OISD-STANDARD-118 Third Revision FOR RESTRICTED CIRCULATIONLAYOUTS FOR OIL AND GAS INSTALLATIONS OISD-STANDARD-118 First Revision, July 1995 Second Revision. August 1999 Third Revision. August 2000 Oil Industry Safety Directorate Government of India Ministry of Petroleum & Natural Gas OISD-STANDARD-118 First Revision, July 1995 Second Revision, August 1999 Third Revision. August 2000 FOR RESTRICTED CIRCULATION LAYOUTS FOR OIL AND GAS INSTALLATIONS Prepared By : COMMITTEE ON LAYOUTS OIL INDUSTRY SAFETY DIRECTORATE 2ND FLOOR, “KAILASH” 26, KASTURBA GANDHI MARG NEW DELHI-110 001 NOTE OISD publications are prepared for use in the oil and gas industry under Ministry of Petroleum and Natural Gas. These are the property of Ministry of Petroleum & Natural Gas and shall not be reproduced or copied or loaned or exhibited to others without written consent from OISD. Though every effort has been made to assure the accuracy and reliability of the data contained in these documents, OISD hereby expressly disclaims any liability or responsibility for loss or damage resulting from their use. These documents are intended only to supplement and not to replace the prevailing statutory requirements. Note1 in superscript indicates the modification/changes/ addition based on the amendments approved in the 17th Safety Council meeting held in July, 1999. Note 2 in superscript indicates the modification/changes/addition based on the amendments approved in the 18th Safety Council meeting held in August,2000. "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines." Standardisation in design philosophies and operating and maintenance practices at a national level was hardly in existence. As such various practices have been in vogue because of collaboration/association with different foreign companies and governments. “Kailash” 26. Suggestions from industry members may be addressed to: The Coordinator Committee on Layouts Oil Industry Safety Directorate 2nd Floor.FOREWORD The Oil Industry in India is over 100 years old." . the Ministry of Petroleum and Natural Gas in 1986 constituted a Safety Council assisted by the Oil Industry Safety Directorate (OISD) staffed from within the industry for formulating and implementing a series of self regulatory measures aimed at removing obsolescence. With this in view. The experience and knowledge gathered over the years and the various national and international codes and practices are taken into consideration. OISD constituted a number of functional committees comprising of experts nominated from the industry to draw up standards and guidelines on various subjects. Accordingly. The first edition of the document on "Layouts for Oil and Gas Installations" was prepared by the Functional Committee and published in November 1988. This document of July 1995 is the first revision prepared by the Functional Committee. operating and maintaining oil and gas installations. standardising and upgrading the existing standards to ensure safer operations. Kasturba Gandhi Marg New Delhi-110 001 iii "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. emphasised the need for the industry to review the existing state-of-the-art in designing. This coupled with feed back from some serious accidents that occurred in the recent past in India and abroad. This document will be reviewed periodically for improvements based on the experience and better understanding. Arora Shri S. Mathur (since April. Bombay Bharat Petroleum Corpn. Bombay Bharat Petroleum Corpn.K. Kapoor (since February.K.N..Bhatla Members Shri K. Bhatla/ Shri M.COMMITTEE ON LAYOUTS (First Edition . Bombay Hindustan Petroleum Corpn. Ltd. New Delhi ORGANISATION COMMITTEE ON LAYOUTS (First Revision . 1995) (In addition to the above.M. Pandarinathan Member Coordinator Shri B.P. Bombay Madras Refineries Ltd.K.Raina Shri S. Mukherjee Shri V. Ravi Kumar Member Coordinator Shri B. Ltd. Bombay Oil & Natural Gas Corpn.K.. (M). (R). Madras Engineers India Ltd. New Delhi Hindustan Petroleum Corpn. Ltd. 1995) Members Shri S.K.) Oil Industry Safety Directorate. Ltd.July 1995) Leader Shri R. (R).. Trehan Oil Industry Safety Directorate. New Delhi "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines." . Raina Shri K. review and finalisation of this document..P. Sadhukhan/ Shri S. Mukherjee Shri K. Arora Shri V. Ltd.K.K.. Ltd. several other experts from the industry contributed in the preparation. Bombay Madras Refineries Ltd. Madras Engineers India Ltd.. (M). New Delhi Oil & Natural Gas Corpn.November 1988) NAME Leader Shri R. " . ANNEXURE 1 : TYPICAL LAYOUT OF LPG STORAGE VESSELS v "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines.2 6. 3. 8.1.1 9.1 6. 5.0 7.2 8.1. 7.1 6.0 4.1 5.0 8.LAYOUTS FOR OIL AND GAS INSTALLATIONS INDEX SECTION 1.2 8.2 7.0 5.1.2 6.0 6.1.1.3 8.2 10. 2. 6.0 9.2 9.0 TABLES 1.0 5.1 8.1 7. CONTENTS Introduction Scope Definitions Plant Layout Philosophy Layout of Blocks/Facilities General Considerations Inter-distances Layout of Process Units General Considerations Process Equipment Control Room and Sub-Station Equipment Spacing within Process Units Layout of Storage Tanks General Considerations Inter-distances between Tanks / Offsite Facilities Layout of LPG Facilities General Considerations LPG Storage LPG Bottling LPG Bulk Handling Inter-distances for LPG Facilities Layout of Utility Stations General Considerations Inter-distances References Inter-distances between Blocks/Facilities Equipment Spacing within Process Units Inter-distances between Storage Tanks/Offsite Facilities (for Small Installations) Inter-distances between Storage Tanks/Offsite Facilites Inter-distances between Storage Tanks Distances from Boundary Fencing Inter-distances for LPG Facilities Inter-distances between LPG Storage Vessels and Boundary/Property Line/ Group of Buildings not associated with LPG plant.0 3. 