A New Integrated Deck Concept

Milazzo Refinery (RaM) has developed a new safety system to minimize the risks related to "hot works" (mainly explosion risks) during normal unit operations. The good practice was for the first time utilized during Fluid Catalytic Cracking pre-turnaround and turnaround phase from Milazzo Refinery. At that time, RaM implemented, for the first time, the integration between the existing network system of fixed hydrocarbon detectors with the welding machines through the Distributor Control System (DCS). This integration allowed to immediately switch off the power supply to the welding machines in case of detection of explosive atmosphere. Moreover, in order to cover as many welding points as possible, several mobile detectors were installed and integrated in the gas detectors system. The whole process is represented in the scheme in Figure 1. The main benefits of such integrated safety system were as by following: Mitigation of the risks related to hot work execution during normal operations with consequent safety improvement. This also allows, during turnaround, to maximize the preturnaround activities so that its duration can be profitably reduced;Increase the quality of the measure which is continuously detected and monitored by electronic devices (operator originally used to detect if the atmosphere was hydrocarbon free only before "hot work" execution. During the pre-turnaround phase, with FCC Plant in normal operation, more than 200 tons of piping steel and more than 400 tons of steel structures were installed and welded without any incident or injury to direct personnel or contractors. The successfully implementation of the integrated gas detectors system has become a new standard within the refinery to increase safety in the execution of "hot works " during normal unit operations, strongly mitigating the risks related to explosive atmosphere. Moreover, this system also allowed to speed up the execution of the "hot work" hence it became a RaM standard for similar process.

This book provides comprehensive information essential for both the design of new steel structures and the analysis of existing ones. It covers the fundamental principles of design, procedures, historical context, specifications, and the Turkish standard TS 498 for design loads. It also addresses probability and factor of safety, the application of steel in structures, the mechanical properties of structural steels, and an introductory comments on TS 498. The book covers fundamental concepts including the behavior of tension and compression members, methods for their analysis, and details regarding compound struts. Compound struts with uniform cross-sections, designs for them in groups I-II-III, struts with varying moment of inertia, and cross-ties are addressed. Essential information on Mohr’s Circle equations and the product moment of inertia are reminded. Subsequent chapters delve into beams, lateral buckling, and beam-columns, making distinctions between beams subjected exclusively to bending and those subjected to both axial loading and bending. Additionally, analysis of fasteners, such as rivets and bolts, include design factors like length, diameter, fastener spacing, weight, modes of failure, types of fastened connections, design assumptions and allowable stresses, and other design considerations are included. Similarly, different types of bolts, advantages, installation methods of high-strength bolts, allowable stresses, and design considerations are discussed. The design of fastened connections, including direct shear, pure moment connections, and eccentric load connections for fasteners in shear, along with the AISC recommendations and the method of instantaneous center of rotation are explained. Combined shear and torsion as a more complex scenario are also addressed. Design rules for TS 648 and allowable stresses for steel structures are presented in tabular form. Further chapters cover welding, discussing its advantages and disadvantages, types, classifications, symbols, quality, defects, and key issues related to inspection and control. Specific types of welds, such as butt and fillet welds, are examined, along with stresses in welded connections, theoretical considerations, effective areas of welds, and additional considerations. Finally, the book covers torsion, including plate girders, trusses, splice and connection design principles, and allowable stresses. These topics are explored in depth through illustrative examples, and the book concludes with a presentation of a previous three-course examination. A brief introduction is included in this book, but detailed examples are decided to be included in future Steel Structures II book.

