Introduction This report presents uses of passive and active fire protection systemsused in the oil and gas industry to minimize the risk of accidental fires. Allapplication will be set in accordance with British National Standards andguidelines in order to apply the most efficient fire prevention techniques. Theapplications of the fire control system will be set in accordance withappropriate designing, operations, and maintenance of the entire manufacturingfacility in order to deliver sufficient fire prevention and awareness. Scope This report presents fire prevention methods applied in the petroleumindustry to minimize the risk of accidental fires and designing, inspection andmaintaining of fire control systems. The fire response system should provideearly response in the event of fire to minimize the widespread of fires anddamage to property. Different methods of analytical application more extensiveto meet special situation will be briefly mentioned. This report applies to oil and gas industries which are mainlyconstructed in hazarders environments which accumulation of dangerous vaporsoccurs.
Enclosed areas, such as quarters buildingsand equipment enclosures, normally installed on this type platform, areaddressed. Totally enclosed platforms installed for extreme weather conditionsor other reasons are beyond the scope of this Report. Objectives · Prevent escalation ofaccidental of fires by implementing spacing that effectively separate theprocess unit, process drainage system, buildings and large structure.
· Avoid seriousinjuries and loss of life by providing necessary means of approach foremergency responders to a fire and access for workforces to isolate equipment.· Provide earlydetection to prevent the spread of fire and warning devices and to enableemergency systems to operate and shutdown. · Safeguard structuralsteel by providing passive and active fire safety systems in dangerous areas Oil and Gas Industry Codes, Standards and RecommendedPractices Various establishmentsdeveloped standards, codes, specifications and recommended practices which areapproved by the government and oil and gas industry.
Reasonable considerationwith latest edition of the publications must be considered while setting upfire prevention applications like designing, installation and operation of firesystems. Information provided on some of these publications listed below is notall linked to the oil and gas industry some of these are not applicable to oiland gas operations; · Health and Safety at Work etc Act 1974 (HSWA),Sections 2 and 3 · Offshore Installations (Safety Case) Regulations2005 (SCR05), Regulation 14 · Offshore Installations (Prevention of Fire andExplosion, and Emergency Response) Regulations 1995 (PFEER), Regulations 5, 9,12 and 13 · Offshore Installations and Wells (Design andConstruction, etc), Regulations 1996 (DCR) Regulation 5 · Ignition and Fuel Sources The three fundamental sources that must be present for fire to igniteare air (oxygen), fuel and source of ignition. Eliminating one of the threesources prevents the like hood of developing an accidental fire.Fuels Fuel is categorized according to the type of fire they produce on thebasis of the material burring. To facilitate the proper use of extinguishers ondifferent types of fires, the Health and Safety has classified fires asfollows:Class A Fires; are mainlycombustible materials like; cloth, wood, paper, rubber and plastics. Thesematerials are mainly found on offshore platforms. Building materials,framework, fiber ropes, skids and Supplies-wood decking. Waste materials andcleaning rugs and tarpaulins ClassB Fires; are categorized as flammable liquids, gasesand grease.
These materials are mainly found on offshore platforms e.g. Oilsand condensate, gas and vapors or hydrocarbons. Building materials, paint,welding and cutting gases. Operating materials and heat transfer fluids,hydraulic fluids, fuels, glycols and lubricants. ClassC Fires; are mainly energized electrical apparatus. Inthis particular case, electrical non-conductivity of the extinguishing agent isimportant.
The classification of the fire changes to Class A or B whenequipment is de-energized. ClassD Fires; Class 0 fires are mainly combustible metalslike; zirconium, sodium, and magnesium. Ignition Sources Ignition arises due to sufficient heat transferto cause combustion. Element influencing resultant combustion are energy,temperature, and exposure. The ignition sources that might be found on offshoreproduction are; Chemical Reaction. The possibility of chemical reaction producing heat is likely.
