Safety and environmental risk and reliability modeling


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The vast resources of the world’s oceans need
to be fully utilized to benefit human activities
in a sustainable manner. The maritime
industry has made use of the ocean in a very
responsible way, but inland water resources
have been much more underutilized and under-
maintained, especially for transportation.
In an age so dire to find ways to mitigate the
challenge of climate change and its associated
impacts, recent research has indicated
that inland water transportation represents
the cleanest mode of transportation. This
indicates the potential for an increase in usage
of inland waterways for transportation.
The use of inland water transportation is
forecast to rise because of the potential for
short sea shipping, expanding deep-sea operations,
and alternative mitigation options for
climate change. Coastal water transportation
is associated with low probability, high
consequence accidents, which makes reliability
requirements for the design and operation
for safety and environmental protection very
necessary. Collision represents the largest
percentage of accident risk scenarios among
water transportation risk factors. This paper
discusses recent work in risk and reliabilitybased
design, and safe and efficient vessel
operation in coastal waters. This includes
systems based approach that covers proactive
risk as well as holistic, multiple-criteria
assessment of waterways variables required
to develop mitigation options and decision
support for preventive, protective and control
measures for various collision accident
scenarios within inland waterways.
Keywords: Inland transportation, accidents, risk assessment,
vessel safety, collisions, climate change,
marine pollution, navigation

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Safety and environmental risk and reliability modeling

  1. 1. J. of Marine Env. Eng., Vol. 9, pp. 145–173 © 2010 Old City Publishing, Inc. Reprints available directly from the publisher Published by license under the OCP Science imprint, Photocopying permitted by license only a member of the Old City Publishing Group Safety and Environmental Risk and Reliability Modeling Process for Sustainable Inland Water Transportation System O. Sulaiman 1 , * ab Saman Abd Kader 2 , A.H. Saharuddin 3 , W.B. Wan Nik 4 and K.B. Samo 5 1,3,4,5 University Malaysia Terengganu, 21030, Kuala Terengganu, Terengganu, Malaysia 2 University Technology Malaysia, Skudai 81310, Johor, Malaysia The vast resources of the world’s oceans need consequence accidents, which makes reliabil- to be fully utilized to benefit human activi- ity requirements for the design and operation ties in a sustainable manner. The maritime for safety and environmental protection very industry has made use of the ocean in a very necessary. Collision represents the largest responsible way, but inland water resources percentage of accident risk scenarios among have been much more underutilized and un- water transportation risk factors. This paper der-maintained, especially for transportation. discusses recent work in risk and reliability- In an age so dire to find ways to mitigate the based design, and safe and efficient vessel challenge of climate change and its associ- operation in coastal waters. This includes ated impacts, recent research has indicated systems based approach that covers proac- that inland water transportation represents tive risk as well as holistic, multiple-criteria the cleanest mode of transportation. This assessment of waterways variables required indicates the potential for an increase in us- to develop mitigation options and decision age of inland waterways for transportation. support for preventive, protective and con- The use of inland water transportation is trol measures for various collision accident forecast to rise because of the potential for scenarios within inland waterways. short sea shipping, expanding deep-sea opera- tions, and alternative mitigation options for Keywords: Inland transportation, accidents, risk as- climate change. Coastal water transporta- sessment, vessel safety, collisions, climate change, tion is associated with low probability, high marine pollution, navigation *Corresponding author: Tel: 60-9-668-3697; Fax: 60-9-668-3193; email: pp MB_37(Kader)2.indd 145 2/19/2010 11:04:20 AM
  2. 2. 146 Sulaiman et al. 1.0  Introduction This paper discusses risk and reliability model for the assessment and analysis of collision acci- Marine transportation services provide dent scenarios leading to design for the preven- substantial support to various human activi- tion, control of collisions and protection of the ties its importance has long been recognized. environment. The paper also discuss elements IMO cross boundary activities in maritime of the process that address requirement to op- regulation contain lessons learned that could timize design, existing practice, and facilitate be a model for the quest for today’s environ- decision support for policy accommodation for mental global regulatory bodies to meet cur- evolving coastal transportation regimes. rent environmental challenges and advance- ment of human civilization (SOLAS, 2004; 2.0 Risk and reliability modelling Cahill R.A., 1983; Cooke, R.M. 1997). Most requirement IMO regulatory works are not mandatory for coastal transportation. Except implemen- tation issues that are directed through flag In order to build reliable inland water states and port state control. The clear cut ad- transportation system, it is important to vantage of inland water transportation system understand the need analysis through ex- (IWTS) over other modes of transportation, amination of the components of system short sea service and evolving deep sea activi- functionality capability and standards re- ties are being driven by recent environmental quirement. These include major require- problems and dialogues over alternative re- ments and classification of coastal water newable ways of doing things. The criticality transportation system. Also important is of transportation operations within the coast- functionality capability like channel, ves- line and the prohibitive nature of the occur- sel, terminal, and other support systems. rence of accidents due to high consequence Environmental risk as well as ageing factors and losses have equally made it imperative related to design, operation, construction, and necessary to design sustainable, efficient maintenance, economic, social, and disposal and reliable coastal transportation systems. requirement for sustainable marine system This include consideration for holistic char- need to be critically analysed. Risk identifica- acteristics that of environmental aspects of tion work should be followed by risk analysis navigation channel, vessels and other water that include risk ranking, limit acceptability resources issues since a sustainable inland and generation of best options towards de- water system cannot stand alone. Waterway accidents fall under the scenarios of collision, fire and explosion, flooding, and grounding (Bottelberghs P.H., 1995; Murphy, D.M. & M.E. Paté-Cornell, 1996). Collision is caused by (see figure 1): i) loss of propulsion. ii) loss of navigation system. Figure 1 iii) other accident from the ship or waterways. Waterways risk by accident categories [11]. Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 146 2/19/2010 11:04:21 AM