With the increasing scale and complexity of steel structure engineering, traditional inspection and pre-assembly techniques face bottlenecks such as low efficiency, high costs, and insufficient precision. This paper addresses issues in large-span complex steel structure projects, including low full-scale inspection coverage of components, significant registration errors in irregular joints, and resource wastage in physical pre-assembly. It proposes a comprehensive digital solution featuring “multi-scale point cloud fusion, intelligent feature extraction, and virtual error closed-loop.” By integrating the Leica P40 terrestrial scanner and HandySCAN 3D handheld scanner, full-coverage data acquisition for both global deformation and local details is achieved. Combining an improved ICP algorithm with Monte Carlo simulation, a dual-scale registration strategy and automated error analysis module are developed to resolve compatibility issues between global and local features of large-span components. A virtual pre-assembly digital twin is established, integrating feature matching, error simulation, and assembly sequence optimization, replacing 80% of physical pre-assembly. Engineering applications demonstrate that this technology increases inspection coverage from 20% to 100%, achieves a 98% recognition rate for detailed features, reduces pre-assembly costs by 70%, shortens single-truss pre-assembly cycles from 7 days to 8 hours, and cumulatively saves 1,414.4 tons of steel while reducing carbon emissions by 4,200 tons. The research outcomes provide theoretical support and practical examples for efficient construction of complex steel structures, significantly advancing the coordinated development of intelligent construction and green building practices.

As oil and gas fields mature and production declines, strategic decommissioning planning becomes crucial. This project explores innovative alternatives for transforming decommissioned wellhead platforms into new opportunities by reusing topsides for future installations in the Gulf of Thailand. By applying the fit-for-purpose concept, lowering CAPEX, and reducing environmental impact, this approach supports cost-effectiveness for future field development and aligns with global sustainability objectives, maximizing resource efficiency and paving the way for sustainable practices. The project followed PTTEP's structured reuse methodology, starting with candidate platform selection with the well depletion plan, topside facility integrity assessments, engineering evaluations for required modifications, and cost-benefit analysis comparing reused topside with new construction and traditional decommissioning. Key evaluation metrics focused on CAPEX, OPEX, decommissioning costs, and environmental impact. Additionally, design matching between the donor and receiving platforms was prioritized to optimize the modification costs. A comprehensive maintenance plan was developed to address equipment deterioration from idle periods, with proactive inspections and reconditioning to ensure long-term operational reliability and reduce the risk of costly replacements. The assessments of the candidate platforms confirmed that the topsides were structurally sound and fit for reuse, with no critical issues that would affect their integrity or performance in the new environment. The cost savings in CAPEX, including decommissioning costs, achieved through reuse ranged from 17% to over 40%, with an average reduction of approximately 36% compared to new builds. Environmentally, the reuse strategy provided significant benefits, including the conservation of materials and a GHG emission reduction. For each platform, approximately 670 tons of steel were saved, resulting in a reduction of more than 1,200 tons of CO2 emissions. Initial projects experienced higher costs due to non-standardized designs and ambiguous repair scopes. However, by incorporating lessons learned into subsequent initiatives, including optimized design matching, standardized engineering practices, and streamlined contracting processes, both modification costs and project timelines were significantly reduced. These refinements led to enhanced cost efficiency and expedited project delivery. In conclusion, the findings confirm that topside reuse is a technically sound, economically advantageous, and environmentally responsible decommissioning strategy, offering a sustainable solution that aligns with long-term field development plans with cost optimization. The topside reuse approach not only reduces waste and emissions but also enables faster and more affordable development of marginal fields. Additionally, the topside reuse practices can also be applied to other brownfield development projects of PTTEP and/or Join Venture in the future.

Scenarios and new technologies for a North-European CO2 transport infrastructure in 2050

