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Offshore LQ (living quarters) are typically designated to be or to contain the TR (temporary refuge) including the installation's CCR (central control room) and as such are required to withstand both direct and indirect effects of explosion. LQs are generally located as far as practicable from areas where significant explosion hazards exist. However there is a possibility of LQs being exposed to some residual effects of blast overpressure from an event originating elsewhere on the installation. Guidance on the calculation method used for distribution of external blast overpressure on the LQs is provided. Also given is advice on the application of non-linear finite element analysis methods. However the emphasis is on the aspects of a manual method which can be used with or without the design software.

Upon the request of PEMEX a vibration assessment was conducted on an offshore platform located in the Bay of Campeche. The study consisted in two parts - the first being considered in another paper and the second one involving the response analysis under uncertain conditions of wave height. The uncertainty on the wave loading was considered through the annual probabilities that given wave heights are exceeded. The probability that the platform response exceeds an allowable threshold conditional to given wave heights was assessed. Those conditional probabilities were weighted later on over the annual probabilities that those wave heights are exceeded. The responses are displacements accelerations and forces. The lateral strength of the platform was calculated by assuming a failure mechanism composed by the simultaneous formation of plastic hinges at the ends of the platform legs.

Shell UK Exploration and Production operating on behalf of Shell and Esso is developing the Teal Teal South and Guillemot A oil fields in the Central North Sea with a floating production storage and offloading system (FPSO) coupled to subsea wells. The FPSO comprises a storage barge fitted with a turret mooring system at the bow and living quarters in the stern. Production and utility systems are arranged on raised platforms above the main barge deck and an offloading system mounted on the extreme stern. The design development of the FPSO (Anasuria) is presented including details of the safety case and the execution plan for first oil in the summer of 1996. Information is provided for the barge living quarters safety features production facilities vessel motion FPSO control utilities power generation and the turret mooring system. The interfaces between SBM who designed the turret in Morocco Stork Protech who designed the topsides in Holland MHI who designed the barge in Japan

This article discusses the installation of the Piper B jacket reputed to be the safest platform in the North Sea. It incorporates many of the Cullen Report recommendations with steel blast walls around the living quarters free-fall lifeboats over-pressurisation to prevent smoke entering the living module and a host of fabrication safety features. Economic factors and ownership are also considered.

The review presented covers the effect of ship size and effect of increased cargo specialization and safety eg. fire fighting. Amenitites are discussed including living quarters ventilation system domestic water supply and sewage disposal. Automation and level. Deep sea moorings actuaillary services eg. waste heat boiler and self-cleaning separator etc. and the reliability of services are considered and future prospects eg. nuclear propulsion increasing size and the effectiveness of the hovercarft and hydrofoil are examined.

A number of recommendations from the Cullen Report point to the accommodation module being classified as a `safehaven' or `temporary safe refuge' in the event of a major incident. The existing prescriptive regulatory regime is to be replaced with objective requirements based on a formal safety assessment. The paper reviews living quarters as TSR's design and construction and existing facilities.

Bouygues Offshore in association with Sedco-Forex and IFP have designed the Multi-Function Barge (MFB) which combines the oil and gas treatment utilities and living quarters that Bouygues developed for the Nkossa project with crude oil storage and offloading functions. The barge layout mooring in the mild Gulf of Guinea environment operation and satellite tie-ins are discussed.

A brief review of the Floating Production & Storage Offshore Unit (FPSO) market development is given. The Glas Dowr a new building crude carrier bought by Bluewater from a Japanese shipyard for conversion to a FPSO to be stationed between the Durward and Dauntless Fields in the North Sea is described. The conversion of this ship started in May 1996 at the Harland and Wolff facility in Belfast and the final outfitting work is to take place at an offshore construction yard on the North East coast. The conversion scope is discussed covering the hull topsides upgrading of living quarters and equipment/system modifications.

The main cause of underway vibration on modern ships comes from variable loads due to the propulsor. The effect of these loads can stimulate fatigue stress in the hull and lead to impermissible vibration levels in living quarters and interfere with the operation of various shipboard devices. The model for computing variable forces arising from ducted propellers in non-uniform flow is presented. The computational amplitudes of these forces is compared to experimental data.

Non-linear dynamic analysis for offshore structures has been a major challenge in marine structural and earthquake engineering. Jacket-type offshore structures consist of a tubular frame connected to the seabed by pile foundations which are driven through the soil. The deck modules consist of a series of elements which house equipment helipad or living quarters modules. A model considering the overall behaviour of the structure is used and IDA (incremental dynamic analysis) is done to assess the non-linear behaviour of jacket-type offshore platforms subjected to earthquake. The IDA analysis model is presented. Numerical modelling is described and simulation results are presented.

FPSOs have become the solution of preference to develop deepwater blocks offshore Angola. Two studies are presented which were carried out by ADC (Angola Deepwater Consortium) for the leading operators in the region. The aim was to find ways of reducing the cost of FPSO developments and to determine a generic solution for the hull systems and living quarters appropriate for a new-built Angolan FPSO. Key considerations for cost reduction are described together with the characteristics of the FPSO which were selected by ADC to suit the service demands offshore Angola. The ADC design is aimed to serve as a reference basis for future FPSOs for Angolan developments.

BP's Harding development employs an innovative concept for North Sea oil production. A large permanently installed jack-up platform incorporating production drilling and living quarters is positioned on top of a concrete gravity storage base tank which holds Harding's acidic heavy crude before export to shuttle tankers. The use of horizontal drilling techniques in the early 1990s coupled with adoption of the above concept transformed a very marginal prospect into a viable development which currently has one of the lowest development costs per barrel in the North Sea. The viability of the development has been achieved using an entirely new approach to project management with a small integrated management team. The relationships created with design contractors suppliers and fabricators are shown to represent the embodiment of the principles of the CRINE (cost reduction in the new era) initiative and have secured for all parties benefits which can be used as benchmarks for future projects in a low oil price environment. Contractual arrangements are discussed and a new approach to operations and maintenance support contractors is highlighted. The concept has potential for reducing abandonment costs due to the relative ease of decommissioning and removal.