Monday, 12 November 2018
To widen the understanding of the risks in relation to intact stability 36 intact stability incidents at sea have been analysed. These incidents does not represent a complete list of incidents and therefore not intended to be used for calculating probabilities or frequencies. The list is used to highlight the different types of conditions and different stability failure modes that lead to an intact stability incident, the often severe consequences that follow with an intact stability incident, and the large variations in the operational conditions.
The aim is to discuss qualitative aspects of intact stability risk. Most of the incidents described are serious accidents, i.e., leading to one or more fatality, damage to the vessel that interrupt the service or vessel lost. The 36 incidents add up to more than 408 fatalities. The incidents described in Table 2 can all most often be contributed to a combination of causes and for many of the accidents the cause is uncertain.
Many of the incidents (approximately 20 out of 36) are cases were the operational condition and ship state was not according to design. For example, vessels that are over loaded and/or operated in heavy weather with hatches open potentially in combination with forces from fishing gear. Cargo shift is also common. These conditions lead to a poor recoverability after large heel angles.
For cargo vessels the cargo and ship status is generally changed under controlled circumstances (often at port). There is a potential for a high level of internal and external control. Therefore, a high level of detail in the data on the ship status is possible. On the other hand, vessels such as fishing vessels are an example of an operation where the ship status is changed at sea dynamically without external control which lead to large uncertainties.
This difference in potential control over the ship’s loading condition produce different conditions for safety work, different reliability of the passive safety designed into the craft, and different reliability as well as different need for operational safety measures. However, knowledge on safe operations, based on knowledge about the vessel’s limitations and weaknesses (edge awareness) could increase the reliability of the crew decisions taken on-board in relation to intact stability especially for ships and vessels that relatively often operate beyond the operational conditions defined during the design. Therefore, operational safety measures can be an effective approach to reach acceptable levels of safety, especially for operations with large uncertainties.
It is here argued that the conditions for operational measures differs between ship types as a result of different types of operations and different conditions for implementing the measures on-board. Therefore, it is here proposed that there is an important distinction between a ship’s general likelihood for intact stability incidents such as large roll motions (vulnerability to intact stability failures) and if the ship at a specific situation will not, when it experience an intact stability incident, return to a safe mode (recoverability after intact stability failures). Vulnerability is then typically a result of ship design whereas recoverability can be a result of ship design as well as operational aspects such as decisions taken on-board in relation to loading or unclosed hatches.
The safety introduced by design measures can deteriorate by lower control of ship condition (large uncertainties) and the resulting operations outside the design conditions.
The second-generation intact stability rules mainly investigate the vulnerability to intact stability failure for ships operating within the operational conditions. However, the ships recoverability to intact stability failure as well as other life saving measures need to be included if the safety effects of high vulnerability to intact stability failure is to be assessed. It is still not identified that high vulnerability alone is enough to introduce a safety problem according to IMOs definitions of.
Ships with high recoverability and high vulnerability includes for example modern PCTC with high possible control and specialized hull forms (that lead to vulnerability to specific intact stability failure modes) and superstructures that can contribute to high recoverability after large heel angles. For such ships high-end on-board simulations can be an effective way of supporting the master’s decisions about routing as well as manoeuvres to avoid intact stability incidents. However, as mentioned above, such on-board operational guidance is not necessarily needed to meet IMO’s safety level ambitions according to the FSA and should if that is the case not be mandatory. The operational safety measures are motivated by the aim to increase effectiveness and quality of service, i.e. with the aim to reduce injuries to personnel and damages to cargo during the incident. Suitable operational measures for these ships need to be ship specific and supported by support tools, i.e., operational guidance. Therefore, the exchange of stability knowledge between the design phase and the development of stability management support systems should be facilitated by the IMO rules.
For ships with high control and standard configuration standard operational safety measures is enough.
For ships with low recoverability and moderate to high vulnerability the uncertainty in relation to the effectiveness of engineering solutions is high (because the conditions defined during design cannot be assumed to be valid). The effective approach is most likely found in making sure that risk drivers, such as open hatches and overloading, are reduced, especially in situations when the ship is more vulnerable to intact stability incidents. In such situations decisions support, such as operational guidance, can be ineffective as a result of the limited possibility to take in the information presented by such support. Identifying and tending to risk drivers is a work that has to be performed by the whole crew by strengthening risk knowledge and risk awareness on-board thru safety management. Operational safety measures are a precondition for safe operations for this type of ships. Specific knowledge and risk management could be the primary choice for safety assurance (compare with the UK Safety Case approach for the offshore industry and the risk based approach for the Norwegian offshore industry).
