ENGINEERING SPECIFICATION

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Transcription:

1 (32) ENGINEERING SPECIFICATION ES16 Fire & Safety - Detection, Prevention & Protection

2 (32) Index 1 GENERAL...5 1.1 Abbreviations...5 1.2 Application...5 1.3 Safe location...6 1.3.1 Vent to safe location...6 1.3.2 Operation for emergency equipment at safe location (API521)...6 1.3.3 Fresh air to buildings or furnaces at safe location...6 2 EMERGENCY ALARM, FIRE AND GAS DETECTION SYSTEMS...6 2.1 Buildings...6 2.2 Process and offsite areas...7 2.2.1 Site emergency alarm...7 2.2.2 General:...7 2.2.3 Fire detection system:...7 2.2.4 Flammable gas detection...8 2.2.5 Toxic gas detection...8 2.2.6 Atmospheric Tanks...8 2.2.7 Pressurised Tanks...9 3 ISOLATION AND DEPRESSURING OF PROCESS EQUIPMENT...9 3.1 Isolation of process vessels at emergencies General...9 3.2 Emptying of liquid inventory...9 3.3 Depressuring of process vessels...9 3.4 Isolation of vessels by Remote Operated Emergency Isolation Valves...10 3.4.1 General:...10 3.4.2 EIV on vessel not directly connected to a pump or compressor...11 3.4.3 EIV on pump system...11 3.4.4 EIV on compressor system...12 3.5 Isolation for maintenance....12 4 FIRE WATER SYSTEM...12 4.1 General...12 4.1.1 Fire safety assessment...12

3 (32) 4.1.2 Material used for fire water systems above ground (pipes, monitors, spray systems):...12 4.1.3 Fire water demand calculation...13 4.1.4 Fire water supply, storage and pumping...13 4.1.5 Fire water ring main (NFPA 24)...14 4.2 Fire hydrants (NFPA 24)...15 4.3 Water spray systems (NFPA 15)...15 4.4 Monitors (NFPA 24)...16 4.5 Portable extinguishers (NFPA 10 and EN 3)...16 4.6 Steam lances...17 4.7 Steam rings...17 4.8 Dry risers...17 5 FIRE PROTECTION OF SPECIFIC EQUIPMENT...17 5.1 Buildings (BBR20, AFS 2009:2)...17 5.2 LPG containing vessels (NFPA 15)...17 5.3 Pumps (NFPA 15)...18 5.4 Compressors (NFPA 15)...18 5.5 Heaters (NFPA 86)...18 5.6 Tanks and bunds (NFPA 11 / EN 13565)...19 5.6.1 Tank bunds...19 5.7 Jetties...19 5.7.1 Fire Water main (NFPA 24)...19 5.7.2 Fire Pumps (NFPA 20)...20 5.7.3 Fire Hydrants (NFPA 24 / 307)...20 5.7.4 Monitors Master Streams (NFPA 24)...20 6 PASSIVE PROTECTION - FIRE PROOFING...20 6.1 Steel structures...20 6.2 Electrical-& instrument cables...20 7 References...20 8 REVISIONS...21 9 Audit...21 10 Appendix 1 Plant layout and spacing...22 10.1 Application...22 10.2 Basic design intentions...22

4 (32) 10.3 Overall Plant Layout...23 10.4 On site - Process Units...24 10.4.1 Process hazards...25 10.4.2 Intra-Unit Spacing...25 10.5 Offsite - Tank Farms...26 10.5.1 Atmospheric Storage Tanks...27 10.5.2 Pressurized and Refrigerated Storage Tanks Spheres and spheroids:...27 10.5.3 Drums and bullets:...27 10.5.4 Refrigerated dome roof tanks:...28 10.6 Utilities...28 10.7 Control Rooms...28 10.8 Services...28 10.9 Loading and Unloading...28 10.10 Table 1 - minimum inter-unit spacing...29 10.11 Table 2 general recommendations for spacing aboveground storage tanks...30 10.12 Table 3 - general recommendations for spacing aboveground storage tanks...31 10.13 Revision of plant layout and spacing...32 10.14 Audit of plant layout and spacing...32

5 (32) 1 GENERAL 1.1 Abbreviations NFPA codes National Fire Protection Agency EN standards European standards RP&G Recommended Practices and Guides ES Engineering specification RP Recommended Practice BP Best Practice ALARP As Low As Reasonably Practicable API American Petroleum Institute ATEX ATmosphères EXplosibles (2014/34/EU) PPE Personal Protective Equipment LEL Lower Explosive Limit QRA Quantitative Risk Assessment HVAC Heating, ventilation and air conditioning GHAB Göteborgs Hamn AB LPG Liquid Petroleum Gas LOPC Loss Of Primary Containment EIV Emergency Isolation Valve DCS distributed control system GRP Glass-fiber Reinforced Plastic BBR Boverkets byggregler (Swedish legislation) AFS Arbetsmiljöverkets författningssamling (Swedish legislation) 1.2 Application This NFPA Codes, EN Standards, Recommended Practices and Guides (latest revision) shall be applied when installing new process units or new process equipment at Preemraff. ES lists exceptions and clarifications of these standards and codes and specific requirements that shall be applied for Preemraff. It also serves as a guideline for improving safety at existing units as further defined in Preemraffs long-term plan. When conflicting information s in regulations, codes, standards, RP, BP and ES the most strict demand shall be used. When liquid volumes are mentioned it refers to normal operating level if not stated otherwise. For distillation towers the volumes shall incorporate the liquid on distillation trays above the draw-off tray/outlet pipe to the equipment in question. For all paragraphs in this ES specification the following apply: Proposed systems and solutions shall be discussed and final approved by Preemraff.