The Murchison structure is barge-launched steel drilling and production platform which is to be floated out in Spring 1979 and installed in the Northern North Sea in 156m of water. In the past, offshore steel structures have been designed on the basis of an extreme static design load. Subsequently, the completed design has been checked for dynamic amplification and fatigue life. As structures are designed for deeper waters, from 150m depth their natural periods become longer and dynamic excitation can have a profound effect on the stress levels achieved in all wave- conditions. In order to meet the design requirements for dynamic and fatigue analysis a new suite of computer programs called FATJACK has been developed which embodies several innovations in the analysis of steel structures. The whole system is centered on the Atkins Stress Analysis System (ASAS). It uses the subspace iteration technique to handle very large eigen-vector extractions which are necessary if the structure is to be modeled with sufficient accuracy to find the dynamic stress levels in the smaller diameter members. This is followed by a deterministic analysis using a steady-state response to relate the climatic conditions to the dynamic response and hence fatigue life duration. The application of this program to the Murchison structure is described in detail. For example, the extraction of 25 eigen-vectors from an uncondensed structural idealisation shows significant low frequencies in the conductor tube bracing which have previously been undetected and this could explain the relatively high failure rates of this type of structural component found in the platforms of the Southern North Sea. In addition, a transient analysis using a Newmark-ß integration scheme has been undertaken to establish the dynamic amplification factors by comparison with the base reactions and deck level deflections for corresponding static load cases. INTRODUCTION The escalating demand for hydrocarbon fuels has necessitated the exploration and development of offshore fields in ever increasing water depths. The enormous size of the steel structures required for these depths has lead to a new breed of problem and, in particular, the fatigue and dynamic response of such structures has become increasingly important. Experience in the North Sea has shown that some structures are more prone to fatigue damage from small, low period waves rather than overload failures due to the long period storm waves. In previous static analyses of offshore platforms the environmental conditions specified for extreme loading and fatigue life calculations have been related but different. In the case of the extreme '100 year' storm condition a theoretical design-life wave, with a specified height and period, is applied to the structure at a point in time usually chosen by reference to the maximum mud-line horizontal shear force or overturning moment. It is arbitrarily assumed that this criterion will define the worst load case for all members and joints. In addition the design-life current is applied to the structure simultaneously to give a combined maximum load condition.

Greenhouses should be designed to meet requirements of construction costs, durability against loads and the possibility of providing suitable environment to plant growth. To get guides to design an optimal greenhouse from the above-mentioned three viewpoints, one of the optimization techniques, which is called the steepest descent method, is applied in this study. The direct light transmission into the greenhouse in winter is regarded as one of the most important environmental factors.The steepest descent method gives the combination of the design variables which constitute the optimal (minimum or maximum) value in the objective function under some constraints. In this study the design variables were, for example, the shape of the house, the moment of inertia and crosssection features of each member and the ratch measure. The allowable stress or deflection of each member played a role of constraints in the course of the optimization. The objective function was the construction cost or the direct light transmission. In the steepest descent method, however, only one objective function is allowed. For this reason the following two steps were used. First the construction cost (Js) is chosen as the objective function and is minimized. Then the inequality (1) is added to the constraints and the light transmission is maximized, where k is the coefficient of construction cost allowance and larger than 1.0, and Jsopt is the minimum construction cost.Because in the steepest descent method all variables should be continuous and differentiable, some discontinuous variables, e.g. the number of purlins, were approximated with appropriate continuous functions. For the same reason any size and shape of steel member were assumed to exist. The crosssection features of the member are expressed with three independent variables on the basis of the empirical relations.The optimizations were carried out under the conditions of a snow load of 30cm and a wind speed of 50m/s. The span was fixed at 9m. The latitude and the coefficient of construction cost allowance in the optimization of the light transmission were 34°N and 1.10, respectively. The following points became clear by the optimizations.1) The steepest descent method can be applied to greenhouse design and the results show appreciable improvement both in the construction cost and in the light transmission in comparison with an example of commercial greenhouses.2) The results of the optimization of the construction cost (cost optimization, hereafter) and the light transmission of the N-S oriented greenhouse (N-S optimization, hereafter) show a symmetric shape, whereas the optimal E-W oriented greenhouse has a ridge nearer to the south wall, so that the south roof slope becomes steeper.3) Every optimization results in a ratch measuer of about 4m, which is wider than that of commercial greenhouses.4) The moment of inertia of the rafters and the posts ranges from 150 to 290cm4. In the cases of the cost and N-S optimizations, the rafters have a larger moment of inertia than the posts. In the E-W optimization, the north rafter has an appreciably larger moment of inertia than the three others.5) The cost optimization shows that members of the crosssection with larger depth and width are more suitable for the rafters and the posts, if the moment of inertia is the same. This holds true for the north members in the E-W optimization and for the posts in the N-S optimization. In the E-W oriented greenhouse, a member with shorter depth and larger section area and a member with shorter width are more suitable for the south rafter and for the south post, respectively.6) In this study the strength of the glass was not taken into consideration. This resulted in very wide purlin intervals, which seem to be unrealistic, but this still proves that larger purlins with wider intervals are more suitable