4.0 2.1 8. LAYOUTS FOR OIL AND GAS INSTALLATIONS 1.0 DEFINITIONS (i) PETROLEUM REFINERY Petroleum Refinery is a plant where crude oil is received and processed into intermediates and finished products. This standard will however create awareness and help in selective implementation of the recommendations at existing installations. road and pipeline and filled in cylinders. (iii) facilities upstream of the Christmas tree of a well are not covered under this definition. (ii) OIL/GAS PRODUCTION PLANT Oil/Gas production plant is a plant where oil and/or gas is collected. it may not be practicable to comply with. 2. The hydrocarbon industry over the years learnt lessons from fires and explosions throughout the world and has been up-dating plant safety norms including inter-distances between facilities and their relative locations. The requirement of green belt/buffer zone beyond the plant boundary is outside the scope of this standard. At times plants are modified to operate at higher capacities or efficiencies necessitating larger storage requirements than contemplated earlier. — "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. Today's trend of large and complex plants presents substantial risk potential. This document lays down minimum requirements of layouts within the plant boundary for petroleum refineries. The minimum distances recommended many years ago need review in the context of today's environment in the industry. It is not intended that requirement of this standard should be applied rigidly to existing premises where for a variety of reasons. GAS PROCESSING PLANT Gas processing plant is a facility where natural gas is received and processed to make gas. Drilling activities and GENERAL CLASSIFICATION OF PETROLEUM PRODUCTS Petroleum products are classified according to their closed cup FLASH POINTS as follows: — — Class "A" Petroleum: Liquids which have flash point below 23 oC.0 INTRODUCTION Hydrocarbon processing and handling plants are inherently hazardous. LPG. condensate etc. stabilized and dispatched for further processing. (v) OTHER PETROLEUM STORAGE INSTALLATIONS Other petroleum storage installations include: (vi) Crude oil gathering stations Coastal storage installations for crude oil and petroleum products Marketing depots and terminals Aviation storage and fuelling stations Pipeline installations/terminals. (vii) 3. Class "C" Petroleum: Liquids which have flash point of 65 oC and above but below 93 oC. Such provision may be considered based on local environmental/ security requirements. (iv) LPG FILLING PLANT LPG filling plant is a plant where liquefied petroleum gas (LPG) is received/despatched by rail. LPG filling plants and other petroleum storage installations. Class "B" Petroleum: Liquids which have flash point of 23 oC and above but below 65 oC. initial site analysis for the proposed new construction or addition should be done carefully while considering the space allocation to the various facilities. Oil/Gas production and processing plants. For these reasons.0 SCOPE FLASH POINT "Flash point" of any petroleum liquid is the minimum temperature at which the liquid yields vapour in sufficient concentration to form an ignitable mixture with air and gives a momentary flash on application of a small pilot flame under specified conditions of test as per IS:1448 (Part-I)." . ) (b) Following points shall be kept in mind while developing overall plant layout of any installation. vii "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. Utility requirements (b) (viii) TANK HEIGHT Tank height is the: (ix) Height from tank bottom to top kerb angle for cone roof tanks Height from tank bottom to top of tank shell for floating roof tanks STABLING LINE It is an additional railway line/spur reserved for additional rake/stabling." . canteen.0 PLANT LAYOUT PHILOSOPHY A petroleum installation may be broadly considered as a group of one or more of the following units/facilities: Crude oil storage Intermediate and finished product storage LPG storage and handling facilities Process units and control room Product loading/unloading facilities (Rail. 4. first aid. In the following cases. above classification does not apply and special precautions should be taken as required: (a) Where ambient temperatures or the handling temperatures are higher than the flash point of the product. road and pipeline) Warehouses. (i) BASIC INFORMATION (a) Information on following items should be collected before proceeding with the development of overall plot plan: Process units and their capacities Process flow sequence Storage tanks list LPG storage vessels and their sizes Product despatch and mode of transport (rail. fire station. laboratory. do not fall under this classification but form separate category. petroleum wax. parking lot etc. open storage areas Number of flares Operating and maintenance philosophy for grouping of utilities Plant and non-plant buildings Environmental considerations Scrap yards and dumping ground Fire station and fire training ground Chemical/Toxic Chemical storage Storage areas for solid products such as petroleum coke.— Excluded Petroleum: Liquids which have flash point of 93 oC and above. workshop. Where product handled is artificially heated to a temperature above its flash point. bitumen and asphalt Data on following infrastructural facilities should be collected before detailed layout activity is taken up and due consideration should be given for the same while deciding plant layout: Site location map Prevailing wind direction Area topography contour map High flood level in the area Source of water supply and likely entry point Electric supply source and direction of entry point Crude oil entry point Storm water disposal point and effluent disposal point Railway entry point and marshalling yard location diagram indicating flow Liquefied gases including LPG. Road and Pipelines) Utilities generation and distribution centres Blowdown and flare system Waste water treatment facilities Administrative and service buildings (warehouse. coal. - Approach roads to main plant areas Inward/outward product movement by rail/ road and pipelines. (ii) Surrounding risks BLOCKS (a) In any process installation. dusty operations (e. Block layout should be adopted as much as possible. (c) (V) ERECTION AND MAINTENANCE (a) Erection methods shall be anticipated for all types of equipments. Maintenance methods for each type of equipment shall be identified in advance since these affect the requirements for layout. Maximum size of a block should be established based on tank farm layouts. Primary traffic roads in the installation should be clear of hazardous classified areas. (b) (iii) ROADS (a) All process units and dyked enclosures of storage tanks shall be planned in separate blocks with roads all around for access and safety. Extension of pipe sleepers and pipe way.1 GENERAL CONSIDERATIONS (iv) LOCATION "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. Both these approaches should be available for receipt of assistance in emergency. Layout of the facilities shall be made to minimise truck traffic ingress in the plant. For equipments having removable parts. Care shall be taken to facilitate future expansion without any interferene to plant on-stream. The entire area should be subdivided into blocks." .g. Orientation of flares. Equipment requiring frequent attention shall have easy accessibility. (vi) (b) (b) FUTURE EXPANSION Future expansion shall be assessed and space provision for known and unforeseen needs shall be made. reactors and fired equipments should be