811
1 INTRODUCTION
Morethan twenty years havepassed since Hutchins
portrayed the distributed cognition of a maritime
operation(1995a).Byobservingtheenvironmentand
elicitingknowledge,hisresearchhasgainedinsightto
operations which previously was restricted to the
individuals involved. Subsequently, the distributed
cognition approach has been utilized to
analyze the
situational awareness of complex collaborative
environments (Artman & Garbis, 1998, Nazir et al.,
2015).MorerecentlytheDSAapproachhasportrayed
theawareness of more complex maritime operations
bytheuseofactivatedinformationelements(Stanton,
2014;2006,Sharma&Nazir,2017).
Notwithstanding the above developments,
operations in some specialized maritime segments
such as subsea survey operations remain to be
understoodingreaterdetail.Eventhoughthesekinds
ofoperationsincludeseveralteamsworkingtogether
with complex technology, relatively less research is
available for the context. As a multibillion industry,
the potential for
an accident concerning a subsea
Distributed Situation Awareness in a Demanding
Maritime Operation: A Case Study of the Subsea
Segment
E.Norstein,A.Sharma,S.Jungefeldt&S.Nazir
UniversityofSouth‐EasternNorway,Borre,Norway
ABSTRACT:Maritime subsea operations have increasedsignificantly in sizeand complexity during the last
decades as a result of the advances inthe offshore oil industry. Despite the fact that subsea operations can
involve hundreds of personnel, working together with complex technology, limited research
can be found
regardingtheoperationsintheavailableliterature.Thisstudyaimstoanalyzearoutinesubseaoperationusing
theDistributedSituationAwareness(DSA)frameworkandunderstandhowtheoperatorsonboardmaintain
their DSA in routine operations through a case study. In order to understand how the operation
unfold in
complexsociotechnicalsystemsandhowsituationalawareness(SA)isdistributedacrossagentsandartefacts,
thetheoreticalframeworkofDSAcanbeusefulasthefocusisontheinteractionsatasystemiclevel.Toachieve
theresearchobjectives,acombinationofqualitativemethodswasutilizedtoillustrateDSAon
boardasubsea
vessel.Initiallyanobservationwasconductedduringalivesubseasurveyoperationtocapturetheinteraction
between personnel and instruments. Furthermore, all observed personnel were subjected to retrospective
interviews to elicit further knowledge of the operation. Finally, the data was analyzed according to the
propositionalnetworkapproach
andHierarchicalTaskAnalysis(HTA).TheresultofthisstudyportraystheSA
ofasubseasurveyoperationaspropositionalnetworksforthemainphasesidentifiedintheHTA.Themain
findingsofthestudyshowasignificantlydifferenceinDSAamongtheBridgepersonnelandpersonnellocated
in the Online
Control Room (ONCR). Furthermore, it was found that the dynamic of the system allowed
personneltohavedifferentlevelofDSAwithoutjeopardizingtheoveralloperation.Finally,thesummaryof
thefindingsprovidesabasicunderstandingofhowaroutinesubseasurveyoperationunfolds.
http://www.transnav.eu
the International Journal
on Marine Navigation
and Safety of Sea Transportation
Volume 13
Number 4
December 2019
DOI:10.12716/1001.13.04.14
812
vessel could be of major consequences. In addition,
the consequences in case of accidents could be fatal
forthepersonnelonboard.
By analyzing the distribution of SA during a
subseaoperationitispossibletoportraytheoperation
atthesystemlevel.Thus,analyzingthesystemitself
to identify
flow of information and/or facilitation of
operations. Furthermore, the elaboration of
informationelementsusedduringtheoperationmay
prove beneficial in training and evaluation of
personnelinvolvedinsubseaoperations.Basedonthe
limitedresearchrelatedtooperationsinthisfield,this
articleaimstoexploreandanalyzeacomplex
subsea
operationbyutilizingtheframeworkofDSA.