  3. 3. Safety and Environmental Risk and Relibiality Modeling Process 147 velopment of safety and environmental risk assessments, which considered the relative mitigation and goal based objective for evalu- risks of different conditions and events. In the ation of the development of sustainable cost maritime industry, contemporary time risk as- effective inland water transportation that sessment has been instrumental to make reli- fall under new generation green technology able decisions related to prediction of flood, (Report of marine accident, 2009). Weigh- structural reliability, intact stability, collision, ing of deductive balancing work requirement grounding and fire safety. Probabilistic and for reliable and safe inland water transpor- stochastic risk assessment and concurrent use tation through iterative components of all of virtual reality simulation that consider the elements involved should include social, eco- broader impacts of events, conditions, sce- nomic, health, ecological and technological narios on geographical, temporal impacts, considerations. Other concerns are related risks of conditions is important for continu- to other uses of water resources and through ous system monitoring. Additionally, sensitiv- best practices of sediment disposal, mitiga- ity and contingency (what if) analyses can be tion for environmental impact, continuous selectively used as tools to deal with remnant management, monitoring, and compensation reliability and uncertainty that answer hidden for uncertainty as well as preparation for fu- questions in dynamic and complex systems. ture regulation beyond compliance policy or principles should be addressed. Risk assessment has been used by the 3.0 Benefits and limitations of using business community and government, and risk and reliability models safety cases of risk assessment have been used by United Kingdom (UK) health safe- ty and environment (HSE). In the maritime Rampant system failure and problems industry, risk assessment has been used for related to system failure have brought the vessel safety, marine structure, transportation need to adopt a new philosophy based on of liquefied natural gas (LNG) and offshore top down risk and life cycle model to design, platforms. In Europe maritime risk assess- operate and maintain systems based on risk ment has been used for coastal port risk anal- and reliability. Likewise, election of alterna- yses and pilot fatigue. International Mari- tive ways to mitigate challenges of safety and time Organization (IMO) and United States environmental risk of system deserve holistic, Coast Guard (USCG) rule making have issued reliability analysis approaches that provide guidelines and procedures for risk based deci- the following benefits: sion making, analysis and management under formal safety assessment (Report of marine i. flexibility and redundancy for innovative, accident, 2009; Cooke, R.M. 1997; Det Nor- alternative improvised design and concept ske Veritas, 2004). Risk analysis when used development for rulemaking is called Formal Safety Assess- ii. evaluation of risk reduction measure and ment (FSA), while when it is used for compli- transparency of decision making process ance is addressed as Quantitative Risk Analy- iii. systematic tool to study complex problem sis (QRA). Contemporary time has seen risk iv. interaction between discipline assessment optimization using scenario based v. risk and impact valuation of system Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 147 2/19/2010 11:04:21 AM
  4. 4. 148 Sulaiman et al. vi. facilitate proactive approach for system, ed that most human product or waste ends safety, current design practice and man- their ways in the estuarine, seas and finally to agement the ocean. Chemical contamination and litter vii. facilitate holistic touching on contributing can be observed from the tropics to the poles factor in system work and from beaches to abyssal depths. But the viii. systematic rule making, limit acceptability conditions in the marine environment vary and policy making development widely. The open sea is still considerably clean ix. analysis of transportation system in contrast to inland waters. However, time continue to see that the sea is being affected The dynamic distributive condition, long in- by man almost everywhere and encroach- cumbent period and complexity of marine sys- ment on coastal areas continues worldwide, tem comes with limited oversight that make the if unchecked. This trend will lead to global process of identification and addressing human deterioration in the quality and productivity as well as organizational error difficult. This of the marine environment (Murphy, D.M. includes checks and balances, redundancy, and M.E. Paté-Cornell, 1996). training more complicated. Inherit drawbacks This shows the extent and various ways hu- associated with risk and reliability model are man activities and uses water resources affect (SOLAS, 2006; SOLAS, 2006): the ecological and chemical status of water- ways system. Occurrence of accident within i. lacks of historical data (frequency, proba- the coastline is quite prohibitive due to unim- bility, expert judgment) aginable consequences and effects to coastal ii. linking system functionality with standards habitats. Recent environmental performance requirement during analysis (total safety studies on transportation mode has revealed level vs. individual risk level, calculation of that transportation by water provides wide current safety level) advantages in term of less, low Green House iii. risk indices and evaluation criteria (indi- Gas (GHG) release, large capacity, congestion, vidual risk acceptance criteria and sustain- development initiative etc. These advantages ability balance) tells about high prospect for potential modal iv. quantification of human error and uncer- shift of transportation and future extensive tainty use of inland water marine transportation The complexity associated with human and where risk based system will be necessary to organization factors requires human reliability provide efficient, sustainable and reliability assessment and uncertainty analysis to be mod- safe clean waterways as well as conservation elled independently. of environment. This equally shows that increase in human activities will have potential effects in coastal and marine environment, from population 4.0 Marine pollution risk pressure, increasing demands for space, com- petition over resources, and poor economic A group of experts on the scientific aspects performances that can reciprocally undermine of marine pollution comment on the condi- the sustainable use of our ocean and coastal tion of the marine environment in 1989, stat- areas. Different forms of pollutants and ac- Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 148 2/19/2010 11:04:21 AM