located away from congested areas to facilitate erection at any stage. arrangements shall be made to facilitate their removal without dismantling long lengths of piping. Orderly future expansion shall be affected by providing space adjacent to similar type of facilities for expansion. However.0. this requirement may be relaxed if not feasible. one for employees and other for product movement. Presence of ignition source shall always be contemplated beyond the boundary wall of the installation. (a) (b) Process unit(s) should be located on high ground to avoid flooding.furnaces/heaters. road crossings for yard piping shall be given due consideration. LAYOUT OF BLOCKS/FACILITIES An installation may consist of one or more of the following basic blocks/facilities: Storage tanks/offsites LPG storage and filling facilities Process units Utilities and effluent disposal facilities (e) (f) 5. Road widths and turning radii at road junctions shall be designed to facilitate movement of the largest fire fighting vehicle in the event of emergency. Rail spur shall be located close to the periphery of the plant to minimise road crossings and blockage of roads during shunting. wherever possible. Roads separating the blocks shall provide fire breaks and have facilities for fire fighting activities. Two road approaches from the highway should be provided. Free access shall be provided for hoisting the equipment. (c) (d) 5. Towers. for smaller installations. Alternative access should be provided for each facility so that it can be approached for fire fighting/maintenance/construction in the event of blockage on one route. sulphur handling) and cooling towers should be decided based on prevailing wind direction. it is recommended that plant layout arrangement should follow the general route of raw material to process unit (s) with tankages interposed as required followed by despatch facilities. (xvii) Fire water storage and pumps shall be located at a minimum distance of 60 m from hydrocarbon storage and process units." . Wherever these lines are passing through plant premises adequate safety distances shall be kept. (xii) (v) (vi) (xiii) (xiv) Petroleum coke/coal storage and handling facilities should be located as far as possible away from process units. Fire station and fire water pump house shall be located at a safe place away from hazardous areas. Height of flare and its distance from operating facilities shall be decided based on heat radiation considerations and other considerations like ground level concentration. storage tanks should be located at lower elevations. following items should be considered : (i) (ii) (iii) Layout planning should be in sequential order of process flow. (xv) Sufficient open areas should be left where construction activities can be undertaken. populated and hazardous areas. Fire station includes fire tenders. L T sub-station should generally be located at load centres in such a way that the distance between distribution transformer and farthest motor is minimum.While locating the above blocks/facilities and further sub blocks/facilities within them. Effluent Treatment Plants should be located minimum one block away from unit area. Process units should be centrally located with straight approach from main gate. Location of tall columns and furnaces should be close to road side for ease of construction and maintenance. to avoid problems due to coal dust and ash. Utility blocks should be located adjacent to unit blocks. Overhead power transmission lines shall not pass over process units. storage tanks. section 8. Area around flare should be paved to avoid growth of grass/vegetation which can otherwise provide combustible material for fires. it shall be as per clause 4. Orientation of process units should follow process flow in sequential order so that piping runs are also minimum. Sulphur recovery unit and sulphur loading area should be located close to product movement gate and away from hazardous and populated areas. Requirements for erecting tall structures should be studied before finalising the layout. electrical installations etc. (iv) Storage tanks should be grouped according to product classification. (Ref. However for petroleum depots and terminals. down wind of process units and important areas to avoid odour problems.5(V) of OISD-STD-117. (x) Flare should be located upwind of process units. air separation plants. Coal based power plants should be located away from criticalfacilities like air separation plants. as far as possible. In undulating areas. cold venting etc. They should be closer to disposal point and at lower grade to facilitate gravity flow of effluent. offsite and utility areas. Main power receiving station should be close to the fence line with minimum overhead power transmission lines passing through the installation. ix "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. One or more sub-stations could be provided to limit distances.3. Rail loading facilities should suit rail siding layout and preferably be located along periphery of the installation. (viii) (ix) (xvi) Fire station should be located close to main entry gate with straight approach to process units/other critical areas. (vii) H T sub-station should be located close to major load centres. Orientation should be to suit wind direction to avoid travel of hydrocarbon vapour over sources of ignition. Gas/Oil based power plants should be located close to process units/utility blocks and closer to Main Receiving Station. (xi) Truck loading facilities should be located close to product movement gate. A minimum distance of 50m is recommended between sulphur storage/handling and any building or boundary wall.0 of OISD-STD-106 on "Process Design and Operating Philosophies on Relief and Disposal systems"). foam equipments and fire fighting accessories. 2 INTERDISTANCES Interdistances between various blocks/facilities described above shall be as per Table-1.5." . "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. 4.1 (NOTE1) MINIMUM INTERDISTANCES BETWEEN BLOCKS/FACILITIES S." .II 11 TABLE . 1. 2. From \ To 1 36 *** 30 45 30 60 90 150 45 60 2 *** ** 45 30 60 90 150 45 30 3 30 ** T3 & T5 T3 & T5 T3 & T5 30 90 150 30 60 4 45 45 T3 & T5 T3 & T5 T3 & T5 30 90 150 30 60 5 30 30 T3 & T5 T3 & T5 T3 & T5 30 90 150 30 60 6 60 60 30 30 30 T7 90 150 30 90 7 90 90 90 90 90 90 90 150 90 90 8 150 150 150 150 150 150 150 150 150 9 45 45 30 30 30 30 90 150 10 60 30 60 60 60 90 90 150 11 45 30 90 90 90 90 90 150 12 30 30 30 30 30 90 150 13 60 30 T6 T6 T6 T8 90 150 14 60 15 60 30 30 45 90 150 15 16 30 30 30 30 30 30 90 150 30 12 30 90 30 50 50 50 60 90 150 50 90 Contd. 7. 5. 