6 (32) If exceptions from this ES is required, exceptions is regulated in NO201 Tekniska specifikationer, if not specified in specific paragraph. In cases where this standard use the word shall the equipment mentioned is compulsory. Risks shall be reduced to ALARP (As Low As Reasonably Practicable) when applicable. Note that general specifications is described in section 1-4. Section 5 describes specific equipment and products. That means that section 5 shall always be studied and the highest demand applies. 1.3 Safe location There are three different types of safe location. 1.3.1 Vent to safe location Outlet from compressor vent, other vents, relief valve or similar: Shall be at a place where there are no ignition sources and not possible to expose personnel for a fire exceeding 6.31 kw/m 2. Outlet shall be included in ATEX classification document, for more information see SA405 Uppfyllande av ATEX-direktivet. 1.3.2 Operation for emergency equipment at safe location (API521) Where safe location is mentioned it is to be seen as a place that not will be exposed to thermal radiation levels over 4.73 kw/m 2 according to fire safety assessment. If the equipment is meant to be activate by fire responder with full PPE the maximum level shall be 6.31 kw/m 2. 1.3.3 Fresh air to buildings or furnaces at safe location Fresh air intake to buildings and furnace shall be located above or otherwise outside ATEX classified area (see also gas detection in fresh air intake in this document). 2 EMERGENCY ALARM, FIRE AND GAS DETECTION SYSTEMS 2.1 Buildings All buildings shall have fire detection systems connected to Preemraff fire detection system and, when applicable, local evacuation alarms. For temporary buildings a risk assessment can allow lower demands. For normally unmanned rooms where critical instrument, electrical, battery and/or computer equipment is situated high sensitive smoke detection shall be evaluated.

7 (32) If flammable/toxic/inert gas is handled or anticipated inside buildings a gas detection system shall be installed (e.g. LEL/toxic/O 2 ). System alarms shall be connected to and integrated with the process control/alarm system for the process unit concerned and, when applicable, local evacuation alarms. In addition flammable and toxic (H 2 S) gas detectors shall be installed in the fresh air intake of control room and electric / instrument substations air conditioning. The need for smoke detectors shall also be evaluated. For other manned buildings flammable/toxic (H 2 S)/smoke detectors shall be evaluated, the site QRA can be used as guidance. Mechanical ventilation (HVAC or similar) shall automatically stop upon alarm. 2.2 Process and offsite areas 2.2.1 Site emergency alarm An alarm system shall be installed which can be heard and/or visible throughout the risk area (including manned buildings) in case of an emergency. For new units or modification of existing units it must be evaluated if existing system is sufficient or extension of existing system is required. The system shall be possible to activate from a manned control room and in accordance to ES11-40 Instrumentation and Control. Exception is harbor areas with other responsible authority e.g. GHAB. 2.2.2 General: Common for all systems described below is that, alarms shall be connected to the fire and gas detection system. For details see ES 11-40 Instrumentation and Control. It shall also be possible to activate remote/automatic systems (e.g. deluge and/or evacuation alarm) from activated alarm. To be able to optimize the number analyzers/detectors and where to position them in site a study over the area shall be performed in large projects and should be considered in all other projects (preferably a software simulation program shall be used). The aim is to detect a flammable or toxic gas cloud and a fire flame within acceptable limits. The following can be used for guidance of required capability of the detector systems used: Fire detections: A pool fire (N-heptane) with 100 kw radiant heat output. Flammable gas: A cloud size (sphere) of 10 m in diameter. Toxic gas (H2S): A cloud size (sphere) of 8 m in diameter. 2.2.3 Fire detection system: Fire detection system shall be installed in field in the following areas:

8 (32) Hydrocarbon and hydrogen centrifugal compressors areas. Pumps handling Hydrocarbons operating at temperature above auto ignition or 250 o C. Pumps handling LPG. For other fire hazardous areas (e.g. heat exchangers, process heaters) or remote pump stations (e.g. gasoline blender, cavern) fire detections shall be evaluated. If indoors local fire alarms is applicable in the same way as for manned buildings, the alarm shall be heard and/or visible from all locations. Even less fire hazardous, but expensive equipment (e.g. single sophisticated pumps) or pumps having serious consequence to plant operations, shall be evaluated. 2.2.4 Flammable gas detection Flammable gas detection system shall cover the process and offsite area where it is not unlikely that a leakage of flammable gas can occur (e.g. vessels, heat exchangers, pumps handling hydrocarbons at elevated temperature or pressure). In addition flammable gas detection shall be installed in the following areas: Hydrocarbon or hydrogen gas compressors areas. Pumps handling LPG. To achieve enough risk reduction it is often necessary to combine different types of gas detectors (e.g. Line of Sight, point and sonic detectors). 2.2.5 Toxic gas detection Toxic gas detection system shall be installed strategically in the process units, where the toxic gas can be present. Guideline regarding H 2 S detectors at potential leak points: Process streams containing H 2 S in concentrations 100-1 000 ppm H 2 S detectors shall be evaluated. Process streams containing H 2 S in concentrations over 1 000 ppm H 2 S detectors shall be installed. 2.2.6 Atmospheric Tanks Open floating roof tanks shall have fire detection system in the seal area type Protectowire or similar. Tanks with internal floating roof shall have UV-fire detection system (or similar) in the space between roofs.

