapters 8.3 and 9 of IMO Code for the Construction and Equipment of Mobile Offshore Drilling Units (2009 MODU Code) and Chapter II-2 of IMO International Convention for the Safety of Life at Sea (SOLAS), 1974, etc. as applicable to the mothership.

8.25.3 Further to the mothership’s stipulated requirements for active and passive fire protection arrangements, reference should also be made to any potential requirements of the OPTS interfaced with offshore hydrocarbon production and/or drilling installations, e.g. ISO 13702 Petroleum and natural gas industries – Control and mitigation of fires and explosions on offshore production installations, ISO 19353 Safety of machinery – Fire prevention and fire protection, etc. However, the intended position of the mothership and the planned location of the OPTS interface to the offshore installation is to be in a location outside the range of any credible accidental loads, e.g. explosion blast loads, fire, dropped objects, etc. This is considered to require particular attention for OPTS used with offshore hydrocarbon production and/or drilling installations.

8.25.4 For the aspects of fire protection of the control station the requirements of EN 13557 Cranes – Controls and control stations are to be satisfied.

8.25.5 Hydraulic oil tanks and filters are not to be situated immediately above boilers or other highly heated surfaces.

8.25.6 Hydraulic oil pipes, pumps, filters and other hydraulic components are not to be installed above or near high temperature equipment or other sources of ignition or onto rotating machinery parts. Where necessary, shielding is to be provided and the arrangements are to allow easy access for routine maintenance. Hydraulic oil pipes should also be installed and screened, or otherwise suitably protected, to avoid oil spray or oil leakages onto hot surfaces, into machinery air intakes, or onto other sources of ignition such as electrical equipment. Pipe joints are to be kept to a minimum and where provided are to be of a type acceptable to LR. Pipes are to be led in well lit and readily visible positions.

8.25.7 Firewater hydrant cover over the OPTS gangway/access ways may be assessed and dispensed with, if the determined fire risks over these locations are considered to be low.

8.26.1 If the OPTS is operating in hazardous areas where explosive atmospheres may be present the requirements of this Section shall be satisfied.

8.26.2 The identification of hazardous situations shall be carried out as per the requirements of a recognised standard (IEC 60079-10-1 Explosive atmospheres - Part 10-1: Classification of areas - Explosive gas atmospsheres, EN 1127-1 Explosive atmospheres - Explosion prevention and protection - Part 1: Basic concepts and methodoloy, etc.).

8.26.3 Electrical equipment shall be in compliance with the requirements as detailed in IEC 60079 Explosive atmospheress series of standards and IEC 60079-14 Explosive atmospheres - Part 14: Electrical installations design, selection and erection in particular.

8.26.4 Non-electrical equipment shall be in compliance with the requirements as detailed in ISO 80079-36 Explosove atmospheres - Part 36: Non-electrical equipment for explosive atmospheress - Basic method and requirement.

or established through distribution modelling.

8.26.6 In the case of an OPTS intended to form part of an offshore installation’s evacuation arrangement, as detailed in Ch 1, 8.19 Evacuation arrangements, where the design intent of the OPTS and associated mothership is that they would remain in place during an installation incident, as part of a planned offshore installation evacuation route/system, then the hazardous regions associated with the interfaced offshore installation needs to be fully considered. The intended position of the mothership and the planned location of the OPTS interface with the offshore installation is to be in a location outside the range of any credible accidental loads, e.g. explosion blast loads, fire, dropped objects, etc. This is considered to require particular attention for OPTS used with offshore hydrocarbon production and/or drilling installations. For such OPTS, evacuation route arrangements for hydrocarbon production and/or drilling installations, any electrical equipment for the OPTS which has to remain operational during a Major Accident Event (e.g. rupture of an offshore installation process vessel or pipe), whether or not installed in a hazardous zone or location, is to be suitable for use in an explosive gas atmosphere. Such equipment is to be of a type permitted within Zone 1 locations, unless it is demonstrated that the equipment is appropriately protected against potentially coming into contact with a flammable atmosphere by being located in an enclosed safe area with appropriate mitigating measures. Mitigation methods acceptable to LR for enclosed safe areas may include, but are not limited to:

1. equipment installed within enclosure with suitably sealed barriers and doors, with an adequate level of smoke integrity (i.e. ‘A’ or ‘H’ fire rated divisions, as per IMO International Code for the Application of Fire Test Procedures (2010 FTP Code) or IMO Code for the Construction and Equipment of Mobile Offshore Drilling Units (2009 MODU Code)) and gas tightness;
2. rated gas dampers (gas tight to ISO 15138 Petroleum and natural gas industries - Offshore production installations - Heating, ventilation and air-conditioning stated requirements);
3. suitable gas detection located at associated air intake ducts, with associated trip/closure logic; and
4. enclosure positive pressurisation.