The heatproduced is likely to ignite the substances reaction on nearby materials.Chemical reaction that is likely to occur on an offshore platform spontaneous combustion.Offshore facilities producing sulfide are likelyto develop iron sulfide as a cause of corrosion. Spontaneous combustion when exposedto air is likely to occur due iron sulfide producing a source of heat. Fire prevention Practices Well-designed facilities and training of safe operation producers canbest the protection against the occurrence of fire.
The designed facilitiesshould operate to account for all the necessary risks associated like temporarysituation like workover, drilling and construction. The operating practicesmust be able to eliminate sources of fuel in the event of a fire. Facility Design The facility must bedesigned to provide mitigation in the event of a fire, stop ignition of thosethat do esca and should also contain hydrocarbons. The following measures thatshould be considered are;Platform Safety System; Platform Safety System employs an importantrole in preventing fire and minimizing the effect their effect. AbnormalEquipment Arrangement. The equipment should set up on the platformto provide maximum separation of fuel sources and ignition.
Guideline fororganizing equipment can be obtained from BSC. Certain attention must be applied to thepositioning of fire vessels and situation of temporary equipment duringoperation, completion, construction tasks.Prevention of ignition Devices. The equipment must be equipped with sparkand flame arrestors to avoid sparks from discharging.
Recommended guidance ispresent in (BSC) Hot surface protection. “According to BSC the temperature in excessof 400f (204 C) must be safeguarded from mist and hydrocarbon liquid, andsurfaces in excesss of 900 F (482 C) must be safeguarded from flammable gasesand fumes. This should refer to BSC….
Fire Barriers; constructed with fire resistant propertiesare beneficial in special conditions to stop the wide spreading of forces andprovide a head shield. Fire barriers must be carefully located to avoid thepossibility obstructing of natural ventilation to stop the accumulation ofhydrocarbon fume and gases. Additional information regarding fire barriers canbe obtained from BSC. Electrical Protection; protection for electrical sources necessaryprovided by the designing and installation of equipment in accordance with(BSC). Combustible gas can be determined by gas dictation unit with alarmactivation or system shutdown.
The gas dictation system alarms certainparameter set by personal, the best will be to set alarm activate the baser onlower or higher gas Bulk storage; The records of flammable fluids must becarried out regular with operation FireDetection and Alarms General The fire detection and alarms system should be designed to energize atearliest stages of fire to prevent the widespread fire. FireDetectionPremature detection of fires is essential to reduce damage. Firedetection can be carried out by automatic devices or by personnel observation. Personnel Observation; personnel may noticefire and activate the alarms before automatic detection.Automatic Fire DetectionSystem; The main function of automatic fire detection system is to alarm andalert personals of the fire hazard and identification of the location of thefire. The automatic fire detection may also be used to eliminate the firehazard by the means of activation of emergency stops, isolating machinery,isolating fuel sources, starting fire pumps and trigger fire extinguishingsystem with agents like, water, form and dry chemical.
Fusible Loop System; Fusible Loop Systemcontaining a pressure pneumatic lines which are well positioned near fusibleelements are mainly used as automatic fire detection system. If the design ofthe system is systematically allied using the best practices and industrialguidelines can be very reliable. However, filer to execute this system can leadto undictated fires at premature stages. Specific caution must be taken into account during selection oftemperature rating for fusible elements. Electrical Systems; electrical firedictation system consist of central fire monitoring system located at thecontrol panel. The application of fire alarms must be properly installed practicingspecific guideline to ensure that the system is effective in the event ofaccidental fire. The electrical fire system has calibration options andautomatic testing features. The factors required to select the type of detector are; classification,type of combustible material sensor speed of response, and electrical area ofclassification.