A wider understanding of the terms for operational measures is needed, especially in relation to a ship’s recoverability after intact stability incidents. They cannot be judged in the same way as passive engineering solutions for safety. Such a view takes away the strength of safety solutions in the ship operation. However, the acceptable level of uncertainty varies between types of ships and especially with the ship’s recoverability after stability incidents.
Link to more info on the original article:
Tuesday, 30 October 2018
A ship is a good example of a socio-technical system where its behavior cannot be understood without a model description that covers both social and technical aspects.
Engineering approaches to improve safety are developed under the assumption that there is a link between the technical solutions implemented and the safety level during operation. There is also a link between how the ship is operated and the safety level during operation. However, this second link is often hidden to engineers because traditional engineering approaches and tools typically do not describe how risk decisions taken on-board affect safety. As discussed within the intact stability community operational guidance or limitations are an important aspect of a holistic safety approach for intact stability. However, such operational measures also introduce new uncertainties.
The work in regard to the second generation intact stability criteria is based on three alternative assessment procedures: Level 1 vulnerability assessment, Level 2 vulnerability assessment; and Direct stability assessment. Compliance with Level 1, 2 or the Direct stability assessment fulfils the requirements of the intact stability criteria. It is also proposed that alternatively, ship-specific operational limitations or operational guidance can be developed for conditions failing to fulfil the criteria.
The work within the second generation in-tact stability criteria so far has focused on “physic-based analysis” and “passive” safety measures described by the level 1 and 2 assessments. However, the operational environment and the operation itself is not static, this may lead to that safe passive design measures need to be far reaching in order to exclude unsafe operations.
When investigating 36 intact stability incidents they add up to more than 408 fatalities. The median number of persons on-board is 14 and the median number of fatalities per accident is 3 (13 and 6 respectively if the ship capsized or sunk). In all but 11 cases the ship was lost as a result of the accident. The incidents can all most often be contributed to a combination of causes and for many of the accidents the cause is uncertain.
Many of the incidents, approximately 20 out of 36, are cases were the operational condition and ship state was not according to design. For example, vessels that are over loaded and/or operated in heavy weather with hatches open potentially in combination with forces from fishing gear. Cargo shift is also common. These conditions lead to a poor recoverability after large heel angles. Therefore, in the investigated incidents there are many aspects that a physics based approach that only consider the operational conditions to a limited number of standard situations will not capture.
For example, does the difference in potential control over the ship’s loading condition produce different conditions for safety work, different reliability of the passive safety designed into the craft, and different reliability as well as different need for operational safety measures. However, knowledge on safe operations, based on knowledge about the vessel’s limitations and weaknesses (edge awareness) could increase the reliability of the crew decisions taken on-board in relation to intact stability especially for ships and vessels that relatively often operate beyond the operational conditions defined during the design. Therefore, operational safety measures can be an effective approach to reach acceptable levels of safety, especially for operations with large uncertainties.
Link to more info on the original article:
Liwång, H., and Rosén, A., 2018,"A framework for investigating the potential for operational measures inrelation to intact stability", 13th International Conference on theStability of Ships and Ocean Vehicles (STAB2018), Kobe, pp. 488-499.
Friday, 25 May 2018
I sometimes encounter people that try to solve a problem by knowing everything. For the systems a work with, and teach about, that is seldom an effective, or even possible way ahead. Today’s systems are often both complex and multidisciplinary and there is seldom an obvious path to take.
By instead understanding the system of interest you are able to make simplifications and assumptions to learn more about the system and the possible solutions. You will then get closer and closer to a solution.
|Some of the ropes that I figured out where to use. Photo: Hans Liwång © 2018|
I also tried this approach the other week when preparing my sail boat’s rig and sails for the season. I had a lot of ropes and blocks of different colors, types and sizes. I did not remember where they should go, but I knew the functions the finished system should have. From that I solved the problem without needing to remember anything about that specific rig.
Friday, 13 April 2018
Safety on board naval vessels – does the specific operational conditions make safety efforts and safety lessons based civilian maritime work irrelevant?
Today, the safety work on military vessels is influenced by civilian approaches, regulations and codes. This influence introduces important civilian lessons into naval vessel design, but can also potentially be in conflict with military task solving. One regulation, which is largely influenced by IMO codes, is the Swedish Military Ship Code formulated by the Military Safety Inspectorate. Risk management could present an approach for investigating if the civilian influence on the code leads to decisions and solutions that hinder military task solving. IMO’s Formal Safety Assessment (FSA) is a risk-based approach for such an investigation.
