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The NATO Standardization Agency (NSA) is proposing a Naval Ship Code (NSC) that can be applied to surface naval vessels and other vessels operated by the armed forces or agencies of a state. The NSC is optional and based on, and benchmarked against, conventions and resolutions of the International Maritime Organisation.

The NSC cover areas such as ship controllability, engineering systems, fire safety, evacuation, communications and navigation. The code does not include measures specifically designed to address the effects of armed attack.

The covered areas in NSC are however also very important when the effects from armed attack is to be minimised. This work investigates how the NSC will effect, and interact with, measures to ensure survivability under attack. Survivability is here seen as a function of the ships susceptibility, vulnerabilityand recoverability. Based on two case studies this paper exemplifies the effect of the NSC on the vessels total safety. The case studies presented are ballistic protection on smaller naval vessels and bridge configuration to minimize effects of attacks.

Conflicts of today are characterized by both traditional and irregular tactics and by non-state actors making innovative use of modern technologies. These conditions set new demands on naval ships. The aim of this investigation is to describe how, based on probabilistic risk assessment, the concept of operation for a naval ship can be turned into safety scenarios to be used in the evaluation of risk. In this investigation, civilian state-of-the-art methods for probabilistic risk assessment are merged with the specific demands of naval ships. Relevant aspects of safety culture, codes, regulations and rules are analysed with respect to requirements on safety scenarios, and military operational research with respect to modelling military systems. The results show that the scenarios must have calculable probability and must be adapted to the vessel in question. Results from simulations show that modelling operational tasks is one way to support experts in the definition of safety scenarios.

This study reviews ship security assessment. The objectives are to explore the possibilities for quantifying and performing a more thorough ship security risk analysis than that described in the International Ship and Port Facility Security code and to evaluate to what extent this more detailed analysis increases ship security and facilitate the effective selection of risk control options.

The study focuses on Somali-based maritime piracy, using piracy on the Indian Ocean as a case study. Data are collected using questionnaires and interviews with civilian and military security experts who possess firsthand experience of piracy off the coast of Somalia. The data are collected specifically for this study and describe and quantify the threat’s capability, intent and likelihood of exploiting a ship’s vulnerability. Based on the collected description of the threat, the study analyzes and describes: probability of detection by pirates, probability of successful approach, and probability of successful boarding.

The performed work shows good agreement between calculated probabilities and frequencies in the cited incident reports. Also, the developed scenarios describe the most important influences on the analyzed areas. The research therefore shows that the proposed risk-based approach, which uses structurally collected and documented information on the threat, can increase ship security by assisting in selecting risk control options. The approach also allows for a better understanding of the causal relationship between threat and risk than that provided in today’s security analysis by ship owners, for example. This understanding is crucial to choosing effective and robust risk control options.

Military ocean patrol vessels (OPVs) are today an increasingly common type of naval ship. To facilitate the wide range of tasks with small crews, OPVs represent several ship design compromises between, for example, survivability, redundancy and technical endurance, and some of these compromises are new to military ships.The aim of this study is to examine how the design risk control options in relation to survivability, redundancy and technical endurance can be linked to the operational risk in a patrol and surveillance scenario. The ship operation for a generic OPV, including the actions of the threat, is modelled with a Bayesian network describing the scenario and the dependency among different influences.The scenario is described with expert data collected from subject matter experts. The approach includes an analysis of uncertainty using Monte Carlo analysis and numerical derivative analysis.The results show that it is possible to link the performance of specific ship design features to the operational risk. Being able to propagate the epistemic uncertainties through the model is important to understand how the uncertainty in the input affects the output and the output uncertainty for the studied case is small relative to the input uncertainty. The study shows that linking different ship design features for aspects such as survivability, redundancy and technical endurance to the operational risk gives important information for the ship design decision-making process.

In military operations, balancing risk is central, and a desire to entirely avoid risk may affect the potential for achieving military goals. Therefore, risk is an important aspect for understanding the operational conditions. This study discusses the assessment of operational risk to support ship design decisions.

Fire is a common consequence of weapon hits and is currently estimated to cause of 80 percent of naval ship loss. The purpose of this study is to describe and investigate the conditions for a risk-based approach to ship fire survivability, that can link probabilistic survivability theory and survivability measure selection. The aim is to suggest key aspects for a risk-based methodology.

To aid in the analysis, this study proposes cause and effect models for the fire risk analysis and describes the fire risk contribution from different types of ignition. The analysis shows that the reliability and validity of identifying potential fires depends on a qualitative and outward-focused analysis of the ships’ intended operation, and the reliability and validity of the analysis on fire consequences depends on the specific data and descriptions used. For example, the magnitude of the fire risk can drastically change due to the operational choices (or unclear operational conditions).

This study concludes that the analysis requires understanding of the operational conditions. Subsequently, civilian risk-based approaches to fire risk are too limited because the approaches do not include aspects of the ship design and intended operation. Further, normal military vulnerability tools lack this ability. However, based on a stringent fire ignition analysis, including a definition of the intended operation, the ship design concept and the threats, civilian methods and tools can be used to assess the consequences.