9 (32) Tanks containing hydrocarbons with design storage temperature higher than 5 C below flashpoint shall have flammable gas detection system in the tank bunds. The need for fire detections in all tank bunds shall be evaluated. 2.2.7 Pressurised Tanks Pressurised tanks to have fire and gas detection system covering tank equipment e.g. safety valves, tank connections and manway. 3 ISOLATION AND DEPRESSURING OF PROCESS EQUIPMENT 3.1 Isolation of process vessels at emergencies General In case of leakage (LOPC) or other emergencies, it shall be possible to isolate, empty and depressurise process vessels containing hydrocarbons. (Process vessels include towers, reactors, heaters, heat exchangers etc.). The purpose is to minimise the leakage or to avoid loss of containment. The process design of each individual process vessel shall take this requirement into consideration. The resulting strategy and operating instructions shall be documented as part of the operating manual. Isolation can be done either for an individual piece of equipment or a system of several items e.g. heat exchangers. 3.2 Emptying of liquid inventory Emptying of liquid in process vessels must be possible by pumps or by the operating pressure. 3.3 Depressuring of process vessels Depressurisation can be initiated manually by the operator or automatically. Events that may lead to severe consequences in a relatively short timeframe require remote high rate emergency depressuring. Examples on applications: LPG vessels above 4 m 3 liquid volume, large volumes of flammable gas and high pressure and also reactor circuits with possible runaway reactions. High rate emergency depressuring typically meets the following criteria: depressure the equipment to 7 barg or 50 % of design pressure, whichever is lower, within 15 min. Alternative high rate emergency depressuring criteria (more stringent or more liberal) shall be supported by analysis. The above criteria do not imply that the depressuring stops after 15 min.

10 (32) Special considerations to prevent spurious trips are required. The depressuring system shall be operable during fire conditions. 3.4 Isolation of vessels by Remote Operated Emergency Isolation Valves 3.4.1 General: All EIV valves shall be equipped to allow full or partial stroke test during operation. Systems containing particles or high viscous material (increased risk for valve not able to give a tight shut off) systems allowing full stroke test is preferred. If a vessel not falls within the limits below evaluations shall be done to verify if the volume in systems upstream the vessel (e.g. pipe, exchangers, distillation tower) can be considered to be large enough to justify an EIV. All EIV shall have three ways of controlling the EIV. One local, one at safe location and one in the DCS system. Maneuver points at safe location shall preferably be grouped together. If a system is exposed to unusually many planned changes in pressure and/or temperature (compared to normal operation which means operating for 1-6 years without any major changes) or systems where process flanges are opened (e.g. filters, dryers or other systems which is operated/changed on a regular bases) special attentions can be needed. These systems can in some cases be seen as hazardous enough to have an EIV even if the volume or material criteria below are not met. Where the text below calls for evaluation of an EIV the hazop meeting report shall have a note clearly stating the recommendation from the hazop team regarding EIV or not. If the hazop meeting comes to the conclusion that a system (that falls within the criteria below) don`t need an EIV this shall be clearly noted in the hazop report with an explanation of the facts that the group based its decision on. The decision should be confirmed by Preemraff. For fired heaters se also ES 09. Normally EIV shall have a fail close action. If there is a need for other fail action this shall be verified by the hazop team and clearly noted in the hazop protocol. If the hazop meeting comes to the conclusion that the EIV is expected to be operable during a fire scenario (and not direct go to a fail-safe position) EIV and power (electric and air) supply shall be fire proofed.

11 (32) If the EIV is positioned in locations where high thermal radiations are expected during a fire scenario the valve shall be fire safe. 3.4.2 EIV on vessel not directly connected to a pump or compressor EIV shall be provided on process vessel with a liquid volume of 25 m 3 or more handling: LPG (or lighter) Liquid at temperature above auto ignition temperature or above 250 o C Hydrocarbons handled at temperature above flash point and operating system pressure above 17 barg. Systems handling acute toxic material (e.g. H 2 S, see also 2.2.5) shall be evaluated if EIV shall be used regardless of the volume. If there is a remote operated control valve in the above systems which is positioned in a suitable place the hazop meeting shall decide if it can be used instead of an EIV. If so, this shall be clearly noted in the hazop protocol. 3.4.3 EIV on pump system EIV shall be provided on process vessel with a liquid volume of 4 m 3 or more handling: LPG (or lighter) Liquid at temperature above auto ignition temperature or above 250 o C EIV shall be provided on process vessel with a liquid volume of 15 m 3 or more handling: Hydrocarbons handled at temperature above flash point and operating system pressure above 17 barg. Systems handling acute toxic material (e.g. H 2 S, see also 2.2.5) shall be evaluated if EIV shall be used regardless of the volume. EIV shall be provided on process vessel with a liquid volume of 30 m 3 or more handling: Other hydrocarbon (than mentioned above) EIV (as mentioned above) shall always be on suction side of the pump. Normally the EIV is positioned as close to the suction vessel as possible. On pump systems (if there are two or more pumps) handling liquid containing particles or have a high viscosity (increased risk for valve not able to give a tight shut off), evaluation shall be done if the EIV shall be placed on the separate suction line to each pump to be able to do a full stroke test on the EIV. If there are filters on the suction side of the pump evaluation shall be done to verify if the EIV should be placed upstream filters.