Other arrangements may also be submitted for consideration by LR. For further guidance regarding such arrangements, see Pt 7, Ch 1 Safety and Communication Systems and Pt 7, Ch 2 Hazardous Areas and Ventilation of the Rules and Regulations for the Classification of Offshore Units, July 2022.

8.27.1 Systems which are specially designed to operate in arctic conditions shall comply with the requirements of this sub-Section. The requirements of this sub-Section are related to winterisation level Winterisation C(t), which is associated with an operational scenario of short duration transits in low temperatures, e.g. ships loading/discharging in low temperatures then sailing to discharging/loading in warmer regions. More severe operational scenarios will require special consideration beyond the requirements of this sub-Section.

8.27.2 Irrespective of winterisation, for general worldwide service OPTS are to be designed to a minimum design temperature of −10°C or lower. Reference is made to Ch 4, 2.25 Materials of the Code for Lifting Appliances in a Marine Environment, July 2022.

8.27.3 If the OPTS is intended to be used in environmental conditions where significant amounts of snow and ice are present the requirements of this sub-Section are to be complied with. See also LR’s Rules for the Winterisation of Ships, July 2022.

8.27.4 For all areas other than gangway and machinery the effects of ice and snow are to be considered and are to be mitigated by design or instructions for removal.

8.27.5 The OPTS is to be freed from snow and ice as far as possible unless the adverse effects of snow and ice are considered in the design of the OPTS. Examples for special design for winterisation of the gangway could be a fully enclosed gangway where the accumulation of snow and/or ice has been considered in the design.

8.27.6 The accumulation of ice and snow on the machinery components shall be considered and if the removal of ice and/or snow is not possible any adverse effect shall be eliminated by design (e.g. covering of machinery parts).

8.27.7 See also Ch 1, 1.4 Definitions 1.4.7, Ch 1, 5.1 General 5.1.2 and Ch 1, 5.11 Ice removal and prevention measures (as applicable) of LR’s Rules for the Winterisation of Ships, July 2022 concerning of ice removal and prevention measures.

8.27.8 Means are to be provided for habitable working conditions in Control cabins, where fitted, by providing internal space heating arrangements. Cabin windows are to be provided with heating arrangements to protect from the build-up of ice, see Ch 1, 5.8 Winterisation of spaces/compartments 5.8.1 and Ch 1, 5.8 Winterisation of spaces/compartments 5.8.3 of the Rules for the Winterisation of Ships, July 2022. Ice removal measures are to be provided to protect against icing. Window wiper operating devices are to be arranged inside the cabin or to be provided with heating arrangements.

8.27.9 Exposed control panels are to be provided with suitable steel covers to protect against icing.

8.27.10 Electrical installations are to comply with Ch 1, 5.6 Winterisation of electrical installations of the Rules for the Winterisation of Ships, July 2022.

8.27.11 For hydraulically operated equipment and systems, steam ice removal measures (or other means) are to be provided for protection against icing.

8.27.12 Measures are to be provided to protect against freezing of fluids, such as lubricants and hydraulic oil. The fluids are to be suitable for low temperature operation, and heating arrangements are to be provided where appropriate.

8.27.13 Hydraulic control systems are to comply with Ch 1, 5.4 Winterisation of auxiliary machinery systems and deck working areas of LR’s Rules for the Winterisation of Ships, July 2022.

8.27.14 Suitable provisions for cold start arrangements for exposed deck cranes are to be provided. Suitable lubrication oils and greases, circulation facilities for hydraulic oils and a flushing system for the hydraulic oil are to be provided.

8.27.15 Material grades are to be in accordance with the requirements of Ch 1, 12 Materials and fabrication and suitable for operation at the external design air temperature.