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Advanced level-2 structural reliability theory is applied to the reliability analysis of deck and bottom (amidships cargo/ballast tanks) stiffened panels of two alternative large oil tanker designs in order to assess the safety of the current Lloyds Register Rules used in their construction. Basic theory inlcuding the treatment of time- varying is explained and details of the uncertain quantities studied (including still-water bending moment vertical wave bending moment lateral pressure steel mill rolling control and corrosion) included. The preliminary nature of the work is emphasised.

Norwegian insurance companies adopted common building rules for ships and established Det Norske Veritas (DNV) as a national classification society. The Classification Society's mode of operation and relations with other players in the marine industry are discussed. Special consideration is given to the commitment of DNV to safety at sea. Reference is made to data collection and research work carried out. This work shows that the overall safety of seamen is threatened more by the general social conditions for seafarers than by the technical condition of the ship.

Insurance implications of manning and training are considered. The cover for owner's liability to crew numbers rather than consequential liability resulting from crew errors and omissions is discussed. Reference is made to the P&I Clubs' own statutes and rules which establish cover. The main provisions are highlighted which show how manning and crewing impact a shipowners' P&I cover. Statistics for crew claims are given. Contractual compensation pre-employment medical examinations (PEMEs) re-employment and training are discussed from an insurer's point of view.

The European Communities' policies for dealing with marine pollution are looked at. The issues of joint action and enforcement are touched upon. Marine pollution is discussed. European Community action and initiatives are outlined. The role of the European Parliament is considered. It is concluded that since pollution by one party affects the environmental quality of another party joint action is needed to combat pollution effectively. The EC has a pre-eminent role in helping to formulate international rules but as a single body rather than as a collection of states.

A description is provided of how the provisions of classification are applied to naval ships and how Lloyd's Register's Rules and Regulations for the Classification of Naval Ships have been developed. The development of a flexible system which meets the needs of different navies to enable them to bring within the scope of classification specialised ship structures and engineering systems is presented. First a look is taken at the classification process followed by naval ship classification. Next military aspects are considered. After this commercial standards and international conventions are looked at.

An overview of the architectural arrangements of various power generation and distribution systems installed on ships is given. The criteria employed by Lloyd's Register of Shipping (LR) to address the risk of damage and fire are described. The impact of increasing the size of generator sets is discussed in relation to ship arrangements. Changing diesel engine prime movers to gas turbines is also considered in relation to ship design and electrical architecture.

Comparative discussion examines government (USA UK Norway) legislation and classification society (ABS DNV GL NKK RIN) rules concerning the stability of floating offshore platforms. The Lloyds Register computer system for assessment of stability of offshore units is described with the theoretical background to calculation of intact stability damage stability wind moment allowable vertical centre of gravity and hydrostatic data. Application of stability criteria to semi-submersibles is considered.

The regulatory approach to shipping has traditionally been based on prescriptive rules with many technical requirements. New regulations were often driven by a reaction to accidents. The regulations were enforced by inspections and punitive action. The regime has often been criticised and there is now a move towards self-regulation to encourage a safety culture in the industry. These changes are discussed with particular reference to the International Safety Management Code.

In order to operate in the territorial waters of most countries an FPSO will be required to comply with classification rules national authority standards statutory regulations and relevant codes and standards. In the UK new verification regulations are replacing the existing certification scheme. An effective way to deal with classification is through integration in the project team. Design issues include FPSO structure turret mooring system and process facilities. To ensure that the installation remains in a satisfactory condition it is a requirement of classification that inspection and repairs are carried out periodically.

The introduction of DNV (Det Norske Veritas) high speed and light craft rules based on the new class concept is described. They include IMO HSC (high speed craft) code requirements. The requirements for domestic vessels were achieved through the introduction of a chapter on service conditions. The service conditions concept is presented; the technical standard for a specific service condition is based on a defined sea state condition. Classification parameters are identified.

The first part of this paper recognises the potential for high-speed sea transportation and presents DnVs philosophy for classifying such vessels. The second part presents a designer's guide to the methodology used in the development and application of the required design loads according to the new 1991 rules for classifying high-speed and light craft. DnVs procedures for strength analysis and design criteria are also presented.

Classification is a Quality Management and Control System in merchant shipbuilding and shipping. It forms a vital element in the protection of human life at sea the technical safety of the ships and the protection of the oceans against environmental pollution. This paper describes the basis for classifying naval vessels the development of the Rules for Classification and Construction of Naval Ships. In addition it shows the actual trends and benefits for the navies by the example of the ANZAC-class frigates of the Royal Australian Navy.

Recent legislation has introduced the requirement for all new tankers to have a double hull. DnV's response in terms of design fatigue corrosion trading and maintenance of tankers is considered and experience to date is highlighted.

The traditional ways of developing standards for marine engines based on incidents and failures are becoming outdated. The development of international standards for marine diesel engines from the relatively low-powered units first used in ships to the current and future complex high power engine installations is reviewed. The background to the current classification rules for diesel engines that stem in part from SOLAS and IACS requirements are identified.

In this paper possible approaches are examined suitable for investigating the structural response under seismic loads. Most of the Classification Rules individuate two levels of design earthquake - Ground Motion Evaluation (GME) and Rare Intensity Evaluation (RIE) corresponding the first to the Serviceability Limit State and the second to the Ultimate limit state. When the last one is examined a method is adopted capable of taking into account non linear effects; a transient dynamic analysis then needs to be performed.

Classification Societies require that electrical installations be protected against accidental overcurrents including short circuits and other electrical faults. An accurate assessment of short circuit currents is necessary to allow selection of protective devices such as circuit breakers and fuses. Protection relays based on microprocessors allow a range of functions. Power management systems are discussed: the problems of waveform distortion by harmonic currents generated by static power converters may be overcome by the use of harmonic filters. Classification Society rules have requirements limiting voltage and frequency transients.

Networks form the information backbone of modern military platforms and are a key technology for the network-centric aspirations of the joint services. However many existing networks are neither open nor future-proof and through incompatibility constrain those aspirations. This paper examines a layered services-based approach to the generation of a true open Electronic Architecture. It describes a toolset that automates aspects of the design and enforces the open rules required to generate a successful Electronic Architecture. The aim of the paper is to show how flexibility can be designed into electronic architecture ensuring simplified future upgrade paths by isolating the war fighter from the impact of future hardware and communications standards.

Two separate areas are considered: maritime pollution - emissions and releases to air and sea; and the experiences of TRESHIP after working with Thematic Networks over four years. It is concluded that while shipping is the most environmentally friendly transport form available there is still interesting potential for improvement. For shipping companies it is a fine balance: too little action and the company may not be complying with rules and regulations; too much action and the company may loose competitiveness. The main change required is changing from a compliance culture complying with prescriptive and reactive regulations to a proactive and self-motivated culture implementing improvements.

FSA (formal safety assessment) is a structured and systematic methodology aimed at enhancing maritime safety by using risk and cost- benefit assessments in developing rules. How DNV (Det Norske Veritas) uses the FSA methodology to enhance the quality of their rule making is described. The focus is on an overall safety philosophy as well as on practical examples of how they link the safety philosophy to prescriptive regulations.

Det Norske Veritas' methods for predicting allowable stresses and external loading with corresponding quasi-static and dynamic response in marine propeller blades are summarised. Cumulative damage aspects are introduced together with a study of the significance of defects. Fracture mechanics calculations and experiments are combined to assess the blade life when cracks are presented.