12 (32) The discharge side of the pump shall always have checkvalve/s. If the pumped liquid contains particles or have a high viscosity (increased risk for valve not able to give a tight shut off), evaluation shall be done if the system shall have an EIV. This will be of special interest if the delta pressure over the pump (when stopped) is high. 3.4.4 EIV on compressor system The discharge side of the compressor shall always have checkvalve/s. On all centrifugal compressor system handling flammable hydrocarbon or hydrogen rich gases evaluations shall be made if EIV shall be installed on the suction and discharge side of the compressor. Systems handling acute toxic material (e.g. H 2 S, see also 2.2.5) shall be evaluated if EIV shall be used regardless of the volume. 3.5 Isolation for maintenance. For details regarding valves and blinds in process equipment, see ES 08. 4 FIRE WATER SYSTEM 4.1 General 4.1.1 Fire safety assessment Definition of a fire area: Fire area is normally a process unit (or parts of it) including minimum 15 m of open area to the closest process equipment of the adjacent areas. Used for dimensioning of passive fire protection, for more information see ES19. Pool fire area: Pool fire area at Preemraff normally defined as 250 m 2 (sources mention areas between 232 m 2, 2 500 sqft, and 300 m 2 ). Used for relief valve calculations, flare calculation and water sprinkler systems. 4.1.2 Material used for fire water systems above ground (pipes, monitors, spray systems): Firewater pipelines likely to handle salt water the preferred material is glass-fiber reinforced plastic (GRP). Hot dipped galvanized steel could be an alternative. Firewater pipelines unlikely to handle salt water (process areas normally connected to permanent sprinkler or monitor) the preferred material is hot dipped galvanized steel or

13 (32) stainless steel (316L or better). Where risk of clogging equipment (e.g. spray nozzle) a strainer shall be mounted and it shall withstand full system differential pressure. Spray system nozzle to be stainless steel (316L or better) or brass. Spray system and monitors shall be possible to flush, test and drain in a proper way. 4.1.3 Fire water demand calculation As a base for requirement of active fire protection systems there shall be a fire safety assessment based on a 50 mm circular hole in equipment. The quantity of water required for control and extinguish one major fire shall be based on the largest credible fire scenario occurring through the Process, Storage and Jetty areas. Normally only one fire scenario at a time shall be considered. Fire safety assessment shall consider to include more than one simultaneously fire case for large expansions with project costs exceeding 300 MSEK. 4.1.4 Fire water supply, storage and pumping Fire water shall be stored in a dedicated water storage tank for firefighting purposes. The level in the tank shall always be high enough to give a minimum of two hour at maximum flow rate without any refilling. The position of the tank shall be minimum 50 m away from fire area. To be able to do maintenance on the fire water tank alternative supply to fire water mains shall be available. The main fire water pumps shall be able to pump the maximum flow (as stated above). A minimum of one standby pump shall be available (with the same capacity, or higher, as the highest capacity main pump) One of the main pumps shall be driven by an electric motor while the other ones of the main pumps and stand by pump shall be diesel driven. Another alternative is that the standby diesel can handle the maximum case if all main pumps are electric. (When diesel driven pumps are used there shall be a system for fire detection and fire extinguishing for these pump system). Fire water pumps shall be installed in a location which is considered to be safe from the effects of fire and clouds of flammable vapor, and from collision damage by vehicles. The pumps should be located as close as possible to the fire water storage or alternative water source. The fire water pumps rated pressure shall be based on a minimum pressure of 10 barg at the most remote end of fire main with the highest water flow demand. If the required pump capacity exceeds 1 000 m3/h, two or more smaller pumps shall be installed.

14 (32) One out of suggested alternatives below shall be used as a minimum: Electric 1 Electric 2 Diesel 1 Diesel 2 Alternative 1 100% 100% 100% Alternative 2 60% 60% 60% 60% Alternative 3 60% 60% 100% Two fire water jockey pumps, electric motor driven, one in normal operation one in standby, shall be provided to keep system pressure against leakage and allow automatic starting of fire water pumps in sequence in case of fire water demand higher than the normal pumps capacity. Alternatives to jockey pump is controlled/regulated main pumps in normal operation. The jockey/main in normal operation shall have typical capacity to compensate for leakage plus plant service water specified by Preemraff. The pumps shall maintain a minimum pressure of 3-4 barg in the fire water distribution system. The pumps and accessories shall be designed according to NFPA 20 requirements. 4.1.5 Fire water ring main (NFPA 24) Firewater ring main shall be a 12 (minimum) underground system. Laterals normally also shall be 12, smaller size can be accepted depending of number of hydrants and/or sprinkling systems connected. The main ring shall be designed in order to have a minimum pressure of 10 barg at all areas and at farthest outlet point under the fire water demand required by the relevant fire scenario, with the maximum flow velocity in the system not exceeding specifications in ES08. A surge analysis of the firewater distribution system shall be performed and, where required, surge protection devices shall be provided. The fire water piping shall be installed as a "looped" system, with strategically located, isolation valves. Isolation valves to be full bore valves and it shall be possible to verify valve position (open or closed). The installation of these valves is based on the following criteria: When fire water pipes serving hydrants, monitors, or wall hose reels are taken out of service for maintenance alternative ways to supply water by hoses shall be available. Hose length shall not be more than 100 m. The remaining part of the local fire water ring shall be able to supply design flow rates at the design pressure at all times. No more than 4 equipment of hydrants and monitors shall be out of service at any time as a result of maintenance on the firewater mains.