The effect of using IMO and classification society-based codes for the design of naval vessels has been found to assist in the engineering process and to guarantee a basic level of safety. However, the civilian naval engineering practices are not sufficient for guaranteeing survivability and thus safety in military cases. However, there could be a potential conflict between the rules that prescribe aspects of vessel use, and military task solving.
In 2010, the Swedish Navy introduced a new rule re-defining the sea area of safe operation for respective classes of vessels. The new rule is based on an EU directive developed for European passenger vessels. The Swedish Military Ship Code is not intended to limit military (wartime) operations. However, a Swedish naval vessel does (as most naval vessels do) always operate under a basic readiness level and therefore under military conditions. The potential conflict between rules that limit vessel use (rules for areas such as operations) and military task solving have not, so far, been investigated.
The objective of the published article was to describe the investigation performed and to focus on the meta lessons identified by applying the FSA structure to a military maritime safety case. The investigation analysed the safety level in the Swedish navy as a result of the regulation on sea areas of safe operation. The objective of the described investigation was to investigate the safety impact of the new sea areas given the Swedish Navy’s concept of operation, staffing structure, and competence. An additional objective was to determine if the rule is cost effective, and whether, if needed, sufficiently low risk can be achieved by an alternative rule, which has less impact on the Navy’s operations.
The investigation identified that it in the period studied there have been safety issues leading to risks higher than negligible. For the studied severe accidents, the identified risk levels are a result of decisions made on-board when solving military peacetime tasks. However, the quantitative analysis of the nine severe accidents shows that not only the human element affect the probability of an incident. Thanks to the military education, training, organization and personal safety equipment severe incidents that involve high speeds, cold water and vessels lost or severely damagedalso often result in relatively low levels of consequences. Such incidents would typically lead to multiple fatalities for a civilian vessel.
The less severe incidents leading to injuries were most often a result of maintenance work performed on-board independent of the vessel operation. Therefore, in the material, there is a low number (<1) of accidents per year related to the vessel operation with potentially severe consequences and a higher number (>5) of accidents per year related to work on-board leading to injuries.
An investigation in accordance with the FSA, as performed in the described investigation, in qualitative terms analyses both the effectiveness and the effects of the rule. Therefore, an analysis
can show if a regulation affects safety in the manner intended and if there are other means by which the regulation affects the operations. However, in order to reach high validity, the FSA approach needed to be supported by more explicit support on uncertainty treatment and propagation and by a peer review with strong contextual knowledge. The quantitative risk estimated was not, and should not, be in focus.
The investigation particularly highlights the need for an approach for analysing proposed safety changes both in terms of effectiveness and in terms of suitability. In 2008, after the accident in which Combat boat #848 was lost, the Swedish Accident Investigation Authority recommended 11 changes. One of those changes was to implement new sea areas of safe operation according to the civilian regulation; in addition, there were several regarding strengthening the crews’ risk understanding. In this investigation, the recommendation to implement new sea area limitations is shown to be problematic in several ways:
- the proposed changes would not have affected the accident with Combat boat #848
- the proposed rule to implement was neither understood nor analysed by the Swedish Accident Investigation Authority, and
- the proposed changes most likely affect safety culture negatively, as the changes prescriptive nature of safe and unsafe sea areas contradicts the general need to develop the crews’ risk understanding.
From this example, it can be identified that the effectiveness of the proposed changes must be analysed by the Accident Investigation Authority or by the Armed Forces. The result of an accident investigation is a set of recommendations; however, these recommendations must be analysed before they lead to new rules, particularly if the recommendations affect operation types that the Accident Investigation Authority have limited insight into. It must be ensured that new rules have the intended effect on safety; this responsibility must be taken by the organization deciding the new rules.
This investigation has shown that the recommendations to change the sea area rule led to a rule that has very limited positive effects, possible far-reaching negative effects and substantial operational costs.
The safety level for a vessel is a complicated relationship between several factors including the vessel type, the quality of the vessel’s maintenance and the vessel operation (seamanship). This finding is also identified in this investigation. It is stated in earlier studies using the FSA approach that “human error problems” can and must be included. However, this study shows that human element strengths also can and must be included, as they had an important impact on the link from incident to consequence and are an important part of the seamanship. The study identified that the high level of safety training of the persons on-board was important to making sure that severe incidents often lead to relatively limited or minor injuries.
An approach in accordance with the FSA structure is suitable even for areas outside the IMO’s typical scope. The FSA structure does not limit the approach to operational conditions as defined by civilian ships. However, the analysis needs to incorporate operational knowledge suitable for the area under study.
The military vessels’ concept of operations differs from civilian ships in such way that civilian safety rules can become irrelevant.