2 FIELDSTUDY
AfieldobservationwasconductedfromSeptemberto
October 2017 on board a subsea vessel operating in
theNorthSea.Asthepurposeoftheresearchwasto
analyze collaborative interaction in a complex
operation,itwasfoundbeneficialto
observeasubsea
operation in a demanding scenario. Such complex
interactions can be best understood via naturalistic
observation (1995a). For the above reason, a field
studywasconductedonboardasubseavesselinits
natural setting. The subsea operation chosen for the
scenario was a pipeline survey, as this
kind of
operation requires collaboration of several teams on
board.WhiletheRemotelyOperatedVehicle(ROV)is
movingalongthepipelinesubsea,thevesselneedsto
follow at surface level. Consequently, the team
operating the ROV needs to collaborate with the
Bridgeteam.Furthermore,themainpurposeforsuch
ascenario
istocollectsurvey dataofthepipelineand
the subsea environment, which requires the
involvementofadditionalpersonnelwithspecialized
competence. The collaboration between all these
personnelandtechnologicalagentsworkingtogether
toachieveasinglegoalfitsthepurposeofacomplex
subsea operation. In addition, the pipeline
survey
chosenfortheobservationwasconductedinitsfinal
phasewherethevesselapproachestheendma nifold
located in an area clustered with pipes and subsea
assets.Moreover,theobservationwasperformedina
time‐period where marginal weather condition was
forecasted,generatinganadditionalchallengeforthe
teammembers.
2.1 Observationenvironment
Thesubseasurveyoperationobservedwasconducted
near the UK coast of the North Sea which is
considered a challenging environment for maritime
operations globally. To avoid theassets coming into
contact with fishing trawling equipment or other
hazards,themanifoldisoperatedwitha500msafety
zonegovernedbyaFloatingProductionStorageand
Offloading (FPSO) vessel anchored in the area. The
bridgeofficersonboardwereactivelycommunicating
with the FPSO and required a permission before
enteringthe500mzone.Presentonthefieldwasalso
astandbyboatworkingintheFPSOsvicinity.During
the initial
phase of the observation, the weather
conditions were moderate with about 30knots wind
and an estimated significant wave height of 2,5m
which is considered ma rginal weather for a subsea
survey operation. In addition, the weather was
forecasted to increase significantly the next hours.
MostactivitywasexpectedintheONCR
andBridge,
which therefore was the focus of this study and
subject to observation. In addition, communication
was observed from the Offline Control Room
(OFFCR)andtheFPSO.Anoverviewoftheobserved
agentsisillustratedinfigure1asanetworkstructure.
Figure 1 illustrate the network structure of the
personnel involved in the observed scenario. In
accordance with the DSA framework proposed by
Stanton et al. (2006), the involved personnel can be
seen as agents in a larger system. Thus, illustrating
the agent’s ability to have different but compatible
view of the situation through communication. The
majority of agents
were located in the ONCR and
wereallwithinverbal communication rangeof each
other.
Figure1NetworkstructureinSubseavessel.
As expected, most communication occurred
betweentheseparties.However,agentslocatedinthe
OFFCR were also directly involved in some of the
observed phases. Second to the ONCR, most
communication occurred on the Bridge between the
DPO and OOW. These agents also communicated
directlywiththeONCRbyanonlineintercom
system
andexternallywiththeFPSO,utilizingtheVHF.
The observation was conducted on board a
modern subsea vessel of newer construction and
which was commissioned recently. At the time of
observation,atotalof50persons were on board the
vesselcontributingtotheoperationindifferentways.
However,
only a few of the personnel were directly
involved in the scenario and were subjects to the
observation.Amongthese,themajoritywaslocatedin
theONCR which canbe considered the heart of the
operation. The online personnel are limited to the
most essential positions directly involved in the
operation
such as the ROV Pilots (RP), Inspection
Engineer (IE), Survey engineer (SE) and Cathode
Protectionengineer(CP).Inaddition,otherpersonnel
arelocatedintheadjacentOFFCR,whichisseparated
tominimizedisturbance. The layout of the observed
controlroomisillustratedinFigure2.