The stability of structures in deep waters offshore is of particular concern to the oil and gas industry and to registering authorities. Over the last four years, Harwell has developed nuclear instrumentation and tracer techniques to measure the density and movement of grout used in the installation of steel jackets to the sea bed. These methods have been applied to a number of steel jackets in the North and Celtic Seas where weather conditions can greatly affect the application of traditional methods of visual inspection. This paper describes the development of these activities from the laboratory to their application on the largest steel structures in the North Sea and gives details of some of the results obtained. Extensive laboratory tests have been carried out on the installed equipment to determine their response to prolonged immersion, variations in temperatures between installation and operation conditions, vibrations and shock loadings experienced during hammering of the piles. Nuclear grout density gauges have been used also for the control of grout mixers resulting in considerable improvement in the quality of grouts used for platform installations. The development of radioisotope gauges and tracer techniques has reduced the dependence of installation operations on the use of divers, thus making the operation inherently safer and reducing the effects of weather conditions on operational programmes. In addition, registering authorities are now able to have direct confirmation of the presence of grout in pile sleeves, information on seawater/grout interfaces, and in-situ measurements of grout densities during and after completion of the grouting activities. INTRODUCTION A continuing increase in the world demand for oil products and the regulation of supply from oil producing countries, have raised the price of crude oil dramatically over the last decade. This rise in price has provided further incentives for the exploration and exploitation of oil and gas reserves in offshore areas where previously extraction would have been uneconomic. As a result, development jackets and oil production platforms are being used in deeper and more hostile waters than hitherto. Structure size has increased and previously satisfactory installation procedures have become unacceptable as they conflict with the constructional design requirements and weather conditions. An important aspect of installation of steel structures has been their piling to the sea bed and the subsequent cement grouting of the piles to the strata and the pile sleeves. This activity is generally carried out by a grouting contractor with grout mixing and pumping equipment on an accompanying construction barge or on the structure itself. The quality of the pumped grout is checked at the mixer. Also various methods have been employed 1, 2 to check that the grout has been pumped and remains at its intended place. These have included visual inspection and sample retrieval by divers, the use of return lines to the surface and the measurement of conductivity.

In the past, allowable stress design (ASD) was used to design steel structures. The allowable stresses used were determined from previous practice, with limited understanding of the reliability and risk performance provided by the structure. Engineering methods based on Load and Resistance Factor Design (LRFD) provide more accurate lifetime models of structures by providing risk-based load factors. Besides improved safety, cost savings can be provided through improved performance and, in some cases, by delaying rehabilitation. This research project develops LRFD-based engineering procedures for the evaluation and design of hydraulic steel structures (HSS). Hydraulic loads are a key element to the LRFD analysis. This report identifies the primary hydraulic loads and describes procedures that can be used to determine these hydraulic loads. Existing design guidance for HSS is described and presented in the individual chapters. The appendixes to the report provide examples of the procedures used to compute the hydrostatic, wave, and hydrodynamic loads. A new approach for determining wind-induced wave loads was developed. Design guidance for computing the hydrodynamic load was limited for many of the HSS. Additional research is recommended to improve capabilities for computing hydraulic loads. Details on these recommendations can be found in this report.