6..No. Process Units Process Control Room Storage Tank Class A Storage Tank Class B Storage Tank Class C Storage Vessels (Pressure) LPG/Other Flares-elevated Flares-ground Bulk loading racks (rail/road) LPG/POL T7 90/60 30 30 T7 T6/T760 30 12 10. 9. Fire stations/ First aid centre 150 90/60 "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. 3. 8.OISD-STD-118 Revision .. Boundary fence around installation 14. "T" indicates the table to be referred. All distances shall be measured between the nearest points on the perimeter of each facility except in case of tank vehicle loading/unloading area where the distance shall be measured from the centre of each bay." 6. open oil separators/oil collection sumps shall be categorised under the same risk and shall be located at 90m distance from heaters/boilers. However. it shall be decided based on construction. nitrogen plant 16. 5. From \ To 1 45 30 60 60 30 2 30 30 15 30 3 90 30 T6 60 30 4 90 30 T6 30 30 5 90 30 T6 30 30 6 90 30 T8 45 30 7 90 90 90 90 90 8 150 150 9 30 T7 10 30 30 11 15 50 30 30 12 15 30 6 15 13 50 30 6 30 14 30 6 6 30 15 16 30 15 30 30 90 50 50 50 15 11. 3.No. Distance between bulk loading racks and fire station shall be : (i) For LPG Gantry . API Separators/ oil sludge pit ** *** 150 T6/T7 12 150 150 60 30 12 30 90 30 50 50 50 60 90 150 50 90 90 50 50 50 15 - Distance will be 30 meters in case Control Room is blast proof and 60 meters in case it is not blast proof. the minimum safe distance can be reduced from 90m to 30m. Boiler House/ heaters 12. if these are covered from top and provided with adequate venting to safe location.12 OISD-STD-118 Revision . All distances are in metres.90 m & "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. 4. . Rail spur 13.) S. Service buildings 15.II TABLE . API/CPI. Cooling towers. 2..operation & maintenance requirements. water storage.1 (Contd. Refer OISD-STD-163 on Process Control Room Safety Notes : 1. Where distances have not been specified. physical and chemical. or change in state. Fire pump house – a building housing main fire water pumps.II ii) 7. fire control room with required communication facilities/mimic panel. purification.60 m. communication and alarm system. For POL Gantry . "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. jockey pumps.a unit having integrated sequence of operation . Fire station – a building housing facilities of parking fire tenders and keeping other ready to use fire fighting equipment for meeting plant emergencies. Service building – a building housing facilities for inspection/maintenance/other supporting services which are directly required for operation of the plant.OISD-STD-118 Revision . energy content or composition. and may involve preparation. instrumentation and the required operating & supporting personnel. 13 Definitions : Process Unit ." . separation. Compressor house should be located near the battery limits to facilitate ease in maintenance and operation. If the shut down of the units are expected at different occasions. Pumps handling hydro-carbons and materials above the temperature of 230 degree C should not be installed underneath the air fin coolers. these should be located in open area.14 OISD-STD-118 Revision .Pumps may be arranged in two rows close to and on either side of the central pipe rack.1 PROCESS EQUIPMENT (i) Process flow sequence and operating procedures shall be thoroughly understood so that equipment arrangement in the plot plan is functional. Spacing between battery limits of individual pieces of equipment shall be adequate for undertaking maintenance jobs. Heat Exchangers and vessels should be grouped together forming outer rows on both sides of the rack. Cold boxes should be located on grade or on separate elevated structures. The local control panel for soot blower control and flue gas analyser shall only be located on and near the process heater.I 6. Tall towers require frequent operating attention at upper levels. Air fin coolers should be installed above the pipe rack. FD fans shall be located away from process equipment from where they arelikely to suck hydrocarbon vapours.This will facilitate ease in maintenance and minimise risk from/for operating units due to hot jobs in the units under shut down. (xiii) No other tankage except day tanks shall be provided within battery limits of any process unit. Spacing between two process units in a complex should be decided based on shut down philosophy for maintenance of the units. (viii) Vessels having large liquid hold-up should be installed at lower heights and preferably at grade. Reboiler should be mounted on the tower so that vertical expansion will be uniform. Hence they may be located at one place so that common connecting platform can be provided.0 6. Areas around the heaters shall be graded for guiding spills away from process equipment. Clearance shall be provided for movement between reboiler and tower.Shell and tube heat exchanger should have a longitudinal clearance of at least one metre plus the length of removable bundles. Fired heaters should be kept at open end of the unit upwind from the remaining plant equipments. Adequate space should be provided around cold boxes for ease of operation and maintenance. Equipment shall be arranged in logistic process sequence for short piping runs and operational ease. then inter distances may be increased.II -118 Revision . Heaters should be located up wind at one corner of the unit. Thermo-siphon reboilers should preferably be placed close to their associated towers. Heat exchangers should be located perpendicular to the pipe rack on the outer row to facilitate pulling of tube bundles with mobile crane or by other means." . Space should be provided for removal and cleaning of heater tubes besides approach for crane. Adequate drainage should be provided around such vessels. The rest of controls shall be taken to central control room.1 LAYOUT OF PROCESS UNITS GENERAL CONSIDERATIONS 6.1. Gas compressors should have roofing and open from sides to avoid accumulation of heavier vapours/gases on the floor of compressor house. (ix) Towers/columns should be located along the pipe rack towards open areas for unobstructed erection as well as maintenance of internals at grade. (ii) (x) (iii) (xi) (iv) (xii) (v) (vi) (vii) "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. piping system design is simplified and inlet/outlet piping is minimised. Where process requirement dictates their installation above grade. thereby splitting the unit into two or more areas of equipments. Gas compressors should be located down wind from heaters so that leaked gases will not drift towards the heater. It is recommended that the unit pipe rack be kept in the centre. It should be at a safe distance where protection to instruments and personnel is ensured and non-hazardous electrical area classification is permitted.II (xiv) Flare knock out drum of the closed blow down system should be located at battery limit of the unit. Control room should be designed to cater for minimum occupancy. Transformers should be located in open area on the rear side of sub-station. Doors should be made of fire proof material. 