Additional factors should be considered like spurious alarmscaused by lightning strikes and environmental disaster. The system has toinstalled in accordance with Flame detectors; flame detectors deliverhigh speed response in the event of an accidental fire. The flame detectorsmust not be vulnerable to false alarms due to environmental factors; therefore,it might desirable to pair the devices using appropriate voting system e.
g.(UV/IR) to lower false alarms. Heat detectors; are normally used in areas where high speeddetection is not required. The system mainly requires less maintenance becauseof less sophisticated construction methods is used.ALARM SYSTEMS AlarmsSystems, must be installed on manned according to (BS)regulation.
General Alarms, Manned platforms should have manualactivation points throughout entire structure and visual alarm must be installedin high noise areas. The manual alarm must be positioned near evacuation routesand special attention must be given to delivering means to initiate alarms atESD locations. Fire Water Systems Fire water systems are generally installed on offshore platforms provideexposure to safety, for control of burning. The designing principles must bestrategically applied and may involve coverage of platforms equipment likeglycol regenerators, storage, compressors, shipping and processing pumps. Thefire water system must able to deliver the required function designed toperform. The system should able to provide personnel with means of preventingfire quickly and effectively before major damages occur. Fire protection guidelines states a fire protection system that can be controlledby one or two personnel must provide sufficient fire control equipment Fire water pumps and all accessories exposed to harsh condition must beconstructed with material resistant to corrosion.
General Passive fire protectionsystem plays a major role in protection of structural building, equipment andpersonnel from harm by fire. Information regarding maintenance, rating andpenetration found in Appendix F. Passive fire protection is commonly referredto as (PFP) in government regulations. Passive Fire Protection Fireproofing;provides a degree of fire resistance for protected substrates and assemblies. The fireproofingobjectives; · Toprovide protection to structural steel to a certain degree until emergencyfirefighting capabilities are deployed to mitigate the fires.· Tomaintain plant equipment that must keep on operating during the event of a firelike remote operated emergency stops, critical electrical instruments,depressing valves and actuators, requires fire proofing to remain operable fora distinct period of time.
· Toensure the requirement of fire proofing are integrated with drainage system.Fireproofing Materials Different types offireproofing materials available and currently in use in the industry. These materialsrange from preformed inorganic panels, masonry blocks, artificial mineral fibers,lightweight concrete, preformed inorganic panels and ablative mastics, andsubliming. Material which are mainly used in the oil and gas industry, arebroken into two groups active and inactive insulants. Active insulants experiencechemical reaction and physical when visible to fire and inactive insulants donot.
Active insulants; are mainly available as ceramic fiber or similar fireproofingmaterial buildings in an epoxy based matrix which contain additional chemicals designedto produce some chemical and physical effect when exposed to heat. Typical activeinsulants are obtainable in multiple part mixtures which form slurry suitablefor spray application when mixed together. Inactive insulants; are grouped in two general categories cementitiousmaterials and artificial fibers likemineral wool or ceramic fiber. The cementitious materials are effectively cement-based materials of a fire brick refractory mixture, which are usually mixed asa slurry and spry-applied. Artificial fibers insulate are available indifferent forms bulk, panels, blankets etc.
foam systems Foamforming additives increase the effectiveness ofwater in controlling pooledliquid-hydrocarbon fires. A tire fighting foam is a stable aggregation of smallbubbles of lower density than water or oil having a tenacious quality forcovering and clinging to horizontal or inclined surfaces. It has the capabilityof flowing freely over a burning liquid surface, cooling the liquid, and form-ing a tough, air-excluding, continuous blanket to seal combustible vapors fromaccess to air.
Foam systems are not effective on gas pressure tires or gratedareas. NFPA 11 Foam Extinguishing Systems should be consulted whenplanning, designing, or installing foam systems. Foamsmay be employed using (I) hose stations, (2) fixed systems, or (3) portableextinguishers and should capable of being actuated manually. The foaming agentmay be applied by directly introducing foam concentrate into the fire watersystem or may be applied as a premixed solution of concentrate and water. Foammay be stored in a tank or in the vendor’s shipping container.