The strengthening technique by external cable prestressing, until now limited to columns with circular hollow sections (CHSs), is here extended to H-shaped steel columns. To provide an innovative general treatment, an initial imperfection, obtained from the analytical equivalence between Eurocode 3 and Ayrton–Perry formulations, is introduced. By this, a geometrically and materially nonlinear imperfection analysis (GMNIA) is performed by the finite element commercial code Abaqus. A parametric analysis identifies the deviator length, cable tension, and slenderness ratio as key parameters. Results confirm that, on the one hand, cable prestressing yields a critical load that is approximately twice that for non-prestressed elements (680 kN against 340 kN for a beam 8 m long); this effect grows with the column length. On the other hand, a simulation on a two-story frame supported by 12 columns, each 4 m long, spaced by 4 and 6 m in the two directions, under vertical ‘dead’ load shows that prestressed HEA200 columns perform as non-prestressed larger HEA220 profiles; thus, their use in this case leads to saving approximately 1.18 tons of steel; both these results are of practical interest in design of steel structures.

This article, written by Assistant Technology Editor Karen Bybee, contains highlights of paper SPE 97177, "From Geological Knowledge to Good Decisions Using Simple Stochastic Models, A North Sea Case Study," by K. Hollund, SPE, R. Hauge, SPE, and A.R. Syversveen, Norwegian Computing Center, and A. Jorstad, T. Lie, SPE, and H.C. Ronnevik, Lundin Norway A/S, prepared for the 2005 SPE Annual Technical Conference and Exhibition, Dallas, 9–12 October. The full-length paper details the stochastic model that was built to support decisions in the early phases of development of the Alvheim field. The model made it possible to explore important upside potential in geophysical evaluations and determine if and in what sequence additional wells should be drilled. An improved understanding of the value of different drilling strategies was gained by studying distributions for in-place oil and gas volumes for various scenarios. Introduction The approach to decisions detailed in the full-length paper is based on standard Bayesian decision theory that assigns a loss function to different decisions and then makes a decision rule on the basis of this loss function and the distribution of possible outcomes. The first step is universal in decision theory, and the second step is specifically Bayesian. Benefits of a simplified model include speed, flexibility, and ease of explanation. The challenge was to turn relatively small Paleocene structures consisting of unproven prospects and proven oil and gas reserves into a field development with a good economic performance. All field-development partners agreed that modeling the uncertainties of field development was important for establishing a good development strategy. The full-length paper details a simplified stochastic model built with a standard spreadsheet program and a Monte Carlo add-in to support decisions about the number and individual structures to be drilled. An improved understanding of the value of different appraisal strategies was gained by studying in-place oil and gas volumes for various scenarios. The model makes it possible to quickly compare expected values, uncertainty ranges, and other key variables for various scenarios. Alvheim Field The Alvheim field is in the PL203 License in the Norwegian North Sea and extends into the neighboring PL088 and PL036 Licenses. The field consists of three principal oil and gas discoveries—Kneler, Kameleon, and Boa—each of which contain hydrocarbons in good-quality Paleocene sandstones. A series of smaller accumulations that currently are not part of the development (Fig. 1) also occur in the area. In 1974, the first discovery in the area was a gas/oil accumulation in the Gekko structure that was drilled on the basis of 2D-seismic-data interpretation to test the extension of the Heimdal field. Oil and gas were found but were not considered economically feasible to develop. A small oil accumulation, Kobra, was found in 1997, and the gas/oil accumulation in the Kameleon structure was discovered in 1998. After this, the area lay dormant until it was acquired by the current operator in 2001.