813
Figure2illustratesthelayoutoftheenvironment
observedduringthescenariowiththeactuallocation
ofparticipants.TheROVPilotandROVCo‐pilot(RC)
are sitting beside each other at the ROV operator
station, maneuvering the ROV subsea according to
theROVSupervisor(RS)andengineer’sinstructions.
Due
to the design of the ONCR all the participants
were within verbal communication range of each
other and could therefore communicate directly. In
addition,eachstationwasequippedwithaparty‐line
intercom system linked to the OFFCR, Bridge and
otherstrategicpositionsaroundthevessel.
Figure2.ControlroomlayoutinSubseavessel
Furthermore, the Bridge team consisting of the
Officer on Watch (OOW) and Dynamic Positioning
Operator (DPO) were also observed during the
scenario. While being physically separated from the
ONCR,theBridgeteamarestillcollaboratingclosely
with the online personnel with regards to vessel
movements.Tocollectadequatedataandavoid
ROV
damage,itisofvitalimportancethatthevesselmoves
alongthepipelineataspecificdistanceandspeedset
by the ONCR. Consequently, the DPO is following
the instructions communicated from the online
personnel and maneuverers the vessel accordingly
through the Dynamic Positioning (DP) system. For
thisreason,
theDPstationwaspresumedasacentral
locationinthenetworkandthereforeafocuspointof
the observation. In addition, the bridge team is
responsibleforthenavigationofthevesselandcanin
that respect reject any request from the ONCR that
compromisesthesafetyofthevessel.
2.2 Observation
Since the research aims to uncover the DSA in the
selected scenario by following the propositional
networkmethodology,informationelementsmustbe
identified. This can be done through the analysis of
verbal transcription, while the frequency of events
and interaction among the agents are observed
(Salmon et al.,
2009). Consequently, an observation
schedule was developed for the observed scenario.
Furthermore,theschedulewasdevelopedtoanevent
logasdisplayedintable1.
Table1.Abstractfromobservationschedule
_______________________________________________
Time Output Input Information/Activity
_______________________________________________
13:00:54 RS DPO Bridge–Quasar,canyougive
meanupdateoftheweather
please?
13:01:02 DPO RS Yeah,thewindisgustingto
30knotsnow,directionsouth
east
13:01:11 RS DPO What’sthewaveheight?
13:01:23 DPO RS Around2‐2,5mIwouldsay
13:01:27 RS DPO
 Roger
_______________________________________________
Tocapturethesocialcontext,thetimewaslogged
forwhen informationwas sent and received. As the
time was captured more accurately by audio
recorders it was necessary to identify the agent that
transmitted and received the information.
Consequently, the observation schedule included an
output and input section for the
observer to log the
agentsinvolvedasillustratedinTable1.
Furthermore, the main section of the observation
schedule concerned what kind of information
elementsthatwaspassedandreceived.Theobserver
was instructed to write the information exchanged
verbally, by radio and hand gestures. In addition,
other relevant activities
or tasks observed were
writtendownascommentsontheobservationlog.It
was recognized that the task of transcribing verbal
communication directly may be difficult in a
collaborativeenvironment.However,audiorecorders
were positioned on strategic places during the
scenario which simplified the transcribing. Further
attention was therefore given to
capture what the
audiorecorderscouldnotcapture.
After the observations performed on the bridge
and in the ONCR, these where transcribed into an
eventlog.Theeventlogwasconstructedbothbased
on the transcriptions from the recordings, but also
through the field notes constructed during the
observations. The
final event log contains the exact
times of the agent’s actions and communications, as
wellasinteractionswithartifacts(Artman&Garbis,
1998;Hutchins,1995a,1995b;Stantonetal.,2006).
