EPC Offshore Substation (OSS) Topside Technical Specification C256-EQ-Z-SP-00009Offshore substation (OSS) topside design, system and equipment technical and functional requirements for engineeringThis document targets all personnel that shall do work, follow-up deliveries or provide equipment/systems to the two, completely segregated, MWF Bałtyk II & MWF Bałtyk III offshore substations.The objective of this specification is to detail the functional and technical requirements for the MFW (BII) and MFW (BIII) OSS topsides. The Offshore Substation (OSS) Substructure Technical Specification can be found in /4/.This specification shall be read in conjunction with all the the Project Specific technical requirements listed in Appendix E.The MFW Bałtyk II and MFW Bałtyk III Design Basis Error! Reference source not found., set the design premises and principles for developing the OSS.The design shall incorporate Operations and Maintenance Requirements /20/ where applicable to the OSS. Any conflict between these requirements and other specifications/standards or industry best practice shall be highlighted for Company review.The design of the OSS shall adhere to Polish rules and regulations. If conflict: Polish rules and regulations shall prevail.All platform services and utilities which impact the availability of the transmission system, through failure or maintenance, shall be designed with redundancy.The design of the OSS shall be based on DNV-ST-0145; Offshore substations /2/ including references to other standards and guidelines, and shall be used to supplement gaps in the Polish rules and regulations where relevant. The technical requirements herein shall complement with /2/, and if in conflict, the Contractor shall inform Company.The OSS topside shall be designed as one unit to be fully assembled and pre-commissioned at onshore yard as far as reasonably practical.The design shall facilitate all foreseeable work in a safe and efficient manner covering all phases. The general design is described by the following:• Enclosed platform design – minimize amount of equipment located outdoor• Integrated remote control and monitoring including condition monitoring of all main equipment• Minimize environmental impact through all phases and lifetime of plant• Facilitate for night shift work and during cold periods• Access/egress via Crew Transfer Vessel (CTV), Service Operation Vessel (SOV) and Jack-up Rig (JUR)• Secondary escape via helicopter winching and tertiary via chute/raft.The POB for the offshore substation shall be optimized through all phases of the plant targeting 12 POB during operational phase and 24 POB during hook-up, commissioning and initial operation phase. In addition, there shall be extra safety equipment for 12 persons (total of 36 persons) on board during the hook-up, commissioning and initial operation phase. The target of 12 POB in operational phase is dependent on the number of subsuppliers being introduced in the EPC process. The design maintenance requirements will drive manning levels.The final optimized POB for the individual phases shall be agreed with Company.Additional equipment and facilities may be brought onboard to increase the POB during campaigns and temporary phases to minimize the design POB.The offshore substation shall achieve a safe and efficient design to ensure maintenance and operation friendliness by:• selecting concepts requiring minimum amount of topside equipment and man-hours for maintenance• selecting equipment with high quality in materials, high durability and low maintenance requirements with proven track record for similar use in offshore applications• designing systems with redundancy to minimize consequence of failures and maintenance without impacting plant availability• designing systems such that faults do not need rectification until next planned maintenance visit and repair/maintenance of equipment or system does not interfere with other equipment or systems• utilizing condition monitoring systems, remote testing and/or additional sensors/signals where practically possible to increase availability and reduce required man-hours offshore• ensuring remote testing and remote control from onshore Central Control Room (CCR) can be performed without risk of causing any disturbance in operation or loss of plant availability• minimize requirement for enhanced training of maintenance personnel. This entails:o aim to design systems and select equipment that does not require special training/certification to perform maintenance or repair o material handling design which minimize use of main platform crane o minimize requirement for tools/equipment that require special training/certification• considering climatic conditions to ensure operability all year, by appropriate level of winterisation and protection against adverse weather• selecting concepts and plant design to accommodate an efficient and safe decommissioning at end-of- lifeRefer to safety strategy for risk mitigation and safety barriers requirements, /17/.The maintenance shall guarantee safe and operable equipment, achieve legislative compliance, ensure equipment integrity and maintain equipment warranty. Effective maintenance relies on carrying out the right maintenance, at