  5. 5. Safety and Environmental Risk and Relibiality Modeling Process 149 tivities that affect the quality of water, air and rine systems are dynamic system that have soil as well as coastal ecosystems are: potential for high impact accidents which are predominately associated with equip- i. Water: pollution release directly or washed ment failure, external events, human error, down through ground water; economic, system complexity, environmen- ii. Air pollution: noise population, vibration; tal and reliability issues. This call for inno- iii. Soil: dredge disposal and contaminated vative methods, tools to assess operational sediments. issue, extreme accidental and catastrophic iv. Flood risk: biochemical reaction of pollu- scenarios. Such method should be extensive tion elements with water; use to integration assessment of human ele- v. Collision: operational; ment, technology, policy, science and agen- vi. Bio diversification: endangered and threat- cies to minimise damage to the environment. ened species, and habitat; Risk based design entails the systematic risk analysis in the design process targeting risk Main sources of marine pollution: prevention and reduction as a design objec- tive. They should be integrated with design i. Point form pollution: toxic contaminants, environment to facilitate and support sustain- marine debris and dumping. able approach to ship and waterways design ii. Nonpoint form pollution: sewage, alien need. Thus, enabling appropriate trade offs species, and watershed Issues. on advance decision making that consider size, speed, novelty, type and technology lead- Main sources from ships are in form of: ing to optimal design solutions (Det Norske Veritas, 2004) (see figure 2). i. Operational: operational activities along Integrated risk based system design re- the shipping routes discharging waters quires the availability of tools to predict the contaminated with chemicals (whether safety performance and system components intentionally or unintentionally). as well as integration and hybridization of ii. Accidental risk: Collision due to loss of safety and environmental factors, lifecycle propulsion or control. phases and methods. It is important to de- velop, refine, verify, validate through effec- Risk associated with environmental issue in the tive methods and tools. Such integrative and context of ship, design has impacts related to shipping trends, channel design criteria, ship manoeuvrability and ship controllability. Risk based regulation risk based operation risk based design 5.0 Modelling the risk and reliability Total risk concept Risk based method components of complex and dynamic system Technolohgy element Environmetal elements Human element The consequence of maritime accident Figure 2 comes with environmental problem. Ma- Risk modelling process. Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 149 2/19/2010 11:04:21 AM
  6. 6. 150 Sulaiman et al. total risk tools require logical process with Frequency at which a potential undesirable holistic linkage between data, individual risk, event occurs is expressed as events per unit societal, organizational, system description, time, often per year. Upon establishing under- conventional laws, principle for system design standing of whole system from baseline data and operation need to be incorporated in the that include elements of channel and vessel risk process. Verification and employment of dimensioning shown in figure 3, the frequency system based approach in risk analysis should can be determined from historical data. How- be followed with creation of database and ever, it is quite inherent that event that does identification of novel technologies required not happen often attracts severe consequence for implementation. Unwanted event which and lack data. Such event is better analysed remain the central front of risk fight is an through probabilistic and stochastic model occurrence that has associated undesirable hybrid with first principle and use whatever outcome which range from trivial to cata- data is available (Kite-Powell, H.L., D. Jin, N. strophic. Depending on conditions and solu- M. Patrikalis, J. Jebsen, V. Papakonstantinou, tion based technique in risk and reliability 1996). Incidents are unwanted events that work, the model should be designed to pro- may or may not result to accidents if necessary tect investment, properties, citizens, natural measure is taken according to magnitude of resources and the institution which has to event and required speed of response. While, function in sustainable manner within ac- accidents are unwanted events that have either ceptable risk. immediate or delayed consequences. Immedi- The risk and reliability modeling process ate consequences variables include injuries, begins with definition of risk which stands loss of life, property damage and persons in for the measure of the frequency and sever- peril. Point form consequences variables in- ity of consequence of an unwanted event. clude further loss of life, environmental dam- Figure 3 Channel and vessel dimension. Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 150 2/19/2010 11:04:21 AM