2.3 HierarchicalTaskAnalysis
To enable the portrayal of the DSA, an HTA was
conductedwherethescenariowasdescribedthrough
itsgoalsandtasks.TheHTAwasinitiallyconducted
to consider “what should happen” in the scenario
(Stanton, 2006, p. 56). Further on, this was altered
after the observation, and then presented to the
Subject matter experts (SME´s) during the Critical
decisionmethod(CDM)interviews,touncover“what
actually
happens” (Stanton, 2006, p. 56). In this study
theoverall goal of thetask was toconductasubsea
pipelinesurvey.Subsequentlythesub‐goalsrequired
to reach this overall goal were determined. Finally,
the last step was to decompose the sub‐goals even
further (Stanton, Baber, & Harris, 2008).
After
establishing the goals and sub‐goals ina
decomposition level, an HTA plan was constructed.
Stanton et al. (2008) advises that the plan not
814
necessarilyneedstobelinear,butcanbedesignedin
avarietyofwaysaspresentedinTable2.
Table2.HTAplans(AdaptedfromStantonetal.,2008)
_______________________________________________
PlanExample
_______________________________________________
LinearDo1then2then3
Non‐linear Do1,2and3inanyorder
Simultaneous Do1,then2and3atthesametime
Branching Do1,ifXpresentthendo2then3,
ifXisnotpresentthenEXIT
CyclicalDo1then
2then3andrepeatuntilX
Selection Do1then2or3
_______________________________________________
2.4 CDMinterviews
CDM interviews were conducted after the
observationtoeliminatepossiblemisunderstandings.
The CDM was developed to extract knowledge and
thereby achieve a greater understanding of a real
world scenario (Hoffman, Crandall, & Shadbolt,
1998). The interview procedure for this study was
constructedaftertheobservation,based on
Hoffman
et al. (1998). Adopted to suit the chosen HTA,
observation and CDM combination approach. The
structure of the CDM interviews was based on
O`Hare,Wiggins,Williams,andWong(2000)probes.
Furthermore,thedesignatedprobesweremodifiedto
fit the specific objectives of this research (Stanton et
al.,2008).These
probeswereutilizedinacombination
withtheCDMframeworkasaninterviewguide.
FollowingtheDSAapproach(Stantonetal.,2006),
acontentanalysiswasconductedtoextractkeywords
representinginformationelements.Subsequently,the
text in the event log and the CDM transcripts was
brokendown to smallercomponents.
Thiswas done
in accordance with the DSA framework, where the
aim was to separate the content words from the
functionwords(Stantonetal.,2006).
2.5 Propositionalnetwork
A propositional network is constructed to highlight
the information elements distributed in a system
(Salmon, Stanton, & Walker, 2009). Salmon et
al.
(2009)definesapropositionalnetworkas;“a network
depictingtheinformationunderlyingasystem´sawareness
and the relationships between the different pieces of
information” (Salmon et al., 2009, p. 60) The
information elements are illustrated as nodes
connectedtoeachotherthroughdifferenttaxonomies
(Salmon et al., 2009; Stanton
et al., 2008). The
commonly used taxonomy is; has, is, are, causes,
knows, needs, requires and prevents (Stanton et al.,
2008). Consequently, these taxonomies were utilized
inthisstudy.
Thepropositionalnetworkwasconstructedbased
on information elements extracted in the content
analysis of the transcribed CDMinterviews (Salmon
et
al., 2009). These were also compared with the
observationeventlogtoincreasethereliabilityofthe
study.Additionally,duringthefinalizingoftheHTA
andthecontentanalysis,twooftheauthorsanalyzed
thedata.Afterwardsacomparisonwasmade,where
onlythesamegoalsandcontentwordswereutilized
to increase the reliability of the findings. The HTA
wasthenutilizedtopresentapropositional network
for each of the four main tasks; Identification,
Navigation,PositioningandDatacollection,whichwere
found during the finalizing of the HTA.
Subsequently,thedifferentnodesarethenshadedto
portraytheir
usageinthedesignatedtasks(Salmonet
al.,2009).
2.6 Populationandsample
Thisstudyaimstorepresentasystemrepresentative
forthemajorityofsubseavessels.Itwasthereforeof
interest to interview participants with experience
from other subsea vessels to verify the
generalizabilityofthestudy.