the right time, for the right cost and with the right resources.The wind farm shall be routinely maintained by utilising a Crew Transfer Vessel (CTV), with the future possible use of a Service Operations Vessel (SOV) for campaign-based inspection and maintenance. Winching of personnel to/from the OSS with helicopter, in case of emergency, shall be facilitated.High frequency maintenance activities (e.g. monthly, quarterly) shall be avoided, with the aim of no more than 12-month maintenance frequencies. The exception to this shall be when relevant laws and regulations require more frequent inspections. Outages impacting transmission system availability shall be no more frequent than once every 3 years.Sufficient redundancy and durability of equipment shall be designed into systems to maximise availability and minimise unplanned visits, with the aim that common faults do not require rectification until the planned annual/3 yearly maintenance visit (as applicable).Where temporary equipment is required for any routine maintenance, it shall be clearly defined and specified in relevant documentation. The most practical, safe and cost-efficient solutions shall be considered when it comes to if temporary equipment and tools shall be brought from shore or installed/stored offshore.For general requirements for working environment, reference is made to /15/.All equipment and areas shall have safe and efficient access for plant operations and maintenance in accordance with ISO 14122:2016, parts 1-4 /11/.• Protruding objects shall be avoided in walkways, access ways, escape routes and transportation ways• Walkways, access ways, escape routes, transportation ways, laydown areas, plated decks and workspaces shall have anti slip surfaces• Risk for falling ice and falling snow shall be assessed for work areas, access ways, transportation ways and escape ways and if necessary, mitigating actions shall be implemented.• Where possible, the platform design shall avoid steps and ladders to create a step-less working environment. Door thresholds shall be removable if used• Stairs shall be used when possible, instead of ladders• Manholes and confined spaces shall be avoided where practically possible• No areas are allowed where rescue-up is the only evacuation strategy• Location of equipment and instruments to be carefully chosen to enable safe and efficient maintenance: o Visual displays, gauges, level glasses etc. shall be easy to read from ground levelo Access to perform maintenance and inspections shall be possible from ground level or with suitable fixed access method. Where this is not practical or possible Company shall be consulted o Access to operate equipment shall be from ground level or with permanent access platform o Requirement to use scaffolding for access is not accepted for regular maintenance activities o No offboard access needs or working at height close to platform edges triggering need for man- overboard stand-by vessel. Where this is not practical or possible Company shall be consulted o The operators reach to equipment shall be <= 500 mm o At work position, ensure a 700 mm clearance for working (maintenance space)• It shall be possible to operate outdoor handles, switches etc. while wearing gloves• In case scaffolding or other temporary aids are needed either during hook-up or planned maintenance, support brackets / attachment points on the structure shall be included as requiredFall protection systems shall cover the complete topside and substructure through all phases ensuring the personnel are always protected from falling from any height. This includes also local fall protection systems on equipment and structures where access is required to operate equipment or perform planned maintenance.Selected fall protection systems shall be reported to and agreed with Company in early design stage to enable Company to standardize.In the boat landing access area, special considerations shall be given to the design of handrails and stanchions in order to support fall arrest system and anchor points. Extent of this additional requirement is based on the design where further recommendation from the designer is expected.All connections between elements shall be securely fixed by lock nuts and through bolts, or self-tapping screws. Setscrew type connections are not acceptable as permanent fixing method. The fixed connections shall not loosen or weaken by normal use, wind or platform vibrations.All handrails and guardrails shall be solidly designed for personnel protection and shall resist the accidental impact of a falling person, in any direction and at any point.The installed hand and guardrail system and stairs and ladders, complete with all its parts and fixing details, shall be maintenance free. Secondary retention (such as double nuts etc) shall be considered for all fixings where possible. Materials shall be in accordance with the materials selection philosophy, /7/.The multi-barrier principle shall apply for the complete hand and guardrail system and stairs and ladders, where a single fault shall not cause a system failure. Any weaknesses or faults developed over time shall be detectable by visual inspection.Caged ladders (ladders with back scratcher) shall not be used. Other