15 (32) The fire water piping on minimum two sides of process units shall remain in service at all times. 4.2 Fire hydrants (NFPA 24) Fire hydrants shall be constructed in accordance to Std HB 1002-49 BP01 in process area and BP03 in off plot areas (deviations to be approved by Preemraff) and connected to firemain or lateral headers in accordance to Std HB 1002-48 (LYR) or Std HB xxxx-xx (GOR). Where water spray protection of process equipment from fire hydrant is needed (according to the fire safety assessment) water monitor shall be fitted. If foam protection of process equipment from fire hydrant is needed (according to the fire safety assessment), appropriate foam monitor system shall be fitted. Fire hydrants shall be located along roadside maximum 50 meters apart on site and some parts of off-site (e.g. LPG storage, jettys, pump stations, blending stations). For the rest of offsite 100 m shall apply. For occupied buildings BBR applies. In the offsite area (mainly around tanks) provision of big hydrants shall be evaluated. These are to be used in connection with a major tank fire for cooling and extinguishing purpose. Hydrants shall be readily accessible from roads and be located in such a way that possible damage by road traffic will be minimised. They shall be provided with a guard post. The location should not be less than 1.5 m from the curb of the road, and at least 10 m from road crossings, sharp road curves, and buildings or other structures. Each hydrant shall be provided with a hard-paved grade or grating. All hydrants in and around a process plant shall be of the type suitable to mount stationary monitors, see standard drawing. This shall also be considered for other specific locations as directed by the fire safety assessment. 4.3 Water spray systems (NFPA 15) All process equipment (e.g. vessel, towers, pumps, pipes) that not can be sufficiently protected by a permanent water monitor shall be evaluated if there are needs for a permanent water spray system up to a height of 11 m above ground (or 11 m above any platforms that can contain a poolfire). For passive fire protection on process equipment and supporting structures, see ES19. Water spray systems shall be in accordance to Std HB 1002-47.

16 (32) Systems shall be possible to operate from three separate places: Manually at valve pit, local remote control at safe location and in DCS system. System to be fail open in case of malfunction of air or electrical signals to the system. As general rule equipment likely to be exposed to a heat radiation level between 12 kw/m 2 and 32 kw/m 2 can be covered by permanent monitors or mobile monitors. Heat radiation level above 32 kw/m 2 normally will need a permanent water spray system to be effective. Design fire water rates for general cooling of structure and pipe racks are to be a minimum of 2 l/m 2 /min. If process equipment (e.g. vessels, towers) are effected the minimum rate will be 10 l/m 2 /min. If the fire safety assessment gives higher rates that will apply. 4.4 Monitors (NFPA 24) Water monitors shall have a capacity of minimum 1 900 litres /min at 7 barg. Foam and/or water monitors either shall be detachable or firmly mounted monitors. For detailed information se Std HB 1002-49 sheet 2. Where monitors at grade (on top of hydrants) can`t sufficiently cover the fire area, elevated monitors or monitors inside process areas at optimized positions shall be evaluated. The aim for critical equipment is two separate monitors to cover the equipment. The elevated monitors shall be possible to control (elevation, rotation and nozzle setting) at elevated position. Feed valve to the elevated monitor shall be operable from grade (at hydrant, at safe location and from control room) and pipe to monitor shall be able to drain free of water after use or test. Design fire water rates for general cooling of structure and pipe racks are to be a minimum of 2 l/m 2 /min. If process equipment (e.g. vessels, towers) are effected the minimum rate will be 10 l/m 2 /min. If the fire safety assessment gives higher flowrates those will apply. For all monitors an assessment to be done if foam injection, non-aspirating, shall be possible, this also applies for truck/rail loading stations. 4.5 Portable extinguishers (NFPA 10 and EN 3) Portable extinguishers type 233 BC (hydrocarbon fire) shall be positioned close to equipment where risk for fire exists, 12 kg to be selected (exceptions to be approved by Preem). Generally a maximum distance between extinguishers shall not exceed 25 meters. For visibility and ease of handling preferred location is alongside foundation of pipe rack superstructures. On elevated structures extinguisher shall be positioned at entrance/ leaving points (eg. at stairs). Signs indicating extinguisher position and extinguisher shall be weather protected.

17 (32) Larger portable pressurized (e.g.50 kg powder) extinguishers with a minimum hose length of 5 meters and having similar efficiency of the powder as type mentioned above, shall be positioned in the centre line of a process finger. Distance between extinguishers depends upon risk present and does normally not exceed 50 meters. Signs indicating extinguisher position and extinguisher shall be weather protected. 4.6 Steam lances Steam lances are used for extinguishing fires as well as preventing fires to occur. To feed steam lances utility stations according to Preemraff ES-08 shall be arranged on site. 4.7 Steam rings Heavy flanges in high-pressure/high-temperature service (e.g. reactors, heat exchangers) shall be evaluated for installation of fixed steam rings. Systems containing hydrogen with a flange size 6 and larger shall be specially checked. Supply of steam shall be arranged by a stationary installation. Operation of shut off valves for steam rings shall be local from a safe distance (minimum 15 m away) or calculated safe location. 4.8 Dry risers Dry risers are not a part of firefighting systems. They are primarily used for maintenance activities but can be used supplying firewater for protection during hot work. Dry risers shall be installed on superstructures with higher elevation than 8 meters. Typical arrangement of dry riser is shown in dwg. HC-25195/0-Z08 sheet 001. 5 FIRE PROTECTION OF SPECIFIC EQUIPMENT 5.1 Buildings (BBR20, AFS 2009:2) Fire extinguishing equipment and escape philosofy shall follow regulations in BBR and AFS. Computer/instrumental and switchgear/electrical rooms shall be evaluated for automatic extinguishing system, e.g. CO 2, Argonite or water. 5.2 LPG containing vessels (NFPA 15) LPG vessels (within fire areas) with a normal operating volume exceeding 4 m 3 shall be protected either by fixed water spray system or by passive fire protection. Typical service include storage vessels, feed surge drums, overhead drums, and similar.