  7. 7. Safety and Environmental Risk and Relibiality Modeling Process 151 age, and financial costs. System risk can be c. Situation causal factor: Number of estimated through equation 1. participants time/planning, volatility environmental factors, congestion, Risk (R) = Probability (P) time of day risk associated with sys- X Consequence (C) (1) tem can be based on. d. Organization causal factor: Organi- The earlier stage of the risk and reliability proc- zation type, regulatory environment, ess involves finding cause of risk, level of impact, organizational age management type/ destination and putting a barrier by all means changes, system redundancy, system in the pathway of source, cause and victim. Risk incident/accident history, individual, and reliability process targets the following: team training and safety management system. i. Risk analysis and reduction process: This involves analytic work through selective To deal with difficulties of risk migration marine deterministic and probabilistic method system (complex and dynamic by nature), reli- that assures reliability in the system. Reduc- ability assessment models can be used to capture tion process will target initial risk reduc- the system complex issues as well as patterns of tion at design stage, risk reduction after risk migration. Historical analyses of system design in operation and separate analysis performance is important to establish perform- for residual risk for uncertainty and human ance benchmarks in the system and to identify reliability. Risk in complex systems can patterns of triggering events which may require have its roots in a number of factors rang- long periods of time to develop and detect (Emi ing from performance, technology, human H., et al., 1997). Likewise, assessments of the error as well as organizational cultures, all role of human/organizational error and their of which may support risk taking or fail to impact on levels of risk in the system are critical sufficiently encourage risk aversion. in distributed, large-scale systems. This however ii. Cause of risk and risk assessment: this imposes associated physical oversight linked to involve system description, identifying the uncertainty during system design. Effective risk risk associated with the system, assessing assessments required three elements: them and organizing them according to degree of occurrence and impact in matrix i. Framework form. Causes of risk can take many ways ii. Models including the following: iii. Process a. Root cause: Inadequate operator know­edge, skills or abilities, or the l 5.1  Risk Framework lack of a safety management system in an organization. Risk framework provides system descrip- b. Immediate cause: Failure to apply tion, risk identification, criticality, ranking, basic knowledge, skills, or abilities, impact, possible mitigation and high level or an operator impaired by drugs or objective to provide system with what will alcohol. make it reliable. The framework development Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 151 2/19/2010 11:04:22 AM
  8. 8. 152 Sulaiman et al. involves risk identification which requires analysis, reassessment of machinery, equip- developing a structure for understanding the ment, and personnel can be helpful in as- manner in which accidents, their initiating sessing the utility of different risk reduction events and their consequences occur. This measures. Figures 4 and 5 show the risk com- includes assessment of representative system ponents, system functionality and regulatory and all linkages that are associated to the requirement for reliability model that can be system functionality and regulatory impact. followed for each risk scenario. 5.2  Models 5.3  Processes The challenges of risk and reliability meth- The process should be developed to provide od for complex and dynamic systems like ship effective and sound risk analysis where ac- motion at sea require reliable risk models. curacy, balance information that meets high Risk mitigation measures can be tested and scientific standards of measurement can be the trade off between different measures or used as input. This requires getting the science combinations of measures can be evaluated. right and getting the right science by target- Changes in the levels of risk in the system ing interests of stakeholders including port, can be assessed under different scenarios and waterway community, public officials, regula- incorporating “what if” analyses in different tors and scientists. Transparency, community risk mitigation measures. Performance trend participation is additional input to the risk Figure 4 Risk model. Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 152 2/19/2010 11:04:22 AM
  9. 9. Safety and Environmental Risk and Relibiality Modeling Process 153 High level Goal Assessment / Safety and environmental protection objective Tier -Standards Requirement 12 - Functional Requirement Goal Analysis criteria compliance of verification Goal based Tier 3 IMO instruments/ Classification rules, industrial standards Tier 4 Class guides, technical procedure process Design process Approval Secondary standards for company or individual ships - Code of practice, safety and quality systems Tier 5 shipbuilding, operation maintenance and manning Figure 5 High level goal based assessment. process; checks the plausibility of assump- al analysis (system linkage), expert analysis tions could help ask the right questions of the (expert rating) and organizational analysis science. Figure 6 and 7 show the risk process (Community participation). diagram. (See appendix 1 for process log) Table 1 shows models that have been used Total integrated risk can be represented by: in the design system based on risks. IMO and Sirkar et al (1997) methods lack assessment Rt = f (Re, Rs, Rh) (2) of the likelihood of the event. Other mod- els lack employment of stochastic method Where: Re (environment) = f (sensitivity, advert whose result may cover uncertainties associ- weather…), Rs (ship) = f (structural and system ated with dynamic and complex components reliability, ship layout and cargo arrangement…), of channel, ship failure and causal factors Rh (crew) = f (qualification, fatigue, etc. ) like navigational equipment, better training Holistic and integrated risk based method and traffic control (Guedes Soares, C., A.P. combined various techniques in a process Teixeira, 2001; Emi, H. et al., 1997). There- as depicted in Figure 8, this can be applied fore, combination of stochastic, statistical, for each level of risk for system in question. reliability and probabilistic together with Each level is complimented by applying caus- hybrid employment of goal based, formal Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 153 2/19/2010 11:04:22 AM
  10. 10. 154 Sulaiman et al. Figure 6 Holistic Risk analysis Process. Figure 7 Holistic Risk analysis Process. safety assessment methods and fuzzy multi and reliable design product for complex and criteria network method that use historical dynamic systems. The general hypothesis be- data of waterways, vessel environmental and hind assessing physical risk model of ship traffic data could yield efficient, sustainable in waterways is that the probability of an Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 154 2/19/2010 11:04:23 AM
