natural gas transmission pipeline safety related presentation.pdf

natural gas transmission pipeline safety related presentation

1. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 1
Measures adopted for Monitoring
Safety of Natural Gas Pipelines
By
S. P. Garg
General Manager (HSE)
Corporate HSE Department
GAIL (India) Limited
Email: [email protected]

2. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 2
Natural Gas
Naturalgasisanaturallyoccurring
hydrocarbongasmixtureconsisting
primarilyofmethane,butcommonly
includesvaryingamountsofotherhigher
hydrocarbonsandalesserpercentageof
carbondioxide,nitrogen,andhydrogen
sulphide.
Itiscolourless,shapelessandodourless.
Naturalgasisanenergysourceoften
usedasafuelforheating,cooking,and
electricitygeneration.
Itisalsousedasfuelforvehiclesandasa
chemicalfeedstockinthemanufacture
ofplasticsandothercommercially
importantorganicchemicals.

3. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 3
Pipeline System
Therapidgrowthofbusinessallovertheworldrequiresincreasing
hydrocarbontransportcapacity.
Apipelineisactuallyasystemofequipmentdesignedtoallowmaterialto
flowcontinuouslyorintermittentlyfromonelocationtoanother.
Withsophisticatedtechnologiesprovidingincreasedapplications,pipelines
aregainingadvantageoverothermeansoftransportduetoeconomicand
safetyconsiderations.

4. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 4
Hydrocarbon Pipeline Network in the World
0
500000
1000000
1500000
2000000
World Total United State India
1942669
793285
29684
Hydrocarbon Pipeline Network (in KM)
(Year 2010)
TheUnitedStateshaslargestpipelinenetworkintheworld.Itsnaturalgas
pipelinenetworkisahighlyintegratedtransmissionanddistributiongrid
(548,665km)thatcantransportnaturalgastoandfromnearlyanylocation
inthelower48States.

5. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 5
Natural Gas Pipelines (in KM) in India
10000
1400
2000
500
0 2000 4000 6000 8000 1000012000
GAIL
RIL
GSPL
Others
Indiahasacountrywidenetworkofapprox14,000kmsofgaspipelines(andanother
approximate)12,000kmsofpipelinesareunderconstruction.
By2017Indiawillhaveanaturalgaspipelinegridofapprox30,000-kmsconnecting
consumptioncentrestosourcesoffuel.

6. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 6
Natural Gas – Production, Transmission & Distribution
Source: Internet

7. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 7
Natural Gas Pipeline System
ANaturalGaspipelinesystemmaycontainfollowingelements:
BuriedPipelines
AboveGroundPipelines
CompressorStations
IsolationValves–Manually,RemotelyorAutomaticallyactivated
ReliefValves–PressureorThermal
PipeBridgesorotherSupports
CasingSleevesunderRoad/RailCrossing
LeakDetectionSystem
PigLaunchers/Receivers
ControlSystems

8. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 8
Natural Gas Pipeline System

9. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 9
Hazards associated with NG Pipelines
NaturalGasishighlyflammablesubstance,transportedthroughcross
countrypipelinesathighpressureoftenclosetocentresofhighpopulation
orthroughareasofhighenvironmentalsensitivity.
NaturalGaspipelinesystemposeseverehazardproblemsforhumanbeing
andpropertyinthevicinity.
ProvisionofprotectivemeasuresareessentialforsafeoperationofNG
Pipelinesystem.Therequirementisbasedon
oHazardouspropertiesofNaturalGas.
oQuantityofNaturalGas,whichcouldbereleasedanditseffect.

10. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 10
Properties of Natural Gas
NATURAL GAS : CHEMICAL FORMULA : C
nH
2n+2, n=1,2.....
PROPERTIES OTHER CHARACTERISTICS
Type of chemical
Physical form
Ignition temp.
o
C
Flash point
Explosive limits % Vol in air
Solubility in water
Vapor Density (Air=1)
Sp. Gravity
: Flammable gas
: Gas
: 535
o
C
: Not available
: 5 to 15
: Insoluble
: 0.6
: 0.42
Colorless,odorlessgascanbe
compressedtoliquidatverylow
temperature.
HAZARDS PRECAUTIONS EXTINGUISHING AGENT
FIRE:HighlyInflammable
EXPLOSION:Gasformsan
explosivemixturewithair.
Noopenfire,sparks,nosmoking.
Useexplosion-proofelectricalEquipmentGas
testswithLELMetersuitableformethane.
Shuttingoffsupplyisessentialbefore
extinguishingfireusingdrychemical
powder.
SYMPTOMS PRECAUTIONS FIRST AID
Inhalation :Dullness,
breathlessness
Ventilation,localairextraction,useof
respirator.
Removethepersontofreshairand
resorttoartificialrespirationif
necessary.Reportformedicalattention
DISPOSAL STORAGE ANTIDOTES
Intermittent coldflaring Storage in cool, well ventilated place and
isolate for oxidizing agents.
Outdoor or detached storage is preferred.
NIL
Additionalinformation:Highconcentrationinaircauseoxygendeficiencyleadingtounconsciousness.

11. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 11
Hazards of Natural Gas
FireHazard:Thefireisaprocessofburningthatproducesheat,lightand
oftensmokesandflames.Theeffectoffireonthepeopletakestheformof
skinburnonexposuretothermalradiation.
Radiation Level
(kW/m
2
)
Observed Effect
37.5 Sufficient to cause damage to process equipment
25
Minimum energy required to ignite wood at indefinitely long exposures (non-
piloted)
12.5
Minimum energy required for piloted ignition of wood, melting of plastic
tubing
9.5 Pain threshold reached after 8s; second degree burns after 20s
4
Sufficient to cause pain to personnel if unable to reach cover within 20s;
however blistering of the skin (second degree burns) is likely; 0: lethality
1.6 Will cause no discomfort for long exposure

12. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 12
Hazards of Natural Gas
FlashFire: Aflashfireoccurswhena
cloudofflammablegasandairisignited.
JetFire:Ajetfireoccurswhenaflammable
liquidorgasisignitedafteritsreleasefrom
apressurized,puncturedvesselorpipe.
(8kg/s–35m)

13. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 13
Hazards of Natural Gas
Explosion (Unconfined Vapour Cloud Explosion):
Anaccidentalescapeofflammablematerialtoformacloudandobtained
delayedignition.

14. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 14
Hazards of Natural Gas
Fire erupted in one of the Natural Gas Pipeline
Minneapolis—Anaturalgas-fueledfireeruptedinsouth
MinneapolisonThursdaymorning,March17,2011.The
fireforcedInterstate35Wtocloseinbothdirections,
thoughitreopenedlateinthemorning.Therewereno
reportedinjuriesandthefirewasextinguished.
Rupture of Transcanda Natural Gas Pipeline
ST.PIERRE- JOLYS,Manitoba,Canada,January27,2014(ENS)–A
TransCanadanaturalgaspipelinerupturedandexplodedearly
SaturdaymorninginanisolatedareanearthetownofOtterburne,
25kilometers(15miles)southofWinnipeg.Thepre-dawnpipeline
breakandresultingexplosionsentamassivefireballintothenight
sky.
(1994)[Explosion] a 36-inch TETCO natural gas transmission pipeline explodes in Edison,NJ
At2357hoursonMarch23,1994,a36-inchTexasEasternTransmissionCorporation
(TETCO)naturalgastransmissionpipeline,operatingat975psi,catastrophicallyruptured
inEdisonTownship,NewJersey,initiatingafireeventofenormousmagnitude,thelargest
fireincidentevertooccurinMiddlesexCounty.The80-foot-longruptureinthepipe
occurredonpropertyoccupiedbytheQualityMaterials,Inc.asphaltplantandrippeda
craterapproximately100feetlong,50feetwide,and40feetdeep.

15. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 15
Natural Gas Transmission –Failure Categorization
CharacteristicsofthePipelineFailure:
Pinhole/Crack:thediameteroftheholeissmallerthatorequalto2cm.
Hole:thediameteroftheholeislargerthan2cmandsmallerthanorequaltothe
diameterofthepipe.
Rupture:thediameteroftheholeislargerthanthepipelinediameter.
TheInitialCausesofIncident:
ExternalInterference
Corrosion
ConstructionDefect/MaterialFailure
HotTapmadebyError
GroundMovement
Otherandunknown
Source: EGIG Report

16. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 16
Natural Gas Transmission –Primary Failure Reason
Source: EGIG Report
External
Interference
Digging, Piling,
ground works etc.
Achor, bulldozwer,
excavator etc.
Casing, sleeves
etc.
Corrosion
External
Internal
Others
Construction
Defect
Construction or
material
Welding defects
etc.
Failure of
component
Ground
Movement
Dike Break,
erosion, flood
Landslide
Mining & others
Other
Lightning
Maintenance etc.

17. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 17
Calculation of Hazard Distances & Thermal Radiation
ExampleofestimatedFailureScenariosforNaturalGasPipelinediameter42”
atlinepressure80Kg/cm2.
(NR–NotReached)
Location
Release of
Gas
(Kg/Sec)
Distances for different Thermal
Radiation (KW/m2) intensity and 3D
weather condition.
LFL distance (m)
for 3D weather
condition.
4.5 12.5 37.5
Case 1 –5 mm Diameter Hole (A/G) 0.29 9 8 NR 5
Case 1 –5 mm Diameter Hole (U/G) 9 5 NR 3
Case 2 –20 mm Diameter Hole (A/G)4.56 39 32 26 29
Case 2 –20 mm Diameter Hole (U/G) 32 19 NR 10
Case 3 –50 mm Diameter Hole (A/G)28.51 90 70 54 89
Case 3 –50 mm Diameter Hole (U/G) 75 47 NR 24
Case 4 –20% CSA (U/G) 2519 577 390 NR 211

18. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 18
Calculation of Hazard Distances & Thermal Radiation
ExampleofestimatedFailureScenariosforNaturalGasPipelinediameter42”
atlinepressure80Kg/cm2.
Location
Release of
Gas
(Kg/Sec)
Distances for different Thermal
Radiation (KW/m2) intensity and 3D
weather condition.
LFL distance (m)
for 3D weather
condition.
4.5 12.5 37.5
Case 2 –20 mm Diameter Hole (A/G)4.56 39 32 26 29
Location of gas leakage and fire
26 M distance of heat radiation of 37.5 KW/m2
32 M distance of heat radiation of 12.5 KW/m2
39 M distance of heat radiation of 4.5 KW/m2
Radiation Level (kW/m
2
) Observed Effect
37.5 Sufficient to cause damage to process equipment
12.5 Minimum energy required for piloted ignition of wood, melting of plastic tubing
4
Sufficient to cause pain to personnel if unable to reach cover within 20s; however blistering of the skin (second
degree burns) is likely; 0: lethality

19. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 19
Statistics of Gas Transmission Pipeline Incident -EGIG
In1982sixEuropeangastransmissionsystemoperatorstooktheinitiativeto
gatherthedataontheunintentionalreleaseofgasintheirtransmission
pipelinesystemknownasEGIG(EuropeanGasPipelineIncidentDataGroup).
EGIGhasmaintainedtheEuropeanGasPipelineIncidentDatabaseoffifteen
EuropeanCountriesonmorethan135000KMofpipelineseveryyear.
Thestatisticsofincidentscollectedinthedatabasegivereliablefailure
frequencies.Theoverallincidentfrequencyisequalto0.35incidentsperyear
per1000Kmovertheperiod1970to2010.

20. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 20
Source: EGIG Report
Statistics of Gas Transmission Pipeline Incident -EGIG
0.17
0.057 0.059
0.017
0.026
0.057
0.04
0.031
0.011 0.015
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
Primary Failure Frequency (1970-2011) per 1000 KM/Yr.
Primary Failure Frequency of 5 Year Moving Average per 1000 KM/Yr.
48.4
16.1
16.7
4.8
7.4
6.6
0 20 40 60
External Interference
Corrosion
Construction …
Hap tap made by error
Ground Movement
Other and Unknown
Primary Failure Cause Disribution (%)
External Interference
Corrosion
Construction
Defect/Material Failure
Hap tap made by error
Ground Movement
83%
13%
4%
Corrosion Distribution (%)
External
Internal
Unknown
41.3
16.5
15.6
7.5
1.6
17.5
Incident Distribution on Detection
Public/Land Owner
Patrol
Contractor
Company Staff
Online Inspection
Others

21. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 21
Statistics of Cross Country Pipeline Incidents -OISD
0
2
4
6
8
10
12
04-0505-0606-0707-0808-09
3
5
11
4
8
2
4
3
1
3
Nos. of Incident (including Fire Incident)
Nos. of Fire Incident
10%
3%
13%
10%
10%
19%
35%
Probable Causes
Pipeline Rupture
Fall from Height
Electrical related
Pipeline Maint./Repair
Corrosion
Construction
3rd Party Damage
Source: Analysis of Major Incidents in Oil & Gas
Industry 2004-2009 by OISD

22. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 22
Framework –Safety in Natural Gas Pipeline in India
Construction, Operation & Maintenance of Natural Gas
Pipeline System
PNGRB
(Technical& Safety
StandardofNaturalGas
Pipelines)
OISD
(Standard226–Natural
GasTransmissionPipeline
andCityGasDistribution
Network)
ASME 31.8
(GasTransmissionand
Distribution Piping
Systems)

23. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 23
Applicable Statutory Compliances
PetroleumandNaturalGasRegulatoryBoard(PNGRB)Act’2006.
GuidelinesforEnvironmentalclearanceofnewprojects–1981
TheEnvironment(Protection)Act-1986
Water(Prevention&ControlofPollution)Act1974
Air(Prevention&ControlofPollution)Act1981
ThePetroleumandMineralPipelines(AcquisitionofRightofUsersinLand)
Act,1962.
Manufacture,Storage&ImportofHazardouschemicalRules-1989
NationalHighwayAct,1956
RailwaysAct,1989

24. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 24
Safety Aspects of NG Pipelines -Construction
National&InternationalStandardslikeOISD,PNGRB,IS,ASME31.8B,API
etc.arebeingfollowedduringdesign,construction,operation&
maintenance.

Properlayout&interdistanceoffacilitiesaremaintainedasperOISDStd.
226&PNGRBRegulations.
Sizingofpipelinewallthicknessaccordingtothepopulationdensityofthe
area,designpressure,specifiedminimumyieldstrength,diameterofthepipe
longitudinaljointfactorandtemperaturede-ratingfactorasperANSI/ASME
B31.8.
Additionalcorrosionallowanceofminimum2mmofdesignwallthickness
considering30yearspipelinedesignlifeandmoderatecorrosionrate.

25. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 25
Safety Aspects of NG Pipelines -Construction
SN Locations Minimum Cover
(In Mtr)
i)Areaofagricultural,horticulturalactivity,
limitedornohumanactivity,industrial
commercialandresidentialarea
1.0
ii)Rockyterrain 1.0
iii)Drainage,ditchesatroads/railwaycrossing 1.0
iv)Minorrivercrossings/canal/drain/nala/ditches 1.5
v)Majorrivercrossing(belowscourlevel) 2.5
vi)Riverwithrockybed(belowscourlevel) 1.5
vii) Areaunderinfluenceoftides 1.5
viii)Cased/Uncasedroadcrossing 1.2
ix)Casedrailwaycrossing 1.7
PipelineCover :

26. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 26
Safety Aspects of NG Pipelines -Construction
Azone,400mwide,shallbeconsideredalongthepipelineroutewiththepipelineinthecentre-line
ofthiszone.Thentheentirerouteofthepipelineshallbedividedintorandomlengthsof1600m
suchthattheindividuallengthswillincludethemaximumnumberofbuildingsintendedforhuman
occupancy.Thenumberofsuchdwellingswhichareintendedofhumanoccupancywithineach1600
mzoneshallbecounted.
LocationClass1–ALocationClass1isany1600msectionthathas10orfewerdwellingsintendedforhuman
occupancy.ThisLocationClassisintendedtoreflectareassuchaswastelands,deserts,mountains,grazinglands,
farmlandsandothersparselypopulatedareas.
LocationClass2–ALocationClass2isany1600msectionthathasmorethan10butlessthan46dwellings
intendedforhumanoccupancy.LocationClas2isintendedtoreflectareaswheredegreeofpopulationisbetween
locationClass1andLocationClass3suchasfringeareasaroundcitiesandtowns,industrialareas,ranchorcountry
estates,etc.
LocationClass3–ALocationClass3isany1600msectionthathas46ormoredwellingsintendedforhuman
occupancyexceptwhenaClass4Locationprevailsandisintendedtoreflectareassuchassuburbanhousing
developments,shoppingcenters,residentialareas,industrialareas,andotherpopulatedareasnotmeeting
LocationClass4requirements.
LocationClass4–ALocationClass4includeareaswheremulti-storeybuildingsareprevalent,andwheretrafficis
heavyordenseandwheretheremaybenumerousotherutilitiesunderground.Multi- storeymeansfourormore
floorsaboveground,includingthegroundfloorandirrespectiveofdepthofbasementornumberoffloorsof
basement.
LocationClass:

27. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 27
Safety Aspects of NG Pipelines -Construction
Pipelinehaving3layerpolyethyleneexternalcoating.
Installationofremotelyoperatedsectionalizingvalvesatregularintervalsof
approximate8-32KMbasedonLocationClass.
ProvisionofIntermediatepiggingstationsatthedistanceofapproximate90
KMalongwiththepipelineroutetomeetthepiggingrequirementof
pipelines.
ProvisionofslugcatchermadeatCompressorStationtocollectthe
impurities,ifany.
PressuresafetyvalvesattheIntermediatePiggingStationsprovidedtotake
careofexcesspressure.

28. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 28
Safety Aspects of NG Pipelines -Construction
Installationofcasingpipesatallrailwaycrossingandhighwaycrossingas
perInternationalStandards.
Pipelinemarkerslikewarningboards,kilometer/aerialmarkersorboundary
pillarsalongthepipelineroute.
OpenPathGasDetectionSystematPipelineInstallationsarea.
Automaticfiredetectionandsuitablefireextinguishingsystemisinstalledat
allInstallations.
CathodicProtectionSystemprovidedforpipelineagainstcorrosion.
Corrosionsensingprobesformonitoringexternalcorrosionrate.

29. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 29
Safety Aspects of NG Pipelines -Construction
ProvisionofSCADAtoensureeffectiveandreliablecontrol,managementand
supervisionofthepipeline.
ProvisionofElectricalEquipmentbasedonAreaClassification.
EnvironmentalconsiderationbasedonEnvironmentalImpactAssessment
(EIA)&andRiskAnalysis(RA)studyforthepipelineandstationsbefore
constructionofpipeline.

30. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 30
Safety Aspects of NG Pipelines –Operation & Maintenance
Health,SafetyandEnvironmentManagementSystem
•HSEPolicyStatement&objectivestoensureimplementationofthepolicy
•SetofdetailedprocessessupportingeachactivityoftheHSEmanagementsystem.
•DevelopmentofOperationandMaintenanceProcedures
•Implementationofcontrolandmonitoringactivities
•Periodic,monitoring,reviewandreportingofperformance
•ComplianceAudit-ExternalandInternalSafetyAudit
•AccidentReportingsystem
•EmergencyManagementSystemtosafelyhandleemergencieswithminimalrisk(ERDMP).
•HazardIdentificationProcessessuchasHAZOP
•RiskAnalysisandRiskAssessmentProcesssuchasQRA
•WorkPermitSystemtoensureworkiscarriedoutinsafemanner.
•StructuredTrainingSystemforO&Memployeesincludingcontractworkers,securityetc.
•DevelopmentofManagementofChangeprocedurestoidentifyandconsidertheimpactof
changestopipelinesystemsandtheirintegrity.

31. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 31
Safety Aspects of NG Pipelines –Operation & Maintenance
DeploymentofcomprehensiveOperationandMaintenanceProceduresfor
ControlSystemandSafetyInterlocks.
OperatingProceduresmainlyincludes:
•SystemDescription
•Operationsetpoints
•Initialstartup
•Normaloperations
•Normalshutdownprocedure
•Temporaryoperations
•Executionofemergencyshutdowninasafe&timelymanner
•Emergencyshutdown
•Conditionsunderwhichemergencyshutdownisrequired
•Emergencyoperations
Developmentofdetailedmaintenanceprocedureforentirepipelinesystem
consideringthemanufacturer’srecommendationsandstipulatedStandards
OISD/PNGRB.

32. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 32
Safety Aspects of NG Pipelines –Operation & Maintenance

33. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 33
Safety Aspects of NG Pipelines –Operation & Maintenance
EstablishmentofNationalandRegionalGasManagementCentresaspartof
holisticmonitoringandcontrolofpipelinesystem. Itconsistsof
•Monitoringofoverallpipelinesandinstallations
•MaintainingPipelineHydraulicstomeetcustomerrequirement
•ControlonRemoteOperatedValvesofPipelineInstallations
•Managementofparameterdeviationoralarm,ifany
•
HealthinessofFireProtectionSystemofInstallations
Formationofintegritymanagementprogramframeworktoensurecontinual
/periodicassessment.Anevaluationprocesstomeasureeffectivenessofthe
currenthealthofthepipelineandtopreventanyfailuresinfuture.

34. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 34
Gas Management Centres-GAIL
NGMC
RGMC
AGRA-F’BAD
RGMC
NCR
RGMC
GUJ.
RGMC
AP
RGMC
TN
RGMC
TRIPURA
RGMC
MAH
RealtimedataofallPipeline
Parameters,SupplyandDelivery
ConditionsatallSourcesandMajor
CustomerterminalsthroughSCADA
Instant leak detection
with the help of Remote
Terminal Units (RTUs)

35. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 35
Safety Aspects of NG Pipelines –Operation & Maintenance
RightofWayforInspectionandMaintenance:
•RoadandHighwayCrossing–Onceina3months.
•RiverCrossing–Twiceinayear(BeforeandafterMonsoon)

36. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 36
Safety Aspects of NG Pipelines –Operation & Maintenance
PipelinePatrolling:
•GroundPatrolling–Onceinamonth
•FootPatrolling–LinewalkbyCompanyOfficialtwiceinyear(Beforeandafter
Monsoon)
View of Arial Patrolling of Pipelines

37. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 37
Safety Aspects of NG Pipelines –Operation & Maintenance
PipelinePigging:
•PiggingActivitiesforWetGas–Onceinayear
•PiggingActivitiesforDryGas–Onceina3years
IntelligentPipelinePiggingtobecarriedoutonceina10yearsanddata
mustbecomparedwithdataobtainedduringGeometricPiggingbefore
commissioningtoensurehealthofpipelines.
Intelligent Pigging of Pipelines

38. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 38
Safety Aspects of NG Pipelines –Operation & Maintenance
InspectionofCathodicProtectionSystem:
•PSP(PipetoSoilPotential)atfeedingpoint–Onceinafortnight
•PSPReadingatTestLeadPointallalongthePipeline–Onceina3months
•CathodicProtectionRectifier–Onceina2months
CoatingSurvey:
•PearsonSurvey/DirectCurrentVoltagegradient(DCVG)/ContinuousPotential
Logging(CPL)survey/CurrentAttenuationTest(CAT)oncein5yearstoensure
thehealthinessofpipelinecoating.

39. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 39
Safety Aspects of NG Pipelines –Operation & Maintenance
Awareness:
•DisplayofDo’s&Don’ts
•Conductingacomprehensivepublicawarenessprogramforconsumersandgeneral
public.TheeducationalmaterialtobepreparedinlocalHindiandEnglishlanguage.
Localaudiovisualmediaavailableshouldbeusedforsucheducationalprograms.

40. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 40
Safety Aspects of NG Pipelines –Operation & Maintenance
FireProtectionSystem:
•Installationofgasdetectionsystemequippedwithaudioandvisualalarm.
•ProvisionofIR/Smokedetectorsincontrolroom,MCC,utilityroomand
compressorenclosurewithprovisionofindication,alarmandannunciation.
•InstallationofElectricoperatedfiresirenswithaudiblerangeof1kmand/or
hootersofF&Gsystemaudiblewithinthecompressorstationpremises.
•Installationofmanualcallpointsatstrategiclocations.
•Manualoperatedfiresirenshallalsobeprovidedatstrategiclocations.
•ProvisionofFireFightingEquipmentatCompressorStations,Intermediate
PiggingStation,SectionalValveStations,GasEntry/Exitterminalsand
MeteringStations.
•ProvisionofWindsockonanappropriatelyelevatedstructurelikethecontrol
room/fire-waterpumphouseinsuchamannersoastoavoidblindareas.

41. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 41
Safety Aspects of NG Pipelines –Operation & Maintenance
FireProtectionSystem:
•AdequatecommunicatesystematallintermediatestationsincludingIP
stations/Repeaterstation.
•
TheFirewatersystemshallbeprovidedatcompressorstationsconsistingof:
a.Firewaterstorage
b.FirewaterPumps(MainandJockey)
c.Firewaterdistributionpipingnetwork
d.Firehydrant/Monitors
e.Watersprinkler/delugesystem.
•Firewatersystemshouldbedesignedtofighttwomajorfiressimultaneously
anywhereintheinstallationanddesignedonthebasisthatthecityfirewater
supplyisnotavailableclosetotheinstallation.
•
Waterrequirementforfirefightingtobemetthroughwaterstoragetanks. The
effectivecapacityofthetanksabovethelevelofsuctionpointshouldbe
minimum4hoursaggregatecapacityofthepumps.

42. “Conference on Chemical (Industrial) Disaster Management- Bangalore” 42
TheintegrityofNaturalGasPipelineSystemisachievedthrough
continuouseffortsatallstagestoensurethatpipelineis
designed,commissioned,operatedandmaintainedasper
stipulatedcodes,standardsandguidelines.
Continualtechnologicalup-gradationinoperation,inspectionand
maintenanceenhancesthesafetyofpipelinesystemand
increasesoverallsafetytogreatextent.