types of fall arrest systems shall be used. Inclined ladders should be avoided. Fall arrest system Each OSS shall be equipped with sufficient fall arrest systems.The mounting location of the fall arrest system shall ensure suitable access for installation and maintenance purposes of these systems. The equipment shall be located high enough to reduce the possibility of collision with personnel when connecting/disconnecting from the system.All fall arrest systems shall be certified for outdoor use and storage (marine environment).The rescue and evacuation systems (descender devices for rescue) and Fall Arrest Self Retracting LifeLines shall be delivered according to the relevant standard.External fall arrest tether line systems should be of simple type, with all units on ladders to sea with a weak link between tether line and fall arrest device. Bottom bracket for tether line system should be at Highest Astronomical Tide (HAT) line.For all relevant areas where a fall prevention system is not practical and a fall arrest system shall be used, it shall be assessed whether a permanent device or an anchor point for a device shall be made.Suitable rescue device anchor points shall be above all fall arrest devices and attachment points. The anchor point of the fall arrest system at the upper section of the ladder shall be made of coated stainless steel to avoid corrosion happening as a result of coating damage when servicing the system.Where possible, anchor points shall be designed to always allow for the lowest fall factor.Anchoring points shall be located on locations where the danger of falling exists and no guard-rail can be constructed (e.g. a hatch or gate-opening, a platform, a ladder end).The location of the anchor points shall consider the positions that personnel are required to stand in order to stabilize loads, the maximum length of fall arrest lanyard, and the anchor point is required to be of suitable dimension to allow a hook to be connected.Fall arrest equipment and systems shall be of modular design to allow for offshore maintenance and certification.Guidance note: Anchor point: point on an anchor device or structural anchor used for the connection of personal fall protection equipmentAnchor lanyard: lanyard connected to the main attachment point of the harness, which normally incorporates a connector, and which is used for connection to an anchor point NOTE Some anchor lanyards are also known as cow’s tailsA multi-purpose area shall be available at suitable location on the lowest topside deck to house the required welfare and emergency accommodation facilities for personnel working on the OSS.The multi-purpose area shall be a single enclosed area with internal divisions to create separate rooms to accommodate the different functions and facilities required in suitable spaces for the intended uses and applications.The multi-purpose area shall be designed as a manned area. The multi-purpose area shall contain the following functions and facilities:• Floor space for emergency overnight shelter for POBUse of chemicals and articles in design and operation shall comply with Company technical requirements provided in TR1668 Prohibited and Restricted Chemicals /16/.• Storage facility for emergency, escape and rescue equipment• Separate area to facilitate toilets with air extraction unitsThe multi-purpose area shall minimum contain the following equipment:• Personal lockers and bench area for POB• Table with chairs for POB, including sockets for personal laptops• Pantry including: (with timer on electric appliances): o Microwave o Electric kettle o Facility for hand wash o Cupboard o Trash can• Storage facilities for emergency, escape and rescue equipment, including: o Two (2) incinerated toilets o Emergency shower o Sleeping bags, sleeping pads, dry provision, and bottled water for POB for 5 days o Other miscellaneous safety and first aid equipment ref 3.3.1• Two (2) foldable bedsCommunication facilities, such as VHF station, IP telephony, fixed UHF-radio• Slave Fire Detection (FiDe) and Fire fighting (FiFi) control panel• One Electrical System Interface (ESI) SCADA workstation, one Wind Turbine Generator (WTG) SCADA workstation and one engineering workstationThe layout design of the multi-purpose area shall consider the locker/changing room area as a wet area designated as the main entrance separated from the other rooms with internal doors. This is to split the area into a dirty and a clean zone and to function as an “airlock” for the office/welfare area to external environments.The locker/changing room area shall be designated as the primary muster area.Exhaust outlets and vents containing hazardous components shall be designed to prevent contamination into air inlets and work areas.A permanently installed cabinet shall be located at suitable location outdoors to enable temporary storage of hazardous chemicals.Noise and vibration levels shall comply with relevant Polish authority requirements and the Company upper area noise limits are given in Table 1 (the stricter requirement prevails).Areas with noise levels exceeding 80 dB(A) or 124 dB(C) peak shall be marked with warning signs.Working areas, ladders, stairs, and access routes shall be placed or protected such