18 (32) Water spray capacity shall be not less than 10 l/min/m 2 of vessel surface. The system shall be connected to underground fire water mains in accordance to Preemraff STD HB-1002.47. Systems shall be possible to operate from three separate places: Manually at valve pit, local remote control at safe location and in DCS system. System to be fail open in case of malfunction of air or electrical signals to the system. 5.3 Pumps (NFPA 15) Pumps handling LPG (or lighter) shall have permanent water spray system. Pump handling product above auto ignition temperature or operating temperature above 250 o C shall have a permanent water spray system. Systems shall be possible to operate from three separate places: Manually at valve pit, local remote control at safe location and in DCS system. System to be fail open in case of malfunction of air or electrical signals to the system. A maximum of four pumps to be protected by a single spray system. Water spray capacity shall be minimum 20 l/min/m 2. For pumps an assessment to be done if foam injection, non-aspirating, shall be possible. When foam installed the system shall be designed for at least 15 minutes operation. 5.4 Compressors (NFPA 15) Centrifugal compressors handling hydrocarbon and hydrogen rich gas shall have a fixed water spray system. Systems shall be possible to operate from three separate places: Manually at valve pit, local remote control at safe location and in DCS system. System to be fail open in case of malfunction of air or electrical signals to the system. If the compressor have a separate seal and lube oil system it will be evaluated if water spray system shall incorporate that equipment as well. Water spray density shall be minimum 20 l/min/m 2. 5.5 Heaters (NFPA 86) Demands on snuffing steam is described in ES09 Fired heaters. If heaters use fuel oil for firing, medium foam pouring systems on ground in the burner area shall be evaluated.

19 (32) General protection of a heater area shall be by means of fixed foam or water monitors depending upon heater media. 5.6 Tanks and bunds (NFPA 11 / EN 13565) When differences in the standards above the strictest value applies. When tank is nitrogen blanketed all notes below can be challenged. Semifixed extinguishing foam systems shall be installed on all tanks and be designed to extinguish full tank fire. The fixed piping installation for such systems shall be grouped together to a common connecting point for tanks in the group or existing tank installations. The connection point shall be at safe location in case of a tank fire. For floating roof and tanks with high viscosity and/or temperature foam injection at top shall be installed also consult EN13565/NFPA11 for type of extinguishing system. To be able to cool adjacent tanks during a tank fire an adequate cooling system shall be readily available. It can be by fixed or portable monitors or permanent fixed water spray system. Special care should be taken if tank spacing is closer than recommended in applicable codes. In general 2 l/min/m 2 are required for cooling of the adjacent tank, 40% of tank roof and 25% of tank mantle. 5.6.1 Tank bunds The water mains round tank bunds shall be designed to supply sufficient amount of water for extinguish the fire. The hydrants in this area shall be of sufficient number to give the amount of water needed and shall be positioned in a way that they can be used in case of fire. Except above paragraphs no fixed foam or water spray system are installed for tank bunds. The equipment for extinguishing the fire can be mobile or permanent units. 5.7 Jetties 5.7.1 Fire Water main (NFPA 24) Firewater main supply line shall be 12 (minimum) traced and insulated where installed aboveground. The main supply line shall be designed in order to have a minimum pressure of 10 barg at all areas and at farthest outlet point under the fire water demand required by the relevant fire scenario, with the maximum flow velocity in the system not exceeding specifications

20 (32) in ES08. A surge analysis of the firewater distribution system shall be performed and, where required, surge protection devices shall be provided. The firewater system shall be filled with water during normal operation (standby). Connection point to firewater main supply for each jetty from tug shall be supplied in accordance to Preemraff specifications. 5.7.2 Fire Pumps (NFPA 20) Fire pumps, one in normal operating and one in standby, each one to have pressure and capacity to serve fire-extinguishing equipment installed on a jetty / jetty deck. A third backup system (pump or from process) is required, for more information see section 4.1.4. The main fire water pump shall be able to pump the maximum flow (as stated in 4.1.3). 5.7.3 Fire Hydrants (NFPA 24 / 307) Fire hydrants shall be constructed in accordance to Std HB 1002-49 BP03 and supplied with main valve and drain valve upstream the hydrant. Two hydrants shall be installed on each jetty deck, see also 4.2. 5.7.4 Monitors Master Streams (NFPA 24) Each jetty deck shall be covered by minimum two monitors mounted on jetty deck or on separate towers. All parts of the jetty deck and all equipment shall be protected by at least one monitor, fire study shall verify if vessel (or part of vessel) also shall be protected by Preemraff system. Monitors shall be electric remote controlled foam/ water monitors with a minimum capacity of 3 000 l/min each, fire study shall determine number, capacity, type and position, see also 4.1.3. Remote control system to be approved by Preemraff. Each monitor shall have a fire protection to be able to operate when engulfed in fire, this in accordance with ES19, ES11 and ES12. Remote locations and loading arms can be covered with fixed sprinkler system instead of monitor coverage. 6 PASSIVE PROTECTION - FIRE PROOFING 6.1 Steel structures For reference, see ES-19, Fire proofing. 6.2 Electrical-& instrument cables See ES 11 and ES 12. 7 References BBR20