The case examined also raises many questions such as about how to articulate the actual difference between civilian and military contexts, especially in peace time; about how risk to individuals should and could be compared to national security risks as a result of operational limitations put on armed forces; and about how different types of hazards combine to create risk. These types of questions that are dependent on the connections between the organizations and technology under study and the Swedish society in general are largely here left unanswered. However, answering such questions without concrete examples easily becomes abstract and will therefore not affect decision makers. The hope here is that the case studied and described can be used as one example that together with other suitable and complementing examples can assist in making future conclusions that assist decision makers and increase the understanding of applicability and validity of risk management in state safety and security issues. However, it is unlikely that the perspective on risk presented by the FSA alone can answer such important and complex questions. Compared to traditional risk analysis of technical systems the FSA covers more aspects of the socio-technical system studied. However, the analysis power provided is not, and not intended to be, an approach that can be said to fully represent risk and safety in socio-technological systems.
Also more specifically in relation to this case further work, both in regard to how central parameters should be measured or calculated and more overarching questions, is needed. In relation to the definition of central parameters, it is important that such definitions (such as how to calculate the number of ship years) are clear and communicated. Two overarching questions that need further investigation are how risk limits in relation to military tasks should be defined and how to define and assess operational costs in general and quantitatively.
The extra risk introduced by antagonistic threats is not assessed, and the crews have not been tested in relation to such conditions. Therefore, the negative effects of the rule (as a result of the civilian and commercial background), which reduce the crews’ need for continuous risk assessment on-board, could be even more harmful to war-like military operations than what is shown in the material studied.
Tuesday, 10 April 2018
I was recently asked to write a text about maritime administrations. I choose to focus on maritime security and what a Swedish maritime administration in regards to maritime security is or should be: Below are some of the points I tried to make:
To enable economic stability and commerce, it is necessary to protect the free flow of goods shipped by sea (Council of the European Union, 2014, MNE 7, 2012, Secretary of Defense, 2012, Swedish Maritime Administration, 2014, Till, 2009). The shipping system is composed of many autonomous, but interconnected, actors (Swedish Maritime Administration, 2012) ranging from small local ship owners to large international ship operators.
Maritime security is addressed at many levels, from international bodies such as the United Nations (UN) and the International Maritime Organization (IMO) to single ship operators, but also by both military and civilian organizations. These levels and organizations are interconnected and a security decision made by one will affect the others (Liwång et al., 2015, Swedish Maritime Administration, 2012).
In this text a Maritime Administration is understood as the national body/bodies that issue government policy for ships and boating in relation to maritime safety and security (other important tasks in relation to areas such as environmental control, certificates of competency and representing the country on IMO and so on are not under study here).
For civilian ships and ports, today’s threats are managed through international maritime safety efforts regulated in the International Ship and Port Facility Security (ISPS) code (IMO, 2002) which puts substantial responsibility in relation to ship security, on the operators. The code was developed in the aftermath of the September 11, 2001, terrorist attacks in the United States. According to ship operators and security experts, the code does not guarantee secure shipping (Liwång et al., 2013, McNaught, 2005) and can only be considered as a first step (Mitropoulos, 2004). Also, the risk based security decisions taken by ship operators will only, at best, consider the specific operator’s commercial rationality, not the strategic interests of a region. Several Swedish studies has indicated a need for strengthening national transport coordination in response to crises, both as a result of a disruption of the transport system itself (Mötesplats Transporter, 2009, Samverkansområdet Transporter, 2007, Swedish Civil Contingencies Agency, 2014, Swedish Maritime Administration, 2012), but also to avoid that a crisis in other areas and sectors affect the transport system (Samverkansområdet Transporter, 2006, Swedish Civil Contingencies Agency, 2014, Swedish Maritime Administration, 2013, 2014). However, specific Swedish efforts for maritime security are hard to identify.
In Sweden the public debate in regard to maritime security has mostly been limited to piracy off Somalia and legal aspects of armed guards on ships, two issues with little relevance for maritime security in European waters. However, outside the public eye there have also been specific studies, analyses and exercises initiated by Swedish government agencies such as the Swedish Maritime Administration (Swedish Maritime Administration, 2006), the Swedish Radiation Safety Authority (the exercise Pilot 2015) and the Swedish Armed Forces (a staff exercise regarding maritime security 2016) and academic studies, see for example University of Helsinki (2009). These works typically deal with a single terrorist attack against a ship under Swedish flag and includes several organizations and government agencies, but not a complete maritime security system perspective based on the nation’s strategic transport needs.