that contact with piping and equipment surfaces with a temperature above +60°C or below -10°C is avoided.Two operating modes for lighting shall be provided: Manned and unmanned. Reference is made to chapter 6.11.The work area light intensity shall be adequate for the general purpose of the location and type of activity when the platform is manned. Illumination shall comply with relevant Polish authority requirements and the Company illumination levels given in Table 2 (the stricter requirement prevails).Suitable design measures need to be implemented to prevent or reduce unnecessary light emissions. Table 2. Company minimum illumination requirements (TR0926)The lighting of areas monitored by closed-circuit television (CCTV) equipment shall be sufficient and ensure efficient operations. The sensitivity and technical specifications of the CCTV equipment shall be considered in the lighting design.Non-ionizing radiation doses shall be kept as low as reasonably practicable. Exposure levels of non-ionizing radiation shall comply with Polish requirements and shall not exceed the “ICNIRP Basic Restrictions and Reference Levels for occupational and general public exposure”.The design should minimize exposure to electromagnetic field (EMF) and areas where levels are above reference levels for general public exposure shall be marked with warning signs.Biologically contaminated waste material (organic waste, medical waste, sewage, drain) shall be contained and kept in closed systems.For technical safety requirements and description of need and role of safety barriers it is referred to the safety strategy for offshore substation MFW & MFW , ref. /17/.A design accidental load report shall be based on risk analysis and guidance provided below in Table 3. Additional accidental loads shall be identified by risk assessment.Availability and reliability requirements for components used as part of instrumented safety barriers shall be as follows: Predefined minimum performance level (SIL) for the components, part of instrumented safety barriers, shall be as provided in Table 1, when used to protect against severe safety, environment and/or business loss/asset consequence. The requirements are limited to the components, and not to the entire functions. All components used in the instrumented safety barriers defined in Table 1 shall be certified in accordance with IEC 61508 or “proven in use” as described in IEC 61508-2, clause 7.4.10. For machinery safety functions shall be compliant with relevant IEC standards e.g. IEC 62061 "Safety of machinery: Functional safety of electrical, electronic and programmable electronic control systems". The applicable safety system, or affected parts of it, shall be designed to fail-to-safe principle, whereby the system goes to a predefined safe state in the event of detectable malfunction. If it is not feasible to implement a fail-to-safe principle, an equivalent level of safety shall be achieved by redundancy and/or diagnostics and fault alarm to the control room. The probability of single defects / failures causing inadvertent trip actions shall be as low as reasonably practicable All barriers or parts thereof, shall be protected against environmental conditions that may compromise their safety functions, e.g. ice, snow, sand, water, etcTable 1: SIL guidance for typical components used as instrumented safety barriers relevant for offshore windRequirements for evacuation systems are provided in safety strategy /17/.An escape chute solution and liferaft(s) shall be included on two separate locations of the platform to maximize availability. See Figure 1. Example of escape chute arrangement for example used on another installation./ Figure 1. Example of escape chute arrangementSee further requirements to safety and first aid equipment in safety strategy /17/.A helicopter winching area shall be provided on the top deck, properly marked with text, symbols and aviation lighting according to relevant Polish rules and regulations. There shall be no obstructions such as antennas, masts or other equipment preventing helicopter access above the winching area. Polish regulations shall be followed, and this is assumed to be a maximum helicopter rotor diameter size of 17.2 m (Sikorsky S92 with D- value = 20.9 m).The boat landing ladder(s) shall also be utilized as escape to sea ladder(s). Minimum one escape to sea ladder shall be available in all operational modes, including during temporary phases with flotel/JUR operation.Miscellaneous safety equipment types, locations and quantities shall as a minimum be selected with respect to the following requirements and be approved by Company:Safety equipment shall be of an appropriate rating designed for offshore use and shall be stored on the OSS in line with manufacturer instructions.Outdoor located safety equipment shall be climate protected if required.Safety showers shall be of portable type, selcontained with respect to water and pressure, and stored in frost protected area.ID, signage, marking and illumination of signage/markings shall be in accordance with Polish laws, rules and regulations. Text on safety signs shall be dual language, Polish and English language.See further requirements to safety signs and markings in