21 (32) AFS 2009:2 API 521 NFPA 10, 11, 15, 20, 24, 86, 307 ES 08, 09, 11, 11-40, 12, 19 EN 13565 EN 3 8 REVISIONS 2014-12-17 Major revision in areas of concern for VGO project. 2016-06-30 Major revision to include all Preemraff. Jonas Åvall, Bo Karlsson, Ann-Louise Kittendorff, Lars Hansson. 9 Audit Date Position Name 2016-06-30 Safety Specialist GOR Safety Specialist GOR/LYR Fire and Rescue Manager SHM Manager Safety Manager Projects GOR Manager Projects Electrical & Instrumentation LYR Manager Projects Mechanical LYR Jonas Åvall Ann-Louise Kittendorff Lars Hansson Malin Hallin Anna Grunewald-Thoor Thomas Liljeroth Andreas Wising John Erkselius

22 (32) 10 Appendix 1 Plant layout and spacing 10.1 Application The specifications and general design intentions shall be applied for all new equipment s and units installed in all Preemraffs facilities. When the design intentions or separation safety distances cannot be applied due to restrictions in existing or new units alternative equally effective safety measures shall be used (e.g. fire proofing, waterspray or blast hardening). All deviations from this document and the final design shall be approved by Preemraff. The information s and specifications in this document is mainly based on international guidelines. The main info in the document and tables comes from GAPS guideline 2.5.2 (Global Asset Protection Services), and for areas not covered by GAP information,information from PIP (Process Industries Practices) and CCPS (Center for Chemical Process Safety) has been used. In some cases Swedish regulation SÄIFS 2000:2 has been used. Many of these guidelines use other non metric values and the conversion to metric has mainly been made without rounding the values. The main intent of the information and specifications are to minimize the risk and consequence of explosions and fire. By applying this recommendation and the spacing and separation distances the following benefits will be achieved: Less explosion damage. Overpressure created by an explosion decrease rapidly as the distance from the center of the explosion increases. Less fire exposure. Radiation intensity from a fire decreases as the square of the separation distance. Higher dilution of gas clouds or plumes. Gas concentration decreases as the distance from the emission source increases. Easier access to equipment for maintenance, inspection and firefighting purposes. Easier spill and spill fire control in open areas. Lower concentration of values, resulting in a lower property damage loss estimates should a given incident occur. In addition to this document there are other Preemraff Engineering standards that give detailed information of accessibility for e.g. work environment, operation and maintenance. 10.2 Basic design intentions The following areas / statements of possible concerns shall be addressed when determining the layout and the separation required. A risk identification (Preemraff and design contractor), using the list below as a minimum, shall be made to compare the planed unit/equipment to a general unit. If any of the areas / statements below raise concerns of a higher risk than for general units the minimum separations recommendations mentioned in this document might need to be increased : High hazard operations and units Grouped operations Critical operations Number of personnel at risk Potential environmental damage Concentration of property and business interruption values Importance of facility for continuing operations Equipment replacement and installation time Interdependency of facilities Critical customer or supplier relationships and market share concerns Fire and explosion exposures Sources of ignition

23 (32) Corrosive or incompatible materials exposures Vapor cloud explosions - Where large amounts of flammable vapors could be released and a vapor cloud explosion could occur, perform a more detailed hazard analysis and evaluation. If deemed necessary increase the separation distance or design unit and equipment for high loads. Potential to damage of building components and outdoor equipment Maintenance and emergency accessibility Drainage and grade sloping of surrounding land Climatic data with particular attention to prevailing wind directions. Future expansions External exposures including other plants, pipelines and transportation (rail, motor vehicle, aircraft, ship) 10.3 Overall Plant Layout Once a site has been selected,(sometimes with restrictions from actual landscape or other restrictions) arrange layout and spacing to reduce the effect of as many as possible of the following controllable and uncontrollable factors that contribute to the risk: site slope climate, exposure to natural hazards, wind direction and force type of process and process design parameters process equipment design (e.g flammable liquid holdups) ignition sources ( e.g. fired heaters, boilers, flare stacks, or other equipment which may cause ignition) with acceptable separation distance upwind of potential vapor leaks or locating the tank farm downhill of essential units active and passive fire protection design (e.g. fire and safety equipment should be located to maximize accessibility and minimize exposure to fires, explosions, or releases) spill control and proper drainage and separation to control spills and fire spread. E.g. ensuring that flammable vapour generated from one facility will diffuse to a concentration well below the lower explosive level (LEL) before it reaches any other facility or area where source of ignition may exist acceptable thermal radiation levels for pool fires or hydrocarbon fires on adjacent equipment and occupied areas accessibility for normal and foreseeable operations and maintenance activities (e.g lifting operation, vehicle access) safe access for firefighting personnel and emergency shutdown activities safe means of egress for personnel evacuation in the event of an emergency acceptable separations to site boundary and public areas acceptable separations to essential facilities such as fire water, control rooms, emergency power supplies, occupied buildings control logic and automation unloading facilities spare parts supply spare production capacity Use a hazard assessment of each plant operation (the same list as in paragraph 2 can be used) to help establish the layout or orientation of blocks or unit battery limits within the plant. Review the possible loss events and the consequences for each proposal. Select a layout which will minimize the overall risk and consequence for personnel, environment, property damage and related business interruption should an incident occur. Subdivide the overall site into general areas dedicated to process units, utilities, services and offices.