To portray
the operationsfrom different
viewpoints, all the informants were observed and
interviewedinrelationtotheirpositioninthesystem.
Thiswasfoundnecessaryassomeoftheinformant’s
switchedrolesduringthescenario.Thiswasthecase
for the OOW stepping in as DPO, and ROV
supervisor acting as an
ROV Pilot in some of the
phases.Toavoidconflictingdata,theinformantswere
requested to portray their (D)SA in accordance with
theircurrentpositionatthetimeofobservation.Table
3 presents the informants which were subjects to
observationandretrospectiveinterviews.
Table3. Informants subjected to observation and CDM
interview
_______________________________________________
ParticipantsTypeDatacollection
_______________________________________________
No.1‐ROVSupervisor Facetoface Observation&CDM
No.2‐ROVPilotFacetoface Observation&CDM
No.3‐ROVCoPilot Facetoface Observation&CDM
No.4‐SurveyEngineer Facetoface Observation&CDM
No.5‐Insp.Engineer Facetoface Observation&CDM
No.6‐CPEngineerFaceto
face Observation&CDM
No.7‐DPOFacetoface Observation&CDM
No.8‐OOWFacetoface Observation&CDM
_______________________________________________
3 RESULTS
Numerous activities and task were observed during
thescenarioandextractedfromtheCDMinterviews.
Afteranalyzingthedataseveraltimesincooperation
withSMEsafinalHTAwasdeveloped.Subsequently
thesetaskswereusedtodividethescenariointothe
following four phases: Identification, Navigation,
Positioningand
DataCollection.
815
Figure3.Phasesofthe observedscenario
The phases of the subsea pipeline survey are
illustrated as a process in Figure 3. During the
scenariotheprocesswasconductedseveraltimesand
was also aborted at different phases. In addition,
severalofthephases was sometimes conducted in a
different order and can therefore not be seen as
a
completely linear process. However, the figure is
sufficient for the purpose of providing a simplistic
viewofthiscomplexoperation.
3.1 Propositionalnetwork
Each of the four main phases identified in the HTA
were utilized to construct propositional network
diagrams, illustrating the activation of information
elements as shaded nodes
for the specific phase.
Figures 4 to 7 illustrate various phases and
corresponding information elements used. It is
recognizedthatseveraloftheinformationelementsin
the system are utilized in connection with other
phases. However, for illustration purposes, only the
informationelementsexplicitly linked tothe specific
phase are highlighted.
Finally, the propositional
networks in figure 8 & 9 illustrates the DSA at the
department level by activation of the information
elementsutilizedbytheagentslocatedintheONCR
andBridge.
The identification phase was chosen as the first
stepofthepipeline surveyprocessasthenavigation
phase
cannot commence before the destination
positionisknown.Thepropositionalnetworkforthe
identification phase in figure 4 highlights that the
activated information elements is restricted to the
agents in the ONCR. More specifically between the
RS,RP, RC and IE. Thismustbe seen inconnection
withthepurposeof
theidentificationtaskwhichisto
identify the subsea pipeline. Consequently, none of
theagentsonthebridgeweredirectlyinvolvedinthis
task.
Furthermore,thenavigationofthevesselandROV
needstobeplanned.Thisphaseincludesbothsubsea
navigation and ship navigation at surface level. The
information
elementsutilizedinthenavigationphase
isillustratedinfigure5andshowsalargepartofthe
systemisactivated.WhiletheROVteamisconcerned
with subsea objects, the agents on the bridge were
observed to consider other factors such as vessel
traffic. In addition, environmental conditions were
considered
in this phase as an integrated part of
navigation.
The propositional network in figure 6 illustrates
theDSAduringthepositioningphasewhichincludes
the maneuvering of the vessel and ROV, as well as
other interaction between operators and machinery
such as operating the tether winch, camera booms
and manipulators.
The DPO and ROV pilot was
observedtobekeyagentsduringthis phase asthey
areperformingthemaneuvering.Inaddition,theco‐
pilotwasobservedtohaveanactiveroleinassisting
the ROV pilot during maneuvering. A common
feature found with both operator stations is the
automated systems
that assist the maneuvering.