safety strategy /17/. For all electrical breakers arc flash levels need to be clearly stated next to the breaker.Reference to appendix E for environmental requirements. To further emphasize: Air Emissions Air emissions shall comply with relevant EU and Polish rules and regulations.Diesel generator air emissions shall comply with Polish regulations. The diesel generator shall meet the emission standard for emergency use.Discharge from drain system from areas with potential hazardous leaks sources shall comply with Polish regulations. Effluent to sea shall be controlled and monitored such that the oil content without dilution is less than 15 parts per million (ppm).Drain systems and/or containment shall be provided to contain and collect spills and leaks in all areas that have a source of flammable or environmentally hazardous liquid.Drain system with direct discharge to sea shall be provided for other external areas for drainage of rainwater.Areas provided with drain connections with direct discharge to sea, areas provided with oily water drain connections and areas provided without drain connections shall be clearly documented in relevant documentation.Drain systems shall be segregated. Drains which can be expected to only receive rainwater shall be segregated from drains where flammable or environmentally hazardous liquid can be expected. Drain from areas with flammable or environmentally hazardous liquids shall be routed via an oil-water separator.Drain systems shall be designed such that it is not possible to transfer liquid from one drain area to another (e.g. back-flow from A system to B system).The drain systems shall maintain operability in cold conditions and not become damaged in case of freezing during a long power outage. Use of heat tracing shall be used where there is a risk of standing water and to ensure availability of valves in the drain systems. Heat tracing shall be of self-limiting/self-regulating type, designed and installed per IEC 61892-1:2019 and TR3023.Distribution: Classification: Internal Expiry date: Status FinalTitle: Offshore Substation (OSS) Topside Technical Specification Contract no.: Project: Document no: C256-EQ-Z-SP-00009Type of work Average lux Outdoor non work 20 Simple orientation, temporary visits 50 Occasional visual tasks only 100 Medium precision work 200 Precision work 500Area / activity Area noise limit, dB(A) (Incl. structural induced noise) Unmanned machinery rooms where stays involve brief inspections only 110 Main equipment rooms & utility areas 85 Outdoor muster & lay down areas 75 Light industry work, workshop 65 Administrative spaces, multipurpose area, 55 Location: At a distance of 1 m from each item of plant or its acoustic enclosure and at 1.2 m above the floor level, or elevated platform.Design accidental load Guidance Fire loads on loadbearing structures Fire load scenarios for high voltage (HV) electrical equipment shall be based on input from supplier. See safety strategy /17/, for guidance regarding oil filled transformers. Explosion The structure shall be designed for relevant explosion loads. See safety strategy /17/, for guidance regarding oil filled transformers. Dropped object loads All structures in lifting routes and defined laydown areas shall be designed for dropped objects. These loads must reflect planned material handling at or above the platform, if lifting restrictions are not implemented. Deck structures above transformers, generator and diesel tank shall be designed to withstand dropped objects. Design impact load to be determined based on material handling study. Swinging objects loads Swinging load protection must be implemented as required to prevent impact to critical equipment and critical damage to load bearing structures. This is relevant in all foreseeable lifting zones from cranes on the OSS and use of SOV gangway and, if equipped, gangway associated crane. For structures and equipment, the design load for swinging object loads shall be based on material handling study.Performance standard Component SIL Functional boundaries / comments Fire damper SIL 2 PS 2 – Natural ventilation and HVAC When used to prevent ingress or spreading of gas or smoke SF6 gas detector SIL 2 When used for protection against asphyxiation. PS 3 – leak detection SIL 2 Flammable fluid gas detection (HC, etc.) H2 detector SIL 2 When installed and used in battery or hypochlorite rooms to prevent explosive atmosphere SIL 1 Shut off valves (flammable/toxic medium) The SIL requirement applies only to valves protecting against severe safety, environment and/or asset consequences or preventing escalation, and includes: - Solenoid - Actuator - Valve body PS 4 – Emergency shutdown (ESD)SIL 1 ESD push buttons/switch Overall SIL 2 Safety logic solver (excluding IEDs) Requirement applies to input & output cards, and CPU. System safety manual shall provide guidance to applications and application program development. Smoke detector SIL 2 PS 7 – Fire detection Flame detector SIL 2 Heat detector SIL 2 Multi detectors SIL 2 SIL 2 PS 9: Active fire protection Nitrogen release valve (water mist) SIL 2 Pressure regulating valve (water mist) SIL 2 Water mist zone valves (incl. solenoid) SIL 2 Inergen release valve SIL 2 Foam release valve