API RP2A Load and Resistance Factor Design is a limit state design practice which is intended to replace the existing Working Stress Design practice for designing fixed offshore structures. Being in partial safety factor format, LRFD offers plenty of scope for influencing and improving design by calibrating the partial factors to suit regional environmental conditions and design practices. This paper presents the results from a joint industry project on the calibration of LRFD for Mediterranean Sea platforms. Advanced structural reliability methods formed the basis of the code calibration procedure which is briefly outlined. Probabilistic models for environmental and gravity loads and modelling uncertainties for tubular member and joint strength adopted in the reliability analysis are described. Comparisons of reliability indices for components designed under LRFD and WSD 18th Edition indicate that for the storm condition LRFDwould introduce a very small weight penalty whilst for the operating condition there would be a weight reduction. The application of LRFD would lead to significantly more uniform component reliability compared to WSD designs. Based on the proposed partial load factors for the MediterraneanSea the impact of LRFD to the design of jacket structures is assessed through verification studies of two typical platforms in the region. INTRODUCTION Regional variations in wave climate and design practice can be accounted for in LRFD-type design codes for offshore structures. The reliability based API RnA LRFD (Load andResistance Factor Design) [1], which has been proposed as an alternative to the Working Stress Design practice [2], takes into account the uncertainties associated with applied loads and structural component resistances and factors both loads and resistances. In contrast, in WSD only resistance factors are applied to derive allowable stresses. By explicitly defining partial factors for gravity and environmental loads it is possible to account for the variabilities in environmental conditions and design practices that exist worldwide. The partial load and resistance factors in the LRFD draft issue have been calibrated primarily for Gulf of Mexico structures [3]. Partial load factors for North Sea structures have beensubsequently proposed, based on the results of a joint industry project where advanced structural reliability methods were used for code calibration [4,5]. Following the conclusion of the North Sea adaptation the project was extended to adapt LRFD to the Mediterranean Sea [6]. Details of the underlying philosophy and procedures adopted for the calibration are given in [4]. This paper focuses on the work undertaken in the context of the Mediterranean Sea and presents the background information. Partial load factors for the in-place extreme and operating conditions have been derived using the same reliability based procedures to those adopted for the North Sea calibration. Based on the proposed load factors verification studies havebeen carried out for two typical jacket structures. The results are reported through comparisons of utilisation ratios for tubular members, legs and joints designed using LRFD and RP2A-18th Edition. They demonstrate potential effects of implementing LRFD to the Mediterranean Sea environment and highlight problem areas. Reference to the proposed LRFD version incorporatingrecommended Mediterranean Sea adjustments will be to LRFDMed.

API RP2A hot spot X and X' fatigue design curves for welded tubular connections have been replaced by a basic SN curve with slope m=3 changing to m=5 at ten million cycles. In this paper, the new criteria are compared with test data from both API-sponsored and European research -- including inter-related corrections for seawater, thickness, and use of weld profile control. Corrections for grinding and peening are also introduced, as well as SN curves and fatigue design requirements for cast nodes and grouted joints. The simple Alpha Kellogg SCF equations have been replaced by the more rigorous Efthymiou equations, with new adjustments for chord stress effects and weld toe position. Impact of the new revision, and some alternatives, on design practice and structural weight are examined. The Simplified Fatigue Design Procedure has been maintained, with the allowable peak hot spot stresses rechecked for the new CP-seawater SN curve. The API fatigue revisions have achieved better alignment with the ISO 19902 draft design procedures, without sacrificing the economy of existing practices. However, they are more complex. Designers will have a lot of new refinement to deal with, and having this background will help them understand it. Introduction Fatigue provisions in API RP2A were last updated in 1992, taking into account API-sponsored research from 1976–89 and a larger body of European work done primarily in 1978–87. That research re-affirmed the hot spot stress approach which had been in wide use since 1972, but refined it to include a more rigorous definition of the relevant stress, and to include the effects of random loading, of sea water environments, size, and profile. During the 1990s, API established the Offshore Tubular Joint Research Center jointly with the Edison Welding Institute and the Universities of Ohio and Illinois. OTJRC continued to review data on fatigue and static strength, and conducted new research in these areas. Unfortunately, their proposals for revision lay dormant because RP2A itself lay dormant for seven years, with most standardization efforts going into ISO. Most recently, API contracted with MSL Services to draft new tubular joint provisions. Their fatigue proposals largely follow DEn (UK) and ISO 19902 (North Sea) practices. MSL's draft provided clear and concise guidance, with many worthwhile improvements over the old API provisions. Their proposal reflects the international consensus and an intent to adopt back ISO-like provisions into API. The ISO 19902 draft and MSL proposal recognize no benefit for weld profiling. API Subcommittee 2 felt very strongly that some recognition of the benefit of weld profiling should be retained, keeping in step with AWS D1.1. The proposal also did not fully reflect the decade of corrosion-fatigue and weld profile research of Prof. Hartt at Florida Atlantic University, funded by API. With respect to the concept that both size and profile affect fatigue performance, there was a conflict between American practice and European orthodoxy. There were other technical issues that related to whether RP2A should represent American, North Sea, or broad international practice.