24 (32) Since each area or unit block generally has a rectangular shape, keep the maximum unit size to 90 x 180 m for firefighting purposes. Provide access roadways between blocks to allow each section of the plant to be accessible from at least two directions. Size road widths and clearances to handle large moving equipment and emergency vehicles or to a minimum of 8.5 m, whichever is greater. Table 1 provides minimum inter-unit spacing, which should be increased where a hazard analysis shows that larger separation distances are required. Unfavorable conditions, such as inadequate sloping, poor drainage and critical operations, can increase the exposure between units, thus requiring higher separation distances. All distances between units are measured from battery limits. Battery limits as defined for this document is imaginary lines surrounding a unit. This line is typically box shaped and encloses equipment required for the operation of the unit. Cooling towers, maintenance buildings or other structures not integral to the unit are considered to be independent and should not be included in the battery limits. Figure 1 illustrates a good layout based on the prevailing wind 10.4 On site - Process Units The processing units are generally the most hazardous operations in a plant.

25 (32) Often, fire protection spacing requirements will exceed maintenance accessibility requirements. The relative location of equipment depends on its probable release of flammable materials, its flammable liquid holdup, and its potential to be a source of ignition. The risk of domino effect loss is not neglectiblewithin process units and shall be held to a minimum by applying these recommendations.. NFPA 30 defines flammable liquids as Class I materials, and combustible liquids as Class II and III materials. The classification depends on the flash point and boiling point of the product. For separation process equipment see table 1. 10.4.1 Process hazards Evaluate the process hazards and, depending on the results of such review, classify them in moderate, intermediate, and high hazard groups (the classification is used in some of the separation tables below) Moderate - This category includes processes, operations, or materials having a limited explosion hazard and a moderate fire hazard. This class generally involves endothermic reactions and nonreactive operations, such as distillation, absorption, mixing and blending of flammable liquids. Exothermic reactions with no flammable liquids or gases also fit in this hazard group. Example for refineries : Crude distillation, Visbreaking Intermediate - This category includes processes, operations, or materials having an appreciable explosion hazard and a moderate fire hazard. This class generally involves mildly exothermic reactions. Example for refineries : Alkylation, Hydrogenation, Reforming High - This category includes processes, operations, or materials having a high explosion hazard and moderate to heavy fire hazard. This class involves highly exothermic or potential runaway reactions and high hazard products handling.: Example for refineries :Hydrocracking Hazard Classification of pumps High hazard pumps: AIT pumps - Actual AIT or over 250 C Handle flammable and combustible liquids and operate at pressures above 35 bar LPG and lighter Intermediate hazard pumps: All other pumps handling flammable or combustible liquids. 10.4.2 Intra-Unit Spacing For proper intra-unit layout, include the following principles: Do not group pumps and compressors handling flammable products in one single area And do not locate them under piperacks, air cooled heat exchangers and vessels Orient pump and driver axes perpendicular to piperacks or other equipment to minimize fire exposure in case of a pump seal failure Separate high-pressure charge pumps from any other major process equipment and other pumps by at least 7.5 m Compressors (flammable gas) - To avoid unnecessary exposure, do not locate lube oil tanks and pumps directly under any compressor. Detach heaters and furnaces from the unit or at least locate them at one corner of the unit. (e.g. locate continuous ignition sources upwind of the process units) If increased spacing for very high hazard equipment susceptible to explosions, such as reactors is deemed necessary but not practically possible, - separate them from other areas by blast resistant walls.

26 (32) Keep flammable and combustible liquid products storage to a minimum within the process unit boundaries. Install drums, accumulators or similar vessels with flammable liquid holdups at grade, if possible. The preferred layout of a process unit is a piperack located in the center of the unit with large vessels and reactors located outwards of the central piperack. Place pumps at the outer limits of the process area. Limit the stacking of equipment in process structures to equipment with no fire potential. Slope the ground surface so that liquids drain away from the center of the unit. Do not put drainage trenches under piperacks. Put cables in the ground or at trays in the top tier of the piperacks. 10.5 Offsite - Tank Farms For minimum spacing between tank farms and other unit see table 2. See table 3 for general recommendations for spacing aboveground storage tanks in the oil and chemical industry. The spacing is given as a distance from tank shell to tank shell and is a function of the largest tank diameter. If some adverse conditions cannot be avoided, such as poor fire protection water supply, difficult firefighting, poor accessibility, poor diking or poor drainage, increase the spacing by at least 50%. For proper offsite layout, include the following principles: Provide tanks with proper dikes / tank bunds or drainage to a remote impounding facility. Storage dike / tank bund areas or remote impounding s shall be sized to contain minimum 100% for a single tank and for a group of tanks minimum 75 % of the total volume. To these volumes an extra capacity shall be added to be able to contain the calculated amount of fire water and foam used in case of fire. The sloping inside the dikes / tank bunds or to remote impounding facility shall be of minimum 1 % and take the spill away from the tanks. (Refer to NFPA codes for additional requirements) Do not group or dike /bund different types of tanks and contents (class I-III) together. Locate storage tanks at a lower elevation than other occupancies to prevent liquids or gases from flowing toward equipment or buildings and exposing them. Locate tanks downwind of other areas. Arrange atmospheric storage tanks and pressure vessels in rows not more than two deep and adjacent to a road or accessway for adequate firefighting accessibility. Arrangement of storage tanks shall allow for firefighting from at least two sides. Since piping exposed to ground fires usually fails within 10 or 15 min of initial exposure, locate an absolute minimum amount of piping, valves and flanges within dikes / bunds. Install pumps, valve manifolds, and transfer piping outside dikes / bunds or impounding areas. Where tanks over 80,000 m3 are present, increase minimum distances to 300 m spacing between them. Space tanks so the thermal radiation intensity from an exposing fire is too low to ignite the contents of the adjacent tanks. Tolerances of tanks to thermal radiation can be increased by: - Painting vessels a reflective color (generally white or silver). -Providing a fixed water spray or tank shell cooling system. -Insulating or fireproofing the tank shell.