  11. 11. Safety and Environmental Risk and Relibiality Modeling Process 155 Figure 8 Total risk concept. Table 1 Previous risk work. Model Application Drawback Brown et al (1996) Environmental performance of tankers (Sirkar et al (1997)) Consequences of collisions and groundings difficulties on quantifying consequence metrics Brown and Amrozowicz Hybrid use of risk assessment, probabilistic simulation Oil spill assessment limited to use and oil spill consequence assessment model of fault tre Sirkar et al (1997) Monte Carlo technique to estimate damage + spill cost Lack of cost data analysis for environmental damage IMO (IMO 13F 1995) Pollution prevention index from probability distributions Lack (Sirkar et al (1997)). rational damage and oil spill. Research Council Alternative rational approach to measuring impact of Lack employment of stochastic Committee (1999) oil spills probabilistic methods Prince William Sound, The most complete risk assessment Lack of logical risk assessment Alaska, (PWS (1996)) framework (NRC (1998)) (Volpe National Accident probabilities using statistics and expert opinion. Lack employment of stochastic Transportation Centre methods (1997)). Puget Sound Area Simulation or on expert opinion for cost Clean up cost and environmental (USCG (1999)). benefit analysis damage omission accident on a particular transit depends on Risk and reliability modeling involves haz- a set of risk variables which required to be ard identification, risk screening, broadly analyzed for necessary conclusion of pro- focused, narrowly focused and detailed Anal- spective reliable design. ysis, Table 2 shows iterative method that can Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 155 2/19/2010 11:04:24 AM
  12. 12. 156 Sulaiman et al. Table 2 Process table. Process Suitable techniques HAZID HAZOP, What if analysis, FMEA, FMECA Risk analysis FTA, ETA Risk evaluation Influence diagram, decision analysis Risk control option Regulatory, economic, environmental and function elements matching and iteration Cost benefit analysis ICAF, Net Benefit Human reliability Simulation/ Probabilistic Uncertainty Simulation/probabilistic Risk Monitoring Simulation/ probabilistic be incorporated for various needs and stages ii. Fact analysis for check of consistency of of the process. accident history iii. Conclusion on causation and contributing factor iv. Countermeasures and recommendations 6.0 Accident analysis for prevention of accident Accident and incident need to be prevented The process is followed by probability and as the consequence could result to compro- stochastic calculation analysis of cause and mise to safety leading to unforgettable losses frequency model where value of each node and environmental catastrophic. Past engi- extracted from data according to operational neering work has involved dealing with acci- situation are used in system modeling. The dent issues in reactive manner. System failure process is then followed by severity calcula- and unbearable environmental problems call tion analysis of consequence model where the for new proactive ways that account for eq- probability for each branch and the value of uity requirement for human, technology and end state (severity) is fetched from modelled environment interaction in the system. The database. accidental categories and potential failure in waterways is shown in figures 9. Figure collision contributory factors modeled from 6.1  Collision Scenario RELEX software. The whole process starts with system de- Collision is the structural impact between scription, functionality, regulatory determina- two ships or one ship and a floating or still tion and this is followed with analysis of: objects that could result to damage. Collision is considered infrequent accident occurrence i. Fact gathering for understanding of con- whose consequence in economical, environ- tribution factor mental and social terms can be significant. Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 156 2/19/2010 11:04:24 AM
  13. 13. Safety and Environmental Risk and Relibiality Modeling Process 157 Figure 9 Accident scenario. Figure 10 Collision contributing factors modelled from RELEX software. Prevention of collision damages is likely to drifting towards objects also need to be ac- be more cost-effective than mitigation of counted for. The collision model scenario its consequences. Probabilistic predictions also involves data characteristic of hull ar- can be enhanced by analysing operator ef- eas and environmental information; major fects, drifting and loss of power or propulsor contributing factors to collision are shown that take into account ship and waterway in Figure 11. systems, people and environment into con- Outcome of analysis is followed by suitable sideration. Other causative factors like the Risk Control Options (RCO), where itera- probability of disabled ship as function of tion of factual functionality and regulatory ship type, the probability of a disabled ship elements is checked with cost. The benefit Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 157 2/19/2010 11:04:24 AM
  14. 14. 158 Sulaiman et al. Human errors Failure on propulsion machinery and steering failure Causes of Ship Collision Environment Factor related to the ship Other factors related to accident Figure 11 Cause of collision. realised from safety, environmental protec- preceded by related events that can be detected tion and effect of the probability of high level and corrected by having underlying root causes of uncertainty associated with human and ranging from human errors, equipment fail- organizational contributing factor to risk ures, or external events. The result of frequency of collision are also important. The risk and consequence analysis is checked with risk process functions to determine and deduce acceptability index for industry of concerned. the idea for modest, efficient, sustainable Tables 3 and 4 show risk acceptability criteria and reliable system requirement and arrange- for maritime industry. The analysed influence ment (Parry, G., 1996; Pate Cornell, M.E., diagram deduced from the comparison can be 1996). Collision carried the highest statistic followed with cost control option using cost of in respect to ship accident and associated cau- averting fatality index or Imply Cost of Avert- sality. The consequences of collision are: ing Fatality (ICAF) and As Low as Reasonable Possible (ALARP) principle. i. The loss of human life, impacts on the economy, safety and health, or the envi- ronment; 6.2  Failure Modes Effect Analysis (FMEA) ii. The environmental impact, especially in the case where large tankers are involved. A Failure Modes Effect Analysis (FMEA) However, even minor spills from any kind is a powerful bottom up tool for total risk of merchant ship can form a threat to the environment; Table 3 iii. Financial consequences to local communi- Frequency risk acceptability criteria for maritime industry. ties close to the accident, the financial con- Frequency sequence to ship-owners, due to ship loss classes Quantification or penalties; Very unlikely once per 1000 year or more likely iv. Damage to coastal or off shore infrastruc- Remote once per 100- 100 year ture, for example collision with bridges. Occasional once per 10- 100 year Probable once per 1- 10 years Collision events are unplanned, always possi- Frequent more often than once per year ble, but effectively manageable and frequently Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 158 2/19/2010 11:04:24 AM