6.OISD-STD-118 Revision . It shall be minimum 6m above the highest platform if horizontal distance of 15m from process equipment is not possible." .Each transformer shall be isolated from the other by a brick masonary wall. SPACING WITHIN PROCESS in (iii) 6.2 CONTROL ROOM AND SUB-STATION (i) Control room should be located distinctly in the process block or in the adjoining block.2 EQUIPMENT UNITS Interdistances betweenvarious equipments process units shall be as per Table-2. (ii) (xv) Blow down facilities/burried drum shall be located at one corner of the plant farthest from furnace or any fired equipment and on the lee-ward side of the unit. "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. Approach road to sub-station and transformer bays should be provided to facilitate crane movement for erection and maintenance. Electrical sub-station should be located adjacent to the control room building and should meet the requirements of electrical area classification. It should have alternate means of exit with doors opening (iv) 15 towards outside.1. Vent from Blow down facility shall be minimum 6m clear off the air fin coolers. 5 7. Air Fin CoolersHydrocarbon 12. 7 4 3 16 - 5 2 3 20 - 4 2 3 20 - 7.No. 4.5 (Hydrocarbon) Hot oil transfer pumps Fuel Oil Day tank 15 15 Pump for Class A & 20 all products above auto-ignition temp.5 6 4 2 8 5 15 4 8 7.51 2 15 8 20 7 5 4 7. 7.5 16 - 1 2 2 16 - 15 15 15 16 - 1 2 2 16 - 1 2 2 16 - 2 2 2 16 - 2 2 16 - 16 16 16 16 16 - 15 15 15 20 - 3 2 2 16 2 15 15 15 - 2 16 - 15 15 15 16 15 15 15 15 5 5 2 - 10. 2.5 1 15 1 9 15 7 5 4 7.5 1 15 1 10 15 4 2 2 7.5 2 15 2 16 20 20 16 16 16 16 Gas compressors 22.5 8 3 7. From \ To Fired heaters/ any fired equip.II TABLE-2 MINIMUM INTERDISTANCES BETWEEN EQUIPMENTS WITHIN PROCESS UNIT “This table could be used by the oil companies as a guideline for their projects.16 OISD-STD-118 Revision .5 15 7. 1.5 2 15 2 11 12 13 15 - 14 15 15 15 15 15 15 15 15 18 5 3 3 4 3 15 3 16 15 15 15 15 15 15 15 15 17 6 3 3 3 3 - 18 30 15 15 15 20 15 15 15 19 20 15 15 15 15 15 1515 15 15 15 3 3 3 7.5 7.5 15 22.5 1 7. Heat ExchangerHydrocarbon 11.5 5 15 5 4 5 6 15 7 5 5 7.5 15 16/30 3 3 3 7.5 1 7 15 15 15 15 15 7. Pumps . Reactors Distillation columns Accumulators (Hydrocarbon) 1 15 15 15 2 15 2 2 6 8 7 15 7 3 15 2 3 4 7.other Hydrocarbon 15 15 15 16/30 15 9. 5. Fired heaters control panel (local) 16 - - 15 15 15 15 15 15 15 15 15 15 20 - - 10 15 - 15 15 5 . 6. 3. Control room 13. 8. These could be suitably modified as required to suit space constraints and relevant engineering practices. Snuffing/purging steam isolation valve 14.” NOTE 1 S. 6.No.II 17 Contd. 3. 10. Fuel Oil day tanks shall be located at a safe distance of 15m from equipment except those facilities such as heat exchanger. Distance between fired heater and distillation column shall be increased to 22. 8. Blow down facility (18) and water spray deluge valve (19) are by safety considerations. Pressure Vessel/ Drums (Hydrocarbon) 16. Water spray Deluge valve 20. Fire water hydrant/monitor (16). can be relaxed to 5m. From \ To 1 18 2 5 3 3 4 3 5 4 6 3 7 15 8 3 9 3 10 2 11 2 12 16 13 2 14 10 15 2 16 15 17 3 18 15 19 20 15 2 15. 7.. Structural main (Technological platforms) 15 6 30 15 3 15 15 3 15 15 3 15 15 3 20 15 15 15 15 15 15 15 15 15 2 15 15 15 16 16 15 15 15 15 3 15 15 15 15 15 15 15 - 15 15 15 15 15 15 3 15 3 15 3 15 7. If the blow down drum is located underground. the distance from fired heater shall be reduced from 30m to 15m.5m in case of light ends such as Naphtha stabiliser. The local control panel meant for soot blower control & fuel gas analyser shall only be located on and near the process firedheater. 9.2 (Contd. The rest of controls shall be taken to central control room. TABLE . Steam snuffing/purging valve shall be located minimum 15m from only those equipments which are served bythe steam valve. Fired heater local control panel (14). Fire water hydrants/monitors 17. it shall be 30m irrespective of whether the control room is for one or more units. safe distance shall be 16m if the control room is for one unit and shall be 30m. if it is for two units. drums. Blow down facility (pumps.. .. All distances are face to face clear minimum distances in meters.) S. 4. From control room to heater. (Refer Table-5 for interdistance between tanks). operation and maintenance safe guards.5 15 - 15 15 15 - 15 - 15 - 15 2 5 16 5 - 15 5 15 2 - 15 - 15 15 - - Notes: 1. Minimum distances between equipment shall not be applicable for package items and their related appertenances.. Pipe rack (main) 18. Control room (12). Other distances indicated are recommended from erection. 5. 2..OISD-STD-118 Revision . stacks) 19. Distance between equipments not covered herein & equipments handling non-hydrocarbons shall be as per good engineering practices. Safety distances as per preceeding Table-2 for blow down facilities are for open pit location. Only distances indicated from fired heaters (1) Fuel oil day tank (7). 11. pump connected directly with the Fuel Oil system. For gas processing plants. Distances between the reactor and furnace when directly connected process-wise. However. to 20. Tanks located overhead for process considerations shall meet safety distance and shall also have dyked enclosure of RCC construction and provided with drain valves at suitable height for easy operation.m capacity and above shall be laid in single row. (f) (g) hydrostatic load. : 60. However. for excluded Petroleum. where class "C" petroleum is stored in a common dyke along with class "A" and/or class "B" petroleum. Class "A" and/or class "B" petroleum can be stored in the same dyked enclosure.1 (i) LAYOUT OF STORAGE TANKS GENERAL CONSIDERATIONS DYKED ENCLOSURES (a) Petroleum storage tanks shall be located in dyked enclosures with roads all around the enclosure. thenit shall be treated as a group of fixed roof tanks for the purpose of above limits. A free board of 200 mm above the calculated liquid level shall be considered for fixing the height of the dyke. all safety stipulations applicable for class "A" and/ or class "B" respectively shall apply.m. Fire walls should be provided by limiting the aggregate capacity of each group of tanks within. (ii) GROUPING (a) Grouping of petoleum products for storage shall be based on the product