WhilethevesseliscontrolledbyafullyautomatedDP
system, the ROV has optional automated features
suchasheading,depthandaltitude.
Finally, when the ROV is positioned at the
identified pipeline the data collection commences
which is the overall purpose of a subsea pipeline
survey. The propositional network of the data
collection phase in figure 7 shows less activated
information elements then the other phases. This
must be seen in connection with the decision of
isolatingtheinformationelementstothosewhichhas
an explicit role regarding data collection. Thus, not
shading information elements that
led to the actual
data collection as they are activated in previous
phases. Moreover, the agents directly involved in
collectingdatais restricted to afewof the agents in
the overall system. Hence, IE for eventing, SE for
multibeam data and CP for collecting CP data. In
addition,the
RCwasobservedtohaveadirectrolein
eventing as he adjusts the cameras according to the
IEsinstructions.
816
Figure4.Knowledgeactivationofagents duringtheIdentificationphase
817
Figure5.Knowledgeactivationofagents duringtheNavigationphase
818
Figure6.Knowledgeactivationofagents duringthePositioningphase
819
Figure7.Knowledgeactivationofagents duringtheDatacollectionphase
820
Figure8.Knowledgeactivationofagents intheONCR
821
Figure9.Knowledgeactivationofagents ontheBridge
822
4 CONCLUSION
TheaimofthisstudywastodescribeDSAinasubsea
operation. Therefore, an observation was conducted
on board a subsea vessel during a live operation in
the North Sea. Afterwards, CDM interviews were
performed with all participants following the DSA
framework.TheDSAofthesubsea
surveyoperation
was described through a combination of HTA,
observation transcripts, interview citation and
propositional network. These altogether provided a
basicunderstandingofDSAduringasubseapipeline
survey. Moreover, it was found conducive to utilize
thedesignatedmethodinsuchanunknown,complex
anddynamicscenario.
Primarily the results
show that the SA is
distributed locally within the distinct departments
between agents and artefacts. Moreover, most DSA
wasfoundtooccuramongagentsinvolvedinsimilar
tasks, such as the RP & RC. Furthermore, it was
uncoveredthatmostinformationdistributedbetween
the Bridge and ONCR concerned the sub tasks
of
Navigation, more specifically, regarding vessel
positionmovesandenvironmentalconditions.
4.1 Contributionoftheresearch
This study explored the specialized subsea segment
whichstillisconsideraminor butimportantpartof
the maritime industry. As two thirds of the earth is
covered by water and the developments in
the
maritime industry with the aim to explore areas
farther offshore, subsea operations are expected to
increaseinthefuture.Consequently,itcanbeargued
that this study contributes to creating a platform to
explore the dynamic and complex subsea survey
operations by describing DSA in different phases.
Finally, the study
provides a framework that allows
researchers to explore the segment even further for
systemdesignandtrainingpurposes.
4.2 Futureresearch
Limitedresearch exists regarding DSA in the subsea
segment. Due to the generalizability of the results
within the specific segment, this study provides a
frameworkforfutureresearchto
buildon.Thefuture
research directions can benefit from analyzing
operations in complex and demanding operations
such as above and with the greater understanding
related to the roles assigned to different agents and
the system design can be optimized for the same.
Thus, opening for the utilization of the same
methodology
in a great variety of maritime
operations.
While this study focused on a few key agents
involved in subsea pipeline survey, other subsea
operations can be considered even more complex as
they include far more people and artefacts. Such an
operation could be subsea construction which adds
the subsea crane
interaction to the system. In
addition,suchoperationscanincludeseveralvessels
and ROVs operating in close vicinity while
collaborating to achieve their common goal. By
adaptingthemethodologyutilizedinthisresearchthe
DSA of such operations could be analysed at the
system level. Moreover, it could highlight the
strengths
and weaknesses of the system that
ultimately can lead to improving the safety and
efficiencyoftheoperation.
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