The Experts below are selected from a list of 489 Experts worldwide ranked by ideXlab platform
Jan Erik Vinnem - One of the best experts on this subject based on the ideXlab platform.
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Allision risk analysis of offshore Petroleum installations on the Norwegian Continental Shelf—an empirical study of vessel traffic patterns
WMU Journal of Maritime Affairs, 2017Co-Authors: Martin Hassel, Ingrid Bouwer Utne, Jan Erik VinnemAbstract:The Norwegian Petroleum Safety Authority (PSA) requires offshore Petroleum operators on the Norwegian Continental Shelf (NCS) to perform risk assessments of impacts (allisions) between passing ships and offshore installations. These risk assessments provide a basis for defining the allision accidental load that the installation shall be designed for. Even though the risk of allision is small, the potential consequences can be catastrophic. In a worst-case scenario, an allision may result in the total loss of an installation. The ageing industry standard allision risk model, COLLIDE, calculates the risk of impacts between passing (non-field-related) ships and installations based on Automatic Identification System (AIS) data. Both the COLLIDE risk model and a new Bayesian allision risk model currently under development are highly sensitive to variations in vessels’ passing distances, especially close proximity passings. Allision risk assessments are typically performed during the design and development phase of an installation, which means that historical AIS data are used “as is”, disregarding future changes to the traffic pattern when the new installation is placed on a location. This article presents an empirical study of one of the most important variables used to calculate the risk of allision from passing vessels, namely passing distance. The study shows that merchant vessels alter course to achieve a safe passing distance to new surface offshore Petroleum installations. This indicates that the results of current allision risk assessments are overly conservative.
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use of accident precursor event investigations in the understanding of major hazard risk potential in the norwegian offshore industry
Proceedings of the Institution of Mechanical Engineers Part O: Journal of Risk and Reliability, 2013Co-Authors: Jan Erik VinnemAbstract:The recent offshore accidents at the Macondo and Montara fields in the US and Australia have demonstrated the importance of learning from major accident precursors in order to appraise the risk potential involved in critical offshore operations. This is fully realised by the Petroleum Safety Authority in Norway, which has a specific requirement for such learning in its regulations. However, an unfortunate practice has been developed by the major players in the Norwegian offshore industry, whereby potential is severely and systematically downplayed, probably to limit the negative exposure if the actual potential consequences were known. The present article analyses 45 major accident precursor investigations in order to demonstrate the effect of downplaying the potential of major accidents. It demonstrates how the risk potential classified in investigation reports has a random relationship to the more objective risk potential, as shown in the national risk indicator project conducted by the Petroleum Safety Authority. This is further demonstrated by comparing company investigations with Authority investigations in four cases where parallel investigations were performed.
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use of accident precursor event investigations in the understanding of major hazard risk potential in the norwegian offshore industry
Proceedings of the Institution of Mechanical Engineers Part O: Journal of Risk and Reliability, 2013Co-Authors: Jan Erik VinnemAbstract:The recent offshore accidents at the Macondo and Montara fields in the US and Australia have demonstrated the importance of learning from major accident precursors in order to appraise the risk potential involved in critical offshore operations. This is fully realised by the Petroleum Safety Authority in Norway, which has a specific requirement for such learning in its regulations. However, an unfortunate practice has been developed by the major players in the Norwegian offshore industry, whereby potential is severely and systematically downplayed, probably to limit the negative exposure if the actual potential consequences were known. The present article analyses 45 major accident precursor investigations in order to demonstrate the effect of downplaying the potential of major accidents. It demonstrates how the risk potential classified in investigation reports has a random relationship to the more objective risk potential, as shown in the national risk indicator project conducted by the Petroleum Safety Authority. This is further demonstrated by comparing company investigations with Authority investigations in four cases where parallel investigations were performed. Language: en
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evaluation of the risk omt model for maintenance work on major offshore process equipment
Journal of Loss Prevention in The Process Industries, 2012Co-Authors: Bjorn Axel Gran, Ole Magnus Nyheim, E H Okstad, Jorunn Seljelid, Jorn Vatn, Snorre Sklet, Jan Erik VinnemAbstract:Abstract Operational Safety is receiving more and more attention in the Norwegian offshore industry. Almost two thirds of all leaks on offshore installations in the period 2001–2005, according to the Risk Level Project by the Petroleum Safety Authority in Norway, resulted from manual operations and interventions, as well as shut-down and start-up. The intention with the Risk OMT (risk modelling – integration of organisational, human and technical factors) program has been to develop more representative models for calculation of leak frequencies as a function of the volume of manual operations and interventions. In the Risk OMT project a generic risk model has been developed and is adapted to use for specific failure scenarios. The model considers the operational barriers in event trees and fault trees, as well as risk influencing factors that determine the basic event probabilities in the fault trees. The full model, which applies Bayesian belief networks, is presented more thoroughly in a separate paper. This paper presents the evaluation of the model. The model has been evaluated through some case studies, and one important aspect is the evaluation of the importance of each risk influencing factor. In addition some risk-reducing measures have been proposed, and the paper presents how the effect of these measures has been evaluated by using the model. Finally, possible applications and recommendations for further work are discussed.