  15. 15. Safety and Environmental Risk and Relibiality Modeling Process 159 Table 4 Consequence risk acceptability criteria for maritime industry. Quantification Serenity Occurrence Detection RPN Current failure that can result to death failure, performance catastrophic 1 2 10 of mission Failure leading to degradation beyond accountable limit and critical 3 4 7 causing hazard Controllable failure leading to degradation beyond major 4 6 5 acceptable limit Nuisance failure that do not degrade system overall minor 7 8 2 performance beyond acceptable limit analysis. FMEA is probably the most com- iii. Listing  the effects of the failure mode: monly used for qualitative analysis and is also what does the failure mode mean to stake- the least complex. FMEA has been employed holders. in the following areas: iv. Rating severity of the effect : 1 being not severe at all and 10 being extremely i. The aerospace industry during the Apollo severe. missions in the 1960s. v. Identifying the causes of the failure mode ii. The US Navy in 1974 developed  a tool effect and rank the effects in the occur- which discussed the proper use of the tech- rence column: the scoring denotes how nique. likely this cause will occur. Score of 1 means it is highly unlikely to ever occur Today, FMEA is universally used by many dif- and 10 means we expect it to happen all ferent industries. There are three main types of the time. FMEA in use today: vi. Identifying the controls in place to detect the issue and rank its effectiveness in the detec- i. System FMEA: concept stage design sys- tion column: 1 would mean there are excel- tem and sub-system analysis. lent controls and 10 would mean there are ii. Design FMEA: product design analysis no controls or extremely weak controls. before release to manufacturers. iii. Process FMEA: manufacturing assembly It is strongly recommended that Serenity, Oc- process analysis. currence and Detection (SOD)for weak control should be noted. SOD numbers is multiplied Analyzing FMEA involves: and the value is stored in RPN (risk priority number) column. This is the key number that i. Listing key process steps in firm column will be used to identify where the team should for the highest ranked items risk matrix. focus first. If, for example, there is case with ii. Listing the potential failure mode for each severity of 10 (very severe), occurrence of 10 process step: how the process input could (happens all the time), and detection of 10 (can- go wrong. not detect it) RPN is 1000. This indicates a seri- Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 159 2/19/2010 11:04:24 AM
  16. 16. 160 Sulaiman et al. ous situation that requires immediate attention. where the graph falls, step for risk control The consequence could further be broken down option and sustainability balancing, cost ben- into effect for ship, human safety, oil spill, dam- efit effectiveness towards recommendation age, ecology, emission and other environmetal for efficient, reliable, sustainable decision impacts. Number 1–10 are assigned according can be taken. The frequency (F) of accidents to level of serenity. Risk priority number (RPN) involving consequence (N) or more fatali- for total serenity is determining as follows: ties may be established in similar ways as individual or societal risk criteria. For risks RPN = S X O X D (3) in the unacceptable/intolerable risk region, the risks should be reduced at any cost. Risk Matrix constructed from system and sub sys- 6.3  ALARP principal, risk acceptability tem level analysis can be deduced according criteria and risk control option to acceptability index defined according to table 5 and figure 12 to deduced measure Consequence thresholds priority of value of ALARP. Within ALARP range, Cost Ef- choice is awarded. The highest Consequence fectiveness Assessment (CEA) or Cost Ben- tripped in order of priority give the overall efit Analysis (CBA) shown in Figure 13 may consequence. Catastrophic: Descriptors of be used to select reasonably practicable risk catastrophic consequences for 1. People; 2. reduction measures. Infrastructure; 3. Values. Major: Descriptors of major consequences for 1. People; 2. In- frastructure; 3. Values. Moderate: Descriptors 7.0 Risk Analysis Considerations of moderate consequences for 1. People; 2. Infrastructure; 3. Values. Minor: Descriptors of minor consequences for 1. People; 2. Infra- In addition to a sound process, robust structure; 3. Values. Insignificant: Descriptors risk framework and eventual deductive risk of insignificant consequences for 1. People; model, there are other considerations that 2. Infrastructure; and 3. Values. should be factored into the design of an ef- Risk acceptability criteria establishment is fective risk model. These items include the use dynamic because of differences in environ- of available data, the need to address human ment, diversity in industries and choice of factors, areas of interest, stakeholder interest regulations requirement to limit the risk. Risk and approaches to treating uncertainty in risk is never acceptable, but the activity implying analysis. Data required for risk work should the risk may be acceptable due to benefits of involve information on traffic patterns, the safety reduced, fatality, injury, individual risk, environment (weather, sea conditions, and societal risk, environment and economy. Per- visibility), historical, current operational ception regarding acceptability is described performance data, and human performance by Green et al (1998). The rationality may data. The models intentions are highly de- be debated, societal risk criteria are used by pendent on appropriately selected databases increasing number of regulators. that accurately represent the local situation Figure 12 shows prescribed illustrative in- and the effectiveness of the models. However, fluence diagram by IMO. Based on region there is always issue of missing data or data Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 160 2/19/2010 11:04:25 AM
  17. 17. Safety and Environmental Risk and Relibiality Modeling Process 161 Figure 12 Influence diagram, ALARP = As Low As Reasonably Practicable: Risk level boundaries (Negligible/ALARP/Intolerable). Table 5 Risk matrix. costt Diferent between cost of polution control and environmetal damage Minimum sum of cost Cost of polution control High damage cost with no control No economic gain from polusion control Cost of damage from polution Minimum sum of cost Figure 13 Risk cost benefit and sustainability analysis curve. Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 161 2/19/2010 11:04:25 AM