Mobil North Sea Limited recently brought the Galahad Platform into production in the North Sea UK Southern Sector Galahad is a minimum facility not normally manned production platform The platform was designed, procured, fabricated, installed and commissioned in approximately half the time of previous Southern Sector platforms. The work was completed between November 1994 and October 1995 at a considerably cost than previous developments. Several key learning areas were identified from the project including:Project Management applying the Principles of the CRINE (Cost Reduction Initiative in the New Era) processMinimum Facilities Installations - Comparison of Various ConceptsThe use of QRA (Quantified Risk Analysis) ]n Design DevelopmentThe Future of Minimum Facilities m the North Sea The Galahad Project was managed by Mobil using a small Project Task Force with two primary contractors working under EPIC type contracts. This style of management embraces the principles of the North Sea CRINE initiative where operators and contractors work in partnership complete projects in anefficient and timely manner. Another application of CRINE was to use an existing project design and previously established contractor project team. Several minimum facilities designs were considered for the development. The use of the monopod concept allowed for substantial reductions in topside weight, construction and installation cost compared with previous more conventional platforms. While designing the Galahad minimum facilities installation, our overall strategy was to reduce costs without compromising safety or reliability. Although not normally manned, the platform WIII be visited on average one day each month to perform routine maintenance. QRA was used to demonstrate that personnel working on the monopod installation would not be exposed to significantly higher levels of risk than are associated with four pile installations. QRA techniques were also employed in design development, accepting or rejecting safety features with the overall goal of developing a workplace where major hazards were prevented, controlled or mitigated to ensure that individual risks were as low as reasonably practicable. Introduction To competitively produce gas from the Galahad reservoir in the UK Sector of the Southern North Sea it was necessary to evaluate new cost effective methods of developing reserves, Galahad was the fourth field to be tied into the Lancelot Area Production System (1.APS) pipeline, Earlier phases of development were the Lancelot, Guinevere and Excalibur platforms, all of which are conventional four pile structures. Embracing the principles of CRINE Mobil North Sea Limited (MNSI.) was able to achieve significant cost savings during the Galahad project An existing Amoco monopod design was adapted to the for producing the Galahad reservoir By using the same design team and construction yard MNSL was able on experience gained during an earlier project. Quantified Risk Analysis (QRA) techniques were used in focusing expenditures to target areas where risk to personnel could be significantly reduced.

European smelt Osmerus eperlanus (n = 501) from the German Wadden Sea (North Sea) near the city of Cuxhaven were examined for their infestation with parasitic anisakid nematodes, especially with sealworms of the genus Pseudoterranova. The distribution of third-stage larvae (L3) in the musculature and viscera of the fish was analyzed. In total, we isolated 543 L3 from the hosts' body cavity and musculature. A subsample of 105 larvae were identified as the (sibling) species P. decipiens s.s. using direct sequencing of the highly variable ribosomal ITS1-5.8S-ITS2 genetic marker. The mean abundance was 1.1, the mean intensity was 2.3 P. decipiens s.s. and the prevalence was 47.3%. Total length and total weight, but not Fulton's condition factor (K), were significantly different in infected compared to uninfected smelt. No correlation was found between the total length of infected fish and the intensity of anisakid nematodes. The vast majority of P. decipiens s.s. was found in the musculature of the smelt. More than half (55.7%) of all nematodes were located in the 3 parts of the epaxial musculature, whereas 18.4 and 26.0% were found in the hypaxial musculature and the compartments of the tail muscles, respectively.