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major hazard risk indicators for monitoring of trends in the norwegian offshore Petroleum sector
Reliability Engineering & System Safety, 2006Co-Authors: Jan Erik Vinnem, Jorunn Seljelid, Terje Aven, Torleif Husebo, Odd J TveitAbstract:Abstract The Petroleum Safety Authority Norway (PSA, formerly Norwegian Petroleum Directorate) took in 1999 the initiative to develop a method in order to assess trends and status for the risk levels in the Norwegian offshore Petroleum industry. A method was developed, and a pilot study report was issued in April 2001, covering the period 1996–2000. Annual updates have been performed since then, and the latest report covers the period 1996–2004. The statistical approach is based on recording occurrence of near misses and relevant incidents, performance of barriers and results from risk assessments. Of similar importance is an evaluation of Safety culture, motivation, communication and perceived risk. This is covered through the use of social science methods, such as questionnaire surveys and a number of interviews, audit and inspection reports as well as accident and incident investigations. There are also indicators for occupational accidents and occupational illness/-physical working environment factors. The focus is on the major hazard risk components for personnel staying on the offshore installations. An overview of the indicators used to illustrate these risk aspects is presented, followed by a discussion of the analytical approach used for these indicators. Results from the risk assessment for the Norwegian Continental Shelf in the period 1996–2004 are used throughout for illustration, and discussion of challenges.
Jan Erik Jensen - One of the best experts on this subject based on the ideXlab platform.
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the floatel superior loose anchor incident and its significance for design and operation of semi submersibles
ASME 2014 33rd International Conference on Ocean Offshore and Arctic Engineering, 2014Co-Authors: Terje Leenhart Andersen, Arne Kvitrud, Jan Erik JensenAbstract:The combination of dynamic positioning (DP) and conventional anchoring of semi-submersible platforms in the oil industry has recently lead to a serious incident with large loss potential: the Floatel Superior platform suffered severe damage to its hull from a loose anchor in heavy seas during the night of November 6th–7th, 2012. This paper discusses the root causes leading to the incident. The investigation report from the Petroleum Safety Authority Norway (PSA) concludes that damage leading to the loose anchor had developed over several months, and various warning signs during that period were not heeded. The main reason for the damage was rooted in the combined operation mode where position-keeping by use of DP resulted in large environmental loads on the anchors while they were stowed in their bolsters along the vessel side in rough weather when the installation was at survival draught and operating on DP. The anchors on Floatel Superior had also been exposed to environmental loads in excess of the design capacity during extended transit two years prior to the incident. The incident itself was handled efficiently by the crew and emergency preparedness organizations, with 336 people evacuated by helicopter and the remaining 38 crew members transporting the damaged vessel to shore for repairs.In this paper, an immediate recommendation for removing anchors from the splash-zone while operating on DP is presented as relevant for other installations with similar class notation. In a longer perspective, the investigation found that both well-established design codes and their application in the actual design had shortcomings which played a role in the cause of events. The vessel design appears to have been performed with a principal focus on sub-units (anchor, winch, bolster, pendant-wire attachment) and to an insufficient extent on the combined system use under which it was to be operated. A long-established method of design for connections of auxiliary structures to the main hull structure also showed shortcomings in the event: the doubler plates or pads used to attach the bolsters to the hull did not function as weak links as intended.© 2014 ASME
Terje Leenhart Andersen - One of the best experts on this subject based on the ideXlab platform.