  18. 18. 162 Sulaiman et al. limitations especially for complex system and scale systems with limited physical oversight. their low frequency, high consequence nature. Assessing the role of human and organiza- Therefore creative procedures are required tional performance on levels of risk in the to develop compensation for data relation- system is important, such error is often cited ships. The model could use probabilistic, as a primary contributor to accident, which stochastic, simulation and expert judgments end up leaving system with many more un- couple existing deterministic and historical known. Expert judgments and visual real- method for a reliable system analysis of de- ity simulation can be used to fill such un- sired design (M. Kok, H.L. Stipdonk, W.A. de certainty gaps and others like weather data. Vries, 1995; Stiehl, G.L., 1977). Even when attempts are made to minimize When insufficient local data is available, errors from expert judgments, the data are world wide data from other areas may be inherently subject to distortion and bias. With referred to (e.g., Europe, south and North an extensive list of required data, there are America). However, ones need to make as- limits that available data can place on the ac- sumptions about the similarity of operations curacy, completeness and uncertainty in the in the concerned area or elsewhere. This is to risk assessment results. Expert judgments give ensure how behaviour in one aspect of opera- prediction about the likelihood that failures tional (e.g., company management quality) that would occur in specific situations can parameter (e.g., loss of crew time) correlates be used to quantify human reliability input with another area (e.g., operations safety). in risk process. The data from other areas can be used as Uncertainty is always part of system behav- long as major parameters and environmen- iour. Two common uncertainties are: aleatory tal factors are compared and well matched. uncertainty (the randomness of the system Care is required with the use of worldwide itself) and epistemic uncertainty (the lack of data as much of those data are influenced knowledge about the system). Aleatory un- by locations or local environmental condi- certainty is represented by probability mod- tions (Skjong, R., 2002). Electronic access els while epistemic uncertainty is represented to worldwide casualty data such as the Paris by lack of knowledge concerning the param- MOU, U.K., Marine Accident Investigation eters of the model (Pate Cornell, M.E., 1996). Board (MAIB) and IMO Port State detention Aleatory uncertainty is critical, it can be ad- databases makes possible access to worldwide dressed through probabilistic risk analysis casualty statistics. Diligence should also be while epistemic uncertainty is critical to al- observed about the large number of small low meaningful decision making. Simulation scale, localized incidents that occur that are offers one of the best options to cover extreme not tracked by marine safety authorities, e.g case uncertainty besides probability. Evalua- small craft (not always registered or being tion and comparison of baseline scenario to able to be detected by VTS, AIS) accidents a set of scenarios of interest (tug escort) and in waterways. American Bureau of shipping operational circumstance including timelines (ABS) has begun an effort to identify precur- and roles can also be incorporated. Response sors or leading indicators of safety in marine Scenarios can also be analysed for things transportation. Human Factors modelling that can not be imagined or modeled to be should be considered for distributive, large accounted for in the simulator (especially real Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 162 2/19/2010 11:04:25 AM
  19. 19. Safety and Environmental Risk and Relibiality Modeling Process 163 time). A flexible critical path and slack analysis iv. Comparing the model behaviour applica- can be performed as input to the system simu- tion to other rivers of relative profile and lation and uncertainty analysis (Cahill (1983) vessel particular or comparison of improve- and Emi et al., (1997)). A safety culture ques- ment plan implemented like traffic separa- tionnaire which assesses organizational, vessel tion scheme (TSS). safety culture and climate can be administered v. Triangulating analysis of sum of probabil- to provide quantitative and qualitative input to ity of failure from subsystem level failure the safety culture and environmental percep- analysis. tion analysis for sustainable system design. vi. Plotting of lognormal, probability density cumulative and density function. 7.1  Between Reliability and Validation 8.0 Conclusion Further reliability work and validation of the risk analysis could be activated through the following: Following irreparable and economic loses from traditional reactive action against ac- i. Accident means, variance and standard cident and incessant system failure, institu- deviation from normal distribution tions are evolving with hybrid proactive top down and bottom up system based approach For 10 years =  Mean (µ) = 10 × Fc (4) that account for total risk associated with system lifecycle to protect the environment Variance (σ) = 10 × Fc × (1 - Fc), and prevent accident. Those that cannot be Standard deviation =  σ , Z = (X - µ)/σ (5) prevented and protected need or must be con- trolled under risk and reliability based design ii. Year for system to fail from binomial, mean / operability platform. time to failure and poison distribution. Development of novel method to address Poison distribution probability at N trial is each contributing factor to accident is very represented by: important. The potential for inland water is great and there is a need to implement IMO N Fr (N / γ, Τ) = e γ,Τ ( ) γ , ( γ ⋅ T) N! (6) rules model to mitigate accident risk. Colli- sion risk is much common and propulsion where y = Fc, T = time to fail failure, loss of navigation control and hu- man error are the sub system contributing iii. Binomial distribution – for event that factors. Preceding total risk qualitative sys- occurs with constant probability P on each tem description and hazard identification, trail, the likelihood of observing k event in probabilistic and stochastic process quanti- N trail is binomial distribution. tative analysis can be performed for system level analysis, while fault tree and event tree N L(K / N, P) =   P K (1 - P) N,K   P (7) quantitative analysis can be utilized to de-    termine risk index of the subsystem factors. Average number of occurrence is NP Interpretation of risk index into ALARP in- Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 163 2/19/2010 11:04:25 AM
