Ship Safety Assessment

The assessment of ship safety has become an increasingly important issue. The techniques of risk and cost-benefit assessments are used in the ship-safety decision-making process. The approach is called a formal safety assessment (FSA) and is composed of the following five steps [17]  

A hazard is defined as a physical situation with the potential for human injury, damage to property, damage to the surrounding environment, or some combination of these. 

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The proposed method called SSAMADC (Ship Safety Assessment Method in Abnormal/Damage Conditions) is a risk-based method and is connected with application of the quantitative risk assessment QRA approach. The method is an alternative method of safety assessment of ships in abnormal/ damage conditions in comparison with the method included within the SOLAS 2009 regulations. 

In practice using the proposed concept of a risk-based decision support system for the ship safety assessment in damaged conditions the following major steps are necessary to be done ... 

The method presented in the paper called as the SSADC (Ship Safety Assessment in Damage Conditions) method is a risk-based method. It is based on assessment of the ship performance and risk assessment. It enables to quantify the risk and use it a measure of a ship safety. The method is of non-prescriptive character. It may be treated as a prescriptive method form the formal point of view if the structure of requirements in the form of any known regulations are used. 

Chapter 9 presents various important aspects of airline and ship safety, including U.S. airline-related fatalities and accident rates, aircraft accidents during flight phases and causes of airline crashes, world airline accident analysis, air safety-related regulatory bodies and their responsibilities, aviation recording and reporting systems, noteworthy marine accidents, ship safety assessment, and ship port-related hazards. 

Spouge J. (1997) Risk Criteria for Use in Ship Safety Assessment. Report of the DNV Technica UK, the Institute of Marine Engineers, UK. 

Address the issues in formal ship safety assessment. 

Chapter 4 describes both the offshore safety case approach and formal safety assessment of ships. The current practices and the latest development in safety assessment in both the marine and offshore industries are described. The relationship between the offshore safety case approach and formal ship safety assessment is described and discussed. The study of risk criteria in marine and offshore safety assessment is carried out. The recommendations on further work required are finally given. 

Chapter 11 concludes the book by summarising the results and outlining the contributions to formal ship safety assessment. 

The safety analysis techniques described in this book will facilitate ship safety assessment in various situations. They ean be tailored for safety analysis of any maritime and offshore engineering product with domain-specific knowledge. As some of these approaches described are subjective in nature, they may be more applicable for many engineering applications that lack reliable failure data. 

A formal ship safety assessment framework proposed by the UK MCA consists of the following five steps ... 

Software safety analysis is another area where further study is required. In recent years, advances in computer technology have been increasingly used to fulfil control tasks to reduce human error and to provide operators with a better working environment in ships. This has resulted in the development of more and more software intensive systems. However, the utilisation of software in control system has introduced new failure modes and created problems in the development of safety-critical systems. The DCR-1996 has dealt with this issue in the UK offshore industry. In formal ship safety assessment, every safety-eritical system also needs to be investigated to make sure that it is impossible or extremely unlikely that its behaviour will lead to a catastrophic failure of the system and also to provide evidence for both the developers and the assessment authorities that the risk associated with the software is acceptable within the overall system risks (Wang (1997)). 

More test case studies also need to be carried out to evaluate and modify formal ship safety assessment and associated techniques and to provide more detailed guidelines for the employment of them. This would enable validation of them and can also direct the further development of flexible risk modelling and decision making techniques and facilitate the technology transfer to industries. 

Wang J., Pillay A., Wall A. and Ruxton T., (1999) The Latest Development in Ship Safety Assessment , Proceeding of the 4 International Conference on Reliability, Maintainability and Safety (ICRMS 99), Shanghai, China, May 18-21, pp. 711-719. 

Lack of reliable safety data and lack of confidence in safety assessment have been two major problems in safety analysis of various engineering activities. This is particularly true in FSA due to the fact that the level of uncertainty is high. In ship safety assessment it may often be difficult to quantify the probability of undesired events occurring and the associated consequences due to this very reason. 

FangQ,YangZ, HuS,WangJ. 2005 Formal safety assessment and application of the navigation simulators for preventing human error in ship operations. Journal of Maritime Science Applied 2005 4(3), Rotterdam Balkema... 

Fire safety assessment of hazardous material transporting ship using fire simulation... 

In this paper, a case study of using fire simulation for fire safety assessment of low level radioactive waste material transporting ship is presented. First, two different fire scenarios are developed from previous fire accidents statistics. Then fire simulation is carried out to evaluate the fire safety performance in each scenario. The main objective of the simulation is to evaluate the extent of damage to the cargo hold carrying hazardous materials due to temperature increase. 

Guema L. Pizywarty M. 2007. Probabilistic method of ships navigational safety assessment on large sea areas with consideration of oil spills possibility, International Probabilistic Symposium Ghent. 

The aim of the research is to work out a proposal of an alternative method of safety assessment of ships in damaged conditions. The research has been done because the method included in the SOLAS regulations does not cover certain type of ships. 

The method combines the ship performance-oriented approach with the risk-based approach, Gerigk (2010). The holistic approach to safety assessment is applied. An influence of design, operational, management-related and human factors on safety is taken into account. Then, the matrix type risk model is applied. This model has a holistic character. Next, it is possible to take into account almost all the possible scenarios of an accident. 

The proposed method may be used at any ship s life circle, including safety assessment of the ship during a catastrophe. Some elements of the method can be used for safety assessment of different means and systems of seaborne transportation. In the future the method can be useful in elaboration of a new methodology of safety assessment of ships, which bases on the application of risk analysis. 

The risk and safety assessment of ships in damaged conditions requires modeling of the risk contribution tree. For each hazard a separate event tree may be modeled using the Event Tree Analysis ETA. The basic event tree ETA for the safety assessment of ships in damaged conditions is presented in Figure 3. 

Figure 2. Structure of the method of risk and safety assessment of ships in damaged conditions.

An example of application of the ship performance data regarding the ship roll function in time domain and ALARP risk evaluation criteria for assessment of a ship safety in damage conditions is presented in Figure 8. The vertical axis in Figure 8 regards the angle of heel in degrees and the horizontal axis concerns the time in seconds. 

Gerigk, M., 2004. On a risk-based method for safety assessment of a ship in critical conditions at the preliminary design stage. Polish Maritime Research, 11(1 (39)), pp. 8-13. 

Gerigk, M.,2008. Modeling of hazards, consequences and risk for safety assessment of ships in damaged conditions in operation. (ESREL2008), 4, pp. 3303-3310. 

Gerigk M. 2010. A complex method for safety assessment of ships in damaged conditions using the risk assessment (D.Sc. thesis), Monography No. 101, Published by the Gdansk University of Technology (in Polish), Gdansk 2010. 

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