classification. Note 2 Pump stations should be located outside dyke areas by the side of roads.000 cu.000 cu.m. for excluded petroleum. (d) (e) (b) (iv) GENERAL . However. If a group of tanks contains both fixed and floating roof tanks.m. tanks having 50.0 7.II 7. The tank or tanks shall be supported on well designed foundations and shall be either buried underground or installed in the open and surrounded by wall or embankment not more than two meter high and made of earth.000 cu. concrete or solid masonry capable of withstanding fully (iii) (b) (c) FIRE WALLS In a dyked enclosure where more than one tank is located. the minimum height of dyke wall shall be 600 mm. fire walls of 600mm should be provided as explained below: (a) Any tank having a diameter more than 30m should be separated with fire walls from other tank. However. (b) Dyked enclosure should be able to contain the complete contents of the largest tank in the tank farm in case of any emergency. Interdistance between the nearest tanks located in two dykes shall be equivalent to the largest tank diameter or 30m. Tanks shall be arranged in maximum two rows so that each tank is approachable from the road surrounding the enclosure. Enclosure capacity shall be calculated after deducting the volume of tanks (other than the largest tank) upto the height of the enclosure.6 meter wide flat section on top. Class "C" petroleum should preferably be stored in separate enclosure. Aggregate capacity of tanks located in one dyked enclosure shall not exceed following values : For a group of floating roof tanks For a group of fixed roof tanks : 120.0 m above average grade level inside. B or C petroleum. (c) The height of tank enclosure dyke shall be at least one metre and shall not be more than 2. Earth wall of over 1 meter high shall have not less than 0. whichever is more. the capacity of the dyked enclosure should be based on spill containment but not for containment on tank rupture. Excluded petroleum shall be stored in a separate dyked enclosure and shall not be stored along with class A.18 OISD-STD-118 Revision .000 cu. m Interdistances between tanks storing excluded petroleum will not be governed by Table-3 and 4 and should be decided on construction.m at one installation.OISD-STD-118 Revision . (b) (ii) (c) (d) (iii) The following stipulations shall apply for the inter distances for above ground tanks storing petroleum: "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. No fire water/foam ring main shall pass through dyked enclosure." .II (a) The tank height shall not exceed one and half times the diameter of the tank or 20m whichever is less. or class "A" and "B" petroleum products with total storage capacity not exceeding 5000 cu. (iv) 7.m Interdistances between tanks and fencing shall be as given in Table-6 for tanks storing Class "A".2 INTERDISTANCES BETWEEN TANKS / OFFSITE FACILITIES (i) 19 Inter distances shall be as given in Table-3 for tanks storing class "C" petroleum. Class "B" and Class "C" petroleum products with total storage capacity of class "A" and class "B" petroleum stored exceeding 5000 cu. operation and maintenance requirements. Piping connected to tanks should run directly to outside of dyke to the extent possible to minimise piping within the enclosures. Piping from/to any tank located in a single dyked enclosure should not pass through any other dyked enclosure. The minimum distance between a tank shell and the inside toe of the dyke wall shall not be less than one half the height of the tank. Inter distances shall be as given in Table-4 for tanks storing class "A" and class "B" petroleum products with total storage capacity exceeding 5000 cu. 5 - - - 33 10.5 D or 6 9 0.3 9 4.5 - 9 4. 3.3 (NOTE1) INTERDISTANCES BETWEEN TANKS/OFFSITE FACILITIES (For small installations) S.5 9 4. 5.5 D min." . 1.5 D 0.5 8.5 D 0.5 D 9 3 0.5 3 3 9 9 0.5 9 10 3 3 3 1. 4.5 4.5 4.5 D or 6 0.5 9 4. 6.5 6 9 5 9 0.5 1.5 4.5 D min.4..5 4.II TABLE . "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines.5 min.4. 15 4.5 9 7 15 9 9 9 9 9 8 15 4.3 9 4.5 - 3 1.5 D or 6 9 9 9 15 2 0.5 4.5 - 9 4.5 D or 6 9 0.5 9 12 15 13 15 D D min. From \ To Storage tank for petroleum class A Storage tank for petroleum class B Storage tank for petroleum class C Storage / filling shed for petroleum class A Storage / filling shed for petroleum class B Storage / filling shed for petroleum class C Tank vehicle loading / unloading area for petroleum class A Tank vehicle loading/ unloading area for petroleum class B Tank vehicle loading/ unloading area for petroleum class C 1 0.5 9 4.5 - - 3 - Contd. Flame-proof electric motors 3 3 - 3 1.5 9 9 15 4.5 4.5 0.5 9 4.5 D 9 4 9 9 9 4.5 3 11 15 4.5 D 6 1. 15 4.5 D or 6 0.No..5 9.5 1.5 D 0. 2.5 D or 6 0.5 9 - 4.20 OISD-STD-118 Revision .5 D 4.5 4. 7.5 D 0.5 9 6 9 0. All distances shall be measured between the nearest point on the perimeter of each facility except in the case of tank vehicle loading/unloading area where the distance shall be measured from the centre of each bay. 4. amenities etc.m.5 9 3 10 3 11 12 13 - 11. Boundary fencing around installation 15 9 4. .5 3 9 4. within installation 13.5 3 0. 6. 4.5 D min.5 D min. Interdistances given for tanks are shell to shell in the same dyke.No. iii) The diameter of any tank storing petroleum class A or petroleum class B does not exceed 9m. Notation : "D" (-) – – diameter of the tank a distance suitable for constructional and operational convenience. Office building.3 (Contd.OISD-STD-118 Revision .5 4.5 D min. All distances are in metres.. From \ To 1 15 15 2 4. maximum thereof shall be observed. Where alternate distances are stipulated.5 6 3 7 9 9 8 4. 4..5 D min. 2.5 3 - - - - Notes: 1. Non-flameproof electric motors 12. 3 0.) S. stores.II 21 TABLE . 5. 3.5 4. Above table is applicable for installations where i) Only petroleum class C is stored. ii) The total quantity of petroleum class A and class B stored above ground in bulk does not exceed 5000 cu. 3 4 9 9 5 4. 9. Above table is applicable for installations where total quantity of petroleum class A and class B stored above ground in bulk exceeds 5000 cu. Table-5 shall be referred. 8 15 8 15 - 8 15 - 8 15 - 8 8 - Notes : 1.II TABLE . "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. 15 15 - 15 - - - - - 8. All distances shall be measured between the nearest points on the perimeter of each facility except in the case of tank vehicle loading/unloading area where the distance shall be measured from the centre of each bay. 3. 