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the floatel superior loose anchor incident and its significance for design and operation of semi submersibles
ASME 2014 33rd International Conference on Ocean Offshore and Arctic Engineering, 2014Co-Authors: Terje Leenhart Andersen, Arne Kvitrud, Jan Erik JensenAbstract:The combination of dynamic positioning (DP) and conventional anchoring of semi-submersible platforms in the oil industry has recently lead to a serious incident with large loss potential: the Floatel Superior platform suffered severe damage to its hull from a loose anchor in heavy seas during the night of November 6th–7th, 2012. This paper discusses the root causes leading to the incident. The investigation report from the Petroleum Safety Authority Norway (PSA) concludes that damage leading to the loose anchor had developed over several months, and various warning signs during that period were not heeded. The main reason for the damage was rooted in the combined operation mode where position-keeping by use of DP resulted in large environmental loads on the anchors while they were stowed in their bolsters along the vessel side in rough weather when the installation was at survival draught and operating on DP. The anchors on Floatel Superior had also been exposed to environmental loads in excess of the design capacity during extended transit two years prior to the incident. The incident itself was handled efficiently by the crew and emergency preparedness organizations, with 336 people evacuated by helicopter and the remaining 38 crew members transporting the damaged vessel to shore for repairs.In this paper, an immediate recommendation for removing anchors from the splash-zone while operating on DP is presented as relevant for other installations with similar class notation. In a longer perspective, the investigation found that both well-established design codes and their application in the actual design had shortcomings which played a role in the cause of events. The vessel design appears to have been performed with a principal focus on sub-units (anchor, winch, bolster, pendant-wire attachment) and to an insufficient extent on the combined system use under which it was to be operated. A long-established method of design for connections of auxiliary structures to the main hull structure also showed shortcomings in the event: the doubler plates or pads used to attach the bolsters to the hull did not function as weak links as intended.© 2014 ASME
Odd J Tveit - One of the best experts on this subject based on the ideXlab platform.
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major hazard risk indicators for monitoring of trends in the norwegian offshore Petroleum sector
Reliability Engineering & System Safety, 2006Co-Authors: Jan Erik Vinnem, Jorunn Seljelid, Terje Aven, Torleif Husebo, Odd J TveitAbstract:Abstract The Petroleum Safety Authority Norway (PSA, formerly Norwegian Petroleum Directorate) took in 1999 the initiative to develop a method in order to assess trends and status for the risk levels in the Norwegian offshore Petroleum industry. A method was developed, and a pilot study report was issued in April 2001, covering the period 1996–2000. Annual updates have been performed since then, and the latest report covers the period 1996–2004. The statistical approach is based on recording occurrence of near misses and relevant incidents, performance of barriers and results from risk assessments. Of similar importance is an evaluation of Safety culture, motivation, communication and perceived risk. This is covered through the use of social science methods, such as questionnaire surveys and a number of interviews, audit and inspection reports as well as accident and incident investigations. There are also indicators for occupational accidents and occupational illness/-physical working environment factors. The focus is on the major hazard risk components for personnel staying on the offshore installations. An overview of the indicators used to illustrate these risk aspects is presented, followed by a discussion of the analytical approach used for these indicators. Results from the risk assessment for the Norwegian Continental Shelf in the period 1996–2004 are used throughout for illustration, and discussion of challenges.
Arne Kvitrud - One of the best experts on this subject based on the ideXlab platform.
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the floatel superior loose anchor incident and its significance for design and operation of semi submersibles
ASME 2014 33rd International Conference on Ocean Offshore and Arctic Engineering, 2014Co-Authors: Terje Leenhart Andersen, Arne Kvitrud, Jan Erik JensenAbstract:The combination of dynamic positioning (DP) and conventional anchoring of semi-submersible platforms in the oil industry has recently lead to a serious incident with large loss potential: the Floatel Superior platform suffered severe damage to its hull from a loose anchor in heavy seas during the night of November 6th–7th, 2012. This paper discusses the root causes leading to the incident. The investigation report from the Petroleum Safety Authority Norway (PSA) concludes that damage leading to the loose anchor had developed over several months, and various warning signs during that period were not heeded. The main reason for the damage was rooted in the combined operation mode where position-keeping by use of DP resulted in large environmental loads on the anchors while they were stowed in their bolsters along the vessel side in rough weather when the installation was at survival draught and operating on DP. The anchors on Floatel Superior had also been exposed to environmental loads in excess of the design capacity during extended transit two years prior to the incident. The incident itself was handled efficiently by the crew and emergency preparedness organizations, with 336 people evacuated by helicopter and the remaining 38 crew members transporting the damaged vessel to shore for repairs.In this paper, an immediate recommendation for removing anchors from the splash-zone while operating on DP is presented as relevant for other installations with similar class notation. In a longer perspective, the investigation found that both well-established design codes and their application in the actual design had shortcomings which played a role in the cause of events. The vessel design appears to have been performed with a principal focus on sub-units (anchor, winch, bolster, pendant-wire attachment) and to an insufficient extent on the combined system use under which it was to be operated. A long-established method of design for connections of auxiliary structures to the main hull structure also showed shortcomings in the event: the doubler plates or pads used to attach the bolsters to the hull did not function as weak links as intended.© 2014 ASME