  20. 20. 164 Sulaiman et al. fluence diagram can provide decision support of Experts on the Scientific Aspects of Marine Pollution. Blackwell Scientific Publications. London. information necessary for cost control option Cahill, R.A., 1983. Collisions and Their Causes. London, towards sustainable, reliable, efficient tech- England: Fairplay Publications. nology choice for system design and opera- Cooke, R.M., 1997. Uncertainty Modeling: Examples and Issues. tion. The cumulative results from qualitative Safety Science. 26:1, 49–60. analysis can be made more reliable through Det Norske Veritas, 2004. Thematic Network for Safety Assessment of Waterborne Transportation. Norway. iterative quantitative, scientific, stochastic Guedes Soares. C., A.P. Teixeira., 2001. Risk Assessment in and reliability analysis. These methods pro- Maritime Transportation. Reliability Engineering and vide valuable and effective decision support System Safety. 74:3, 299–309. tool for application of automated system Kite-Powell, H.L., D. Jin, N.M. Patrikalis, J. Jebsen, V. engineering analysis that facilitate inclusion Papakonstantinou, 1996. Formulation of a Model for Ship Transit Risk. MIT Sea Grant Technical Report. Cambridge of reliability, environmental protection and MA. 96–19. safety as part of the iterative design proc- Emi, H. et al., 1997. An Approach to Safety Assessment for Ship esses for new and innovative marine system Structures, ETA analysis of engineroom fire, Proceedings of ESREL ’97. International Conference on Safety and designs. Intelligently adoption of those proc- Reliability. Vol. 2. esses eventually can result to safer, efficient, Parry, G., 1996. The Characterization of Uncertainty in more reliable and sustainable system. Probabilistic Risk Assessments of Complex Systems Reliability Engineering and System Safety. 54:2-3. 119–126. Roeleven, D., M. Kok, H.L. Stipdonk, W.A. de Vries, 1995. Inland Waterway Transport: Modeling the Probabilities of REFERENCES Accidents. Safety Science. 19:2-3. 191–202. Skjong, R., 2002. Risk Acceptance Criteria: Current Proposals and IMO Position. Proceedings of the conference on Surface International Convention for the Safety of Life at Sea (SOLAS), Transport Technologies for Sustainable Development. 2004. International Maritime Organization (IMO). Edition, Valencia. Spain. Consolidated London. Stiehl, G.L., 1977. Prospects for Shipping Liquefied Natural Gas. Bottelberghs P.H., 1995. QRA in the Netherlands. Conference on Marine Technology. 14:4. 351–378. Safety Cases. IBC/DNV. London. N. Soares, C., A.P. Teixeira 2001. Risk Assessment in Maritime Report of marine accident, 2009. Transportation. Reliability Engineering and System Safety. maia/publications/report2003/causes.pdf, accessed in March. 74:3. 299–309. Skjong, R., Vanem, E. Endersen, O., 2005. Risk Evaluation Pate Cornell, M.E., 1996. Uncertainties in Risk Analysis: 6 Levels Criteria. SAFEDOR. 2005. Deliverable D.4.5.2 (Submitted of Treatment. Reliability Engineering and System Safety. to MSC 81 by Denmark). 54:2-3. 95–111. International Maritime Organisation (IMO). International Convention for the Safety of Life at Sea (SOLAS), 2006. (1974). Amendments. Chapter II-2, Part D, Reg. 13. Means of Escape. International Maritime Organisation (IMO). Amendments to the Guidelines for Formal Safety Assessment (FSA), 2006 for Use in the IMO Rule Making Process. MSC/ MEPC.2 / Circ 5 (MSC/Circ.1023 – MEPC/Circ.392). Murphy, D.M. M.E. Paté-Cornell., 1996. The SAM Framework. A Systems Analysis Approach to Modeling the Effects of Management on Human Behavior in Risk Analysis. Risk Analysis. 16:4. 501–515. GESAMP, 1990. The State of the Marine Environment, IMO/ FAO/UNESCO/ WMO/WHO/IAEA/UN/UNEP Joint Group Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 164 2/19/2010 11:04:26 AM
  21. 21. Safety and Environmental Risk and Relibiality Modeling Process 165 Appendix 1: Risk analysis process flow chart and Process log Step 1 Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 165 2/19/2010 11:04:26 AM
  22. 22. 166 Sulaiman et al. Step 1 S/N Activity Input Interacting sub- Critical issues Controls Controling Output Comment process measuremnet output 1 Input from Scope detail Making checklist Scope of - - Scope of problem from checklist research, relevant HAZARD definition according to rule IDENTIFI- regulation CATION process Stake holder Profile - Contribution, Qualification, Team structure. HAZID availability experience, facilitation planning round table scheduling Select recorder Data recording - Ability to capture Use of Monitoring of Selected recorder relevant inputs software, tape- records recording Obtain Casualty Root cause analysis Validity of the Input from Convergent character Assimilated data necessary statistic, data, of accident s and input data reputable of inputs information, expert input incidents databases data and relevant supporting experience documents Schedule ALL- Time for Selection Time for round Schedule organize meting engagement completion of of stand by table session distribute HAZID process, alternative material cost of meeting Barnstorming to Casualty What If , checklist, Environmental Evaluation of Divergent of input Identify accident identify accident statistic, data , FMEA, HAZOP, and stake holder inputs scenarios scenario using expert input RCA, Task Analysis attitude e.g. DELPHI, what- if / checklist, FMEA, HAZOP, RCA, Task Analysis Comprehensive? Accident Divergent - Classification of Decision scenario relevant of inputs inputs contribute of process Estimate Each accident FMEA, FTA (with Validity of result Validation with Variation from Frequency frequency: select scenarios HRA) reported data reported data estimate (F) appropriate experience technique e.g. FMEA, FTA ( with HRA) Estimate Each accident ETA, HAZOP, Validity of result Validation with Variation from Consequence consequence: scenarios WHAT-IF (with reported data reported data estimate (C) select HRA) experience appropriate technique e.g. ETA, HAZOP, WHAT-IF (with HRA) Classify and Accident - Establish Reported data % of generated Rank scenario rank hazards scenario(F risk matrix, and experience scenarios C) elimination of members of irrelevant scenario Summary / Accident - Reasoning on Documents Step one summary Output from result scenario(F ranking , clarity standards and presentation step 1 C) (IMO, IACS, PIANC, LUAS) Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 166 2/19/2010 11:04:26 AM
  23. 23. Safety and Environmental Risk and Relibiality Modeling Process 167 Step 2 Journal of Marine Environmental Engineering145-173 pp MB_37(Kader)2.indd 167 2/19/2010 11:04:27 AM