2. From \ To Storage tank for petroleum class A Storage tank for petroleum class B Storage tank for petroleum class C Storage / filling shed for petroleum class A or class B Storage/filling shed for petroleum class C Tank vehicle loading/ unloading area for petroleum class A or B Tank vehicle loading/ unloading area for petroleum class C Flame proof electric pump motor Non-flame proof electric pump motor 1 T5 T5 T5 15 2 T5 T5 T5 15 3 T5 T5 T5 15 4 15 15 15 5 15 15 8 6 15 15 8 15 7 15 15 15 8 8 8 8 9 15 15 15 5. 1.4 INTERDISTANCES BETWEEN STORAGE TANKS/OFFSITE FACILITIES S.22 OISD-STD-118 Revision . 2. – – any distance suitable for constructional or operational convenience. 15 15 15 15 8 8 15 8 8 - - 8 15 7. 4. 6. 3.No." . This table is applicable for class C petroleum storage also alongwith class A & B petroleum as per limits specified under note-2 above. All distances are in metres. 4.m or where the diameter of any such tank for the storage of petroleum exceeds 9 m. Notation: (-) T5 5. All tanks with diameters upto 50 metres All tanks with diameters exceeding 50 metres (D + D) / 4 (D + d) / 4 (D + d) / 6 (D + d) / 4 Notes : 1.m. Item Floating Roof Tanks Fixed Roof Tanks (Class A & B Petroleum (D + d) / 4 (D + d) / 3 Class C Petroleum 1. . 2. 3. If the interdistance (for class A & B) calculated as above are less than 15m. 5.II 23 TABLE . This table is applicable for installations where aggregate storage capacity of class A and class B petroleum stored above grade exceeds 5000 cu. Notation: D – diameter of larger tank in metres d 4.OISD-STD-118 Revision . – diameter of smaller tank in metres 2. No.then minimum of 15m or 0. Interdistance between class A/B storage tanks and classC storage tanks shall not be less than 6 metres. or where the diameter of any such tank for the storage of petroleum exceeds 9 m.5 INTERDISTANCES BETWEEN STORAGE TANKS Sl. Distances given are shell to shell in the same dyke.5 D or d shall be followed. Above table is based on the assumption that property beyond the boundary line is either protected or adequate green belt is provided as a safety buffer where no structure exists. 3.m. "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines.No. This table is applicable for facilities in an installation where total quantity of petroleum class A & B stored above ground in bulk exceeds 5000 cu. Installation 1. Storage tank for Petroleum Class A Storage tank for Petroleum Class B Storage tank for Petroleum Class C Storage/filling shed for Petroleum Class A or Class B Storage/filling shed for Petroleum Class C Tank vehicle loading/unloading area for class A & B petroleum Tank vehicle loading/unloading area for class C petroleum 5.24 OISD-STD-118 Revision . Property beyond property line is deemed protected if it is within the jurisdiction of public Fire Brigade or plant's own Fire Brigade. 6. or where the diameter of any such tank for the storage of petroleum exceeds 9 m. 2. All distances are in metres. having 3.6 (NOTE1) DISTANCES FROM BOUNDARY FENCING Minimum Distance from Boundary fencing around Installation ** ** ** 15 S. liquids. Notation: "D" – diameter of larger tank in metres. 10 Notes : 1. 4." . 10 20 7. 2.II TABLE . (ii) For tanks with weak roof-to-shell joint : The above distance shall be D/2 (minimum 20m) for tanks having approved foam or inerting system and the tank diameter not exceeding 50m. ** (I) Distance from Floating roof tank to boundary fencing for stable and boil-over protection for exposure shall be D/2 (minimum 20m). 4. II 25 .OISD-STD-118 Revision . (b) (c) (d) (iii) SPILLS AND LEAKS (a) Spillage collection shallow sump shall be located at a distance where the flames from sump fire will not impinge on the vessel. However in case of one sphere. RCC roofing should not be used to the extent possible. Cylinders shall be stacked vertically. Filling machines and testing facilities shall be organised in sequential manner distinctly in a separate area.1.m. ii) LOCATION (a) Longitudinal axes of horizontal vessels (Bullets) should not point towards other vessels. Curb wall around the storage tank shall have a minimum height of 30cm. Any vessel in one group shall be separated from a vessel in another group by a minimum distance of 30m.26 OISD-STD-118 Revision .1 LAYOUT OF LPG FACILITIES GENERAL CONSIDERATIONS (c) it shall not exceed 60cm at shallow sump position. 8. Separate dedicated manifold shall be provided for each group. Storage vessels shall be laid out in single row both in case of the spheres and bullets. Storage vessels should be located down wind of process units. Each group shall be provided with a curb wall. However (b) (c) (b) "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines.0 8. This distance shall not be less than the diameter of the nearest vessel or 15m whichever is higher. LPG storage vessels shall not be located within the same dykes where other flammable liquid hydrocarbons are stored. There shall not be any deep ditches in the surrounding area to avoid LPG settling. Filled LPG cylinders shall not be stored in the vicinity of cylinders containing other gases or hazardous substances. (d) 8. This will also minimise the chances of overfilling of adjoining vessels due to gravitation. (iii) OPERATION (a) Stacking areas for empty and filled cylinders should be located separately.II 8. A typical layout plan of LPG sphere area with major safety requirements of distances. vital process equipments and control room. the sump size shall be equal to layout of two spheres. important buildings and facilities. Top surface of the vessels installed in a group should be on the same plane so that safety blowout from one vessel does not affect the other vessel.1. is enclosed at Annexure-1 for general guidance.2 LPG BOTTLING (i) LOCATION LPG bottling facilities should be located at a safe distance from other facilities with minimum ingress to trucking traffic and downwind to storage as far as possible. Storage vessels shall not be stacked one above the other. Storage shall be kept on or above grade and never below grade in cellar or basement. There shall not be any depressions. (ii) CONSTRUCTION Bottling section shall be of single storey having roofing and open from sides for adequate ventilation so that leaked gas can drift away.1 LPG STORAGE (i) GROUPING Vessels shall be arranged into groups each having a maximum of six vessels. Capacity of each group shall be limited to 15000 cu. Spheres and bullets shall be treated as separate groups with 30m safety distance between two groups. large ditches and low lying areas around LPG storage as the leaked gas can accumulate. pump station location etc. as otherwise evaporation of spilled LPG may get affected." . being heavier than air. The capacity of the collection sump shall be as per drawing enclosed at Annexure-1. drainage sump. The bay should be designed in such a way that the driver's cabin will be facing the exit direction and shall have no obstruction. (ii) Rail loading/unloading of LPG should be restricted to a maximum of half rake. this shall be done on two separate rail gantries having a minimum distance of 50m.3 LPG BULK HANDLING (i) LOCATION (a) LPG truck loading/unloading station shall be located in a separate block and shall not be grouped with other products. except relating to service for the same gantry. (b) LPG rail loading/unloading station shall be located on a separate rail spur and shall not be grouped with other products. Maximum number of LPG tank lorry bays shall be restricted to 8 in one group. .1. 