All states must consider the capabilities needed to ensure maritime security in relation to relevant security threats. According to a workshop with representatives from transport security stakeholders in Sweden there is a need for better knowing and understanding the risks in the transport system and for identifying an acceptable minimum level of the society’s protection (Mötesplats Transporter, 2009). Subsequently, a need for strengthening also the understanding of the maritime security system has been identified. Also, the existing research in maritime security is limited. Previous research, such as Bichou (2008), Liwång and Ringsberg (2013), Liwång et al. (2013) and Psarros et al. (2011), show that empiric data on the shipping system as well as on specific incidents is needed to be able to discuss measures and risk control options. It is also clear from the previous research on society protection in general, such as Cedergren and Tehler (2014), and on maritime security specifically, such as Schneider (2012), that measures are needed on several different levels of the system (Cordner, 2014).
To reduce the above-identified challenges there is a need for systems approach that examine different aspects and levels of the maritime security system and how the system delivers utility to a nation or region. Therefore, it must be made sure that maritime security capability (from a system perspective) is correctly designed and distributed between different system levels to ensure sufficient security. A nations maritime administration has a central role to play. However, also other stake holders take decisions that greatly affect maritime security. Such stake holders include autonomous ship operators as well as law enforcement agencies that both lack a system level knowledge. This aspect presents specific challenges for the region, nation, organization responsible for ensuring sufficient maritime security. From this it also follows that a system perspective on maritime security here means that maritime security is viewed in relation to the shipping system and its roles in a region. It also means that the focus is on a nation’s (or set of nations’) capabilities and efforts needed.
A need for a risk governance approach
Risk is not constant and especially security risks are subject to considerable degrees of uncertainty. The rarer the event, if predictable at all, the less reliable the historical data and the estimates based on them are (Aven & Krohn, 2014, IACS, 2012). Regulations, guidelines and methods in the field of maritime safety have a history and culture of systematic research, development and implementation (Kuo, 2007). In contrast, international security is highly politicised and therefore not as transparent (Wengelin, 2012). Therefore, the tradition of maritime security is not well established (McNaught, 2005), this affects the work performed at maritime administrations in relation to maritime security. Applying risk-based approaches to security areas requires special considerations. Therefore, there is a need for both further research and applied development of methods and tools. This development must be able to manage the new, more complex demands within maritime security (Department of Defense, 2007, McNaught, 2005).
It has been identified that a whole systems approach is needed for transport studies in general (Swedish Civil Contingencies Agency, 2014) and for maritime security specifically (Bateman, 2010, Schneider, 2012, Schofield et al., 2008) and therefore a framework for understanding the maritime security risk governance is here adopted. Here a risk governance process is understood as a set of activities and actions taken by various stakeholders to manage risk in a context characterized by uncertainty, complexity and ambiguity. To be able analyse conditions where no single stakeholder can dictate the conditions the concept of risk governance has been introduced (Bateman, 2010, Cedergren & Tehler, 2014, Schneider, 2012). According to the research by Cedergren and Tehler (2014) there is, in risk governance, a need for taking into account the ways in which risk-related decision-making is performed in settings where many stakeholders are involved, and where these different stakeholders may hold diverse meanings of the concept of risk (Rasmussen, 1985). The approach therefore here aims to answers questions about the purpose, function, and form of a maritime security risk governance (Cedergren & Tehler, 2014).
Identified Maritime Administration challenges
Performance of organizations, such as ship operators as well as maritime administration agencies, should be assessed by their contribution to the risk governance system. Therefore, an investigation was performed to identify such contributions from the Swedish Maritime Administration and the Swedish Transport Agency since 2006.
In 2006 the Swedish Maritime Administration (2006) based on the yearly risk and vulnerability analysis stated that the sector had, compared to other types of risks, the “best ability … to handle the event terrorism”. However, this claim was done without any extensive explanation and since then no risk and vulnerability analysis has been performed in relation to maritime security. The latest Swedish maritime safety report Säkerhetsöversikt 2016 has no mentions about maritime security, ship protection measures, crime at sea, or the effects of criminal activities on shipping (Swedish Transport Agency, 2017). Also, the Swedish Transport Agency has no specific maritime security information for Swedish conditions or for the sea areas of specific interest such as the Baltic Sea. Therefore, there is very little evidence of that, and how, the Swedish government agencies implement and enforce maritime security (other than administrative tasks in relation to the ISPS code).
The lack of clear maritime administration activities contributing to the maritime security risk governance system coupled with exercises examining single events (rather than system events) lead to a system understanding. This makes it challenging to other system stake holders, such as the Police, the Coast Guard and the Navy, to understand and adapt their activities in an effective manner.
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