The storagelocation(s) of foam concentrate and premixed solutions should be selectedconsidering the difficulty to replenish the system during an emergency, and theminimum ambient temperature because foam concentrates and premixed solutionsare subject to freezing. The foam concentrate must be kept in ade- quate supplyand not contaminated or diluted and the operator should follow themanufacturer’s recommendation for testing. When dry chemical and foamextinguishing agents can be used at the same location, compatibility of the twoproducts should be confirmed with the manufacturer(s). a.
Concentrate Proportioning. Foam concentrates are available for mixingwith water in fixed proportions; commonly, one through 6% mixtures with water.The correct amount of concentrate may be introduced directly into the firewater system by use o f either eductor stations or diaphragm tanks. I.Eductor Stations. A simple means to supply foam to a hose station isthrough the use of an eductor to pick up the foam and proportion it into thewater stream. The main disadvantage of an eductor is the pressure loss acrossit (on the order of one- third).
This loss must be taken into account in thedesign of a system. Conventional fire hose nozzles are available that willprovide sufficient aeration to form a foam. Because eductors are sensitive toback pressure, fixed rate nozzle gallonage rating and eductor ratings mustmatch. Manufacturers’ data should be consulted for maximum lengths of hose thatcan be used. Actual length of hose used should not exceed the manufacturers’recommendation less equivalent lengths of fittings, etc., downstream oftheeductor.
Eductor concentrate hose stations can be provided in a packagecontaining all the components pre- assembled, including a concentrate storagetank. b.Premix Systems. Premix systems may be used when a self-contained firefighting system is desired.
A means of storing the solution is required alongwith a means to expel the solution. Commercial equipment is available for thispurpose and must be tai- lored to fit a particular application. Premixedfoam-water solutions should be periodically tested and replaced to ensure theirproper concentration and chemical integrity. DRY CHEMICAL SYSTEMS The dry chemical systemextinguishes fires by chemical reaction.
The system is very effective forreduction flames it doesn’t cool down the fire. Dry chemicals are normally usedfor portable extinguishers, although they can be used in fixed systemapplication. The dry chemical is deployed as a powder driven by compressed gaspropellant. Inhalation of the chemical powder poses injury, and can bedissipated by wind. The power is likely to cause corrosion to electrical components. The risk of potential fires must be considered in choosingthe type of dry chemical BSC should be consulted when planning, designing, orinstalling dry chemicals. Water systemsWatermist systemsprovide rapid cooling effect by extinguishing fire, combined with oxygen at theflame source as the mist is flashed into steam.
Watermist systems are used forsprinklers, fixed gaseous system. Utilizes for watermist are distilled waterand leave deposits. The watermist system requires electrical equipment toisolated before deployment of water mist.Types of Watermist Systems; are designed to limit dangers that come along with accidentalfire by protecting multiple locations. The systems listed below are the two-basicstructure of watermist;High pressure systems; water is distributed by a single high-pressurepiping system which at operates at 150psi- 4,000psi compressed gas pressure andthe fresh water is propelled by nitrogen. Low pressure system works at 150psi.
Compressed air and water runs at separatelyin each nozzle, where they mix to create mist.Fixed Systems Considerations. Water system use less water compared to sprinkling system. The space and volumerequirements for gaseous systems are comparable to watermist system Fire Protection Zone FireProtection Zone (FPZ) is a zone where there is a possibility for triggeringprocess fire that steel supporting structures inside the FPZ requires to befire proofed and must be designed with adequate drainage as possible forspillage of flammables; FPZ includes Groundlevel within 9 meters horizontally and 12meters vertically that has equipmentwith high fire possibility in scenario of fuel release. Raised surfaces orplatforms that could retain substantial capacity of liquid hydrocarbons. Suchraised floors or platforms shall be treated as were on the ground floor levelfor analysing the vertical distance for fireproofing.
Machineryrotating, 9 meters horizontal and 12m vertical distance will be taken from the expectedsource.