8. (c) 27 LPG loading/unloading rail gantries shall be separated from other rail shunting facilities by a minimum distance of 50m. In case of 8 wheeler wagons half rake unloading/ loading capacity shall be 600 MT. If full rake loading/unloading is envisaged.2 INTERDISTANCES FOR LPG FACILITIES Interdistances for LPG facilities shall be as given in Table-7. 8.II (d) Trucking traffic shall be smooth to avoid blocking/ obstruction for loading and unloading of cylinders.OISD-STD-118 Revision . presently capacity of which is 500 MT. All distances are in metres.7 INTERDISTANCES FOR LPG FACILITIES S. 6. Distance of stabling line shall be as per minimum Railway Standards.II TABLE . 1. not associated with LPG plant Shed-LPG/Cold repair shed/ cylinder evacuation facilities Tank Wagon Gantry Tank Truck Gantry Rail spurs Pump house/Comp. 1/4 of sum of diameters of adjacent vessels or half the diameter of the larger of the two adjacent vessels whichever is greater. 2." . 30 30 30 15 60 30 30 30 30 ** 15 30 30 15 60 30 50 50 30 60 30 50 50 30 60 15 30 30 60 60 60 60 60 - Notes : 1. house(LPG) Fire Pump house 1 * T8 2 T8 3 30 30 4 30 30 5 30 30 6 15 30 7 60 ** 3. From \ To LPG Storage vessels Boundary/property line/ group of buildings. 5.No. 7.8 * ** 3. "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. Any distance for operational convenience. Notation: T8 – Refer Table .28 OISD-STD-118 Revision . 2. 4. 10 .8 (NOTE1) INTERDISTANCES BETWEEN LPG STORAGE VESSELS AND BOUNDARY / PROPERTY LINE / GROUP OF BUILDINGS NOT ASSOCIATED WITH LPG FACILITIES S. Capacity of Each Vessel (Cum.20 21 .OISD-STD-118 Revision .M.450 451 . 4.II 29 TABLE .40 41. 6. 350 351 . 5. of water) Distance 1.No. 3.750 751 . .3800 15 20 30 40 60 90 Note : All distances are in metres. 2. These may be located in the boiler house unit block to minimise the spreading ofvarious utility blocks around the process unit. Fuel oil heating and pumping facilities may also be located within the boiler house unit block. Air compressors. However if it is necessary to provide smoking booths. these should be located at a safe distance of : (i) (ii) 9. 7. but down stream of wind direction so that the foul odour that may be present at times does not affect the plant personnel and neighbourhood areas." . OISD-STD-144 Distribution. land fill areas for disposing off solid waste etc. NFPA Standard No.1 LAYOUT OF UTILITY STATIONS GENERAL CONSIDERATIONS Boiler House. OISD-STD-117on Fire Protection facilities for Petroleum depots and terminals.1976. OISD-STD-116 on Fire Protection facilities for Petroleum Refineries/process plants.0 9.30 "Flammable and Combus-tible Liquids Code". "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. 10.30 OISD-STD-118 Revision . preferably downstream direction of wind to avoid corrosion of the equipments in process areas. 5. Locating the waste disposal facility near the boundary wall also eliminates the vehicular movement in process areas in case solid wastes are to be taken out of installation for disposal. The steam generation facilities block should preferably include boiler feed water pump. should preferably be located by the side of boundary wall. on LPG Bottling and 2. 4. which form the integral part of the steam generation facilities. cooling tower blowdown. Petroleum Rules .2 30m from hydrocarbon source in case of oil refinery/storage installation. SMPV Rules . Cogeneration. sludge.. OISD-STD-106 on Process Design and Operating Philosophies on Relief and Disposal Systems. fecal etc. 60m from hydrocabon source in case of LPG/Gas Processing Plants. When external power grid is interconnected with plant power generation facilities. iv) The waste disposal facilities like effluent channels. ( i) ELECTRICAL Electrical generation facilities should be located near the process unit block because such electrical generation units normally supply steam to the process units e. chemical block for boiler house etc. to facilitate ease of operation. (iii) WASTE DISPOSAL FACILITIES Separate collection system should be provided for different types of waste generated in the process plant such as oily water. 6.1981. either the power plant shall be located at the side of boundary wall or the external power transmission lines shall be taken underground upto the interconnection grid inorder to minimise the length of overhead transmission lines within the plant. INTERDISTANCES Interdistances between various utility stations and other facilities shall be as given in Table-1. caustic and acidic effluents.II 9.g. fuel oil facilities (for generation of steam) shall be located in separate block adjoining the process unit blocks. (ii) COOLING TOWERS Cooling towers should be located away from process unit area.0 REFERENCES 1. SMOKING BOOTHS Smoking booths should not be provided in hydrocarbon industry. 3. The plant air compressors and drying units should preferably be located in the boiler house unit block. XX NOTES : 1./SEC. 3.1 TYPICAL LAYOUT OF LPG STORAGE VESSELS Section .II 31 ANNEXURE . 100.E. LEGEND : DVA Deluge Valve Assembly ...OISD-STD-118 Revision ... 5 KG. SIZING CRITERIA FOR SUMP—FULL CONTAINMENT OF LPG SPHERE WITHIN KERB AREA IS NOT ENVISAGED HOWEVER THERE IS CHANCE OF SMALL SPILL OFLPG IN THE STORAGE AREA IT IS ASSUMED THAT THE LEAK WILL BE ARRESTED WITHIN ABOUT AN HOUR THE CONTAINMENT VOLUME FOR ONE HOUR LEAK CORRESPONDING TO LARGEST NOZZLE SIZE AND LIGHTEST MATERIAL IS 18 MT OR ABOUT 35 M3 WITH A MAXIMUM LIQUID COLLECTION RATE OF APPROX. Fire Water Piping (Not to Scale) .. ALL DIMENSIONS ARE IN METRES TOP SURFACE OF ALL VESSELS INSTALLED SHALL BE IN THE SAME PLANE. ALL LEVELS ARE WITH RESPECT TO HIGH POINT OF PAVEMENT LEVEL I. 5.. 2. 4.. WATER SEAL SHALL BE PROVIDED AT OUTLET FROM SHALLOW SUMP.00 PROTECTIVE WALLS TO BE PROVIDED IF THE VALVE IS WITHIN 30 M FROM SPHERE SHELL. 6. " .32 OISD-STD-118 Revision .II NOTES "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines. OISD-STD-118 Revision .II 33 NOTES . 34 OISD-STD-118 Revision ." .II NOTES "OISD hereby Expressly Disclaims any liability or Responsibilities for Loss or Damage Resulting from the use of the OISD Standards/Guidelines.