risk management news - riskspectrum - scandpower management news/risk...risk management news 2-2009...

SCANDPOWER

R i sk Management News

CONTENTS

Issue 2 - 2009

Scandpower at Nordic Rail Fairp. 9

Cooperation Agreement with ComputITpp. 4-5

Focus on R&D pp. 11-13

Arctic Challengesp. 3

Phot

o: L

eif J

ohnn

y O

lest

ad

2 Risk Management News 2-2009

Risk Management News is published by Scandpower and distributed to some 8,000 subscribers in 72 countries.

For a free subscription, see our website www.scandpower.com

Contact us: Scandpower AS P.O. Box 3 NO-2027 Kjeller, Norway

Editor-in-Chief Bjørn Inge Bakken CEO, Scandpower Group [email protected]

Editor Inge Asgeir Alme Vice President, Scandpower Group [email protected]

Associate Editors and Design Elisabeth Schiørn, Ståle Nilsen

Language Consultant Victoria Coleman

Printing HTR, www.htr.no

The Hywind Demo WTG was successfully installed 12 km off the island of Karmøy near Stavanger, Norway, on June 8, 2009. The Hywind Demo is the first full-scale floating wind turbine in the world. The concept is wholly owned by StatoilHydro, whose ambition is to develop a new business area within offshore wind.The ground-breaking Hywind design is the result of a combination of wind power expertise and StatoilHydro’s extensive offshore experi-ence. Hywind features rotor blades with a diameter of 80 meters – approximately the length of a jumbo jet – and the nacelle is mounted some 65 meters above the sea surface, while the floatation element extends 100 meters below the surface and is moored to the seabed using three anchor piles.

The wind turbine itself is an off-the-shelf 2.3 MW turbine manufac-tured at Siemens Wind Power’s facilities in Denmark. Technip built the floatation element at the Technip Pori Yard in Finland, transporting it as a wet tow using tugs to the western coast of Norway and installing it. Nexans manufactured and installed the 13-km-long subsea cable to shore, while Haugaland Kraft provided the landfall.

The objective of the Hywind Demo R&D project is to cut the cost of offshore wind power generation. A two-year testing period will start in the autumn of 2009.

Scandpower is responsible for the HSE work in all phases of the Hywind Demo project, from engineering, construction and installa-tion to commissioning and operation. Offshore wind is an expanding market where Scandpower sees considerable potential for growth in the years to come.

[email protected]

Hywind Demo Next-Generation Wind Technology Ph

oto:

Øyv

ind

Hage

n / S

tato

ilHyd

ro

The summer holidays are behind us and we are back to our daily routine. I hope each and every one of you has had a peaceful and relaxing holiday.

In recent months there has been a shaky upswing in the stock market and the price of oil has been hovering around USD 60–70 a barrel. Nevertheless, there is no cause to relax. The market situation will remain tough and turbulent in the coming months – maybe even in the coming years – and players in the energy market will continue to operate in a very competitive environment.

We must find better, more efficient ways of working in this environment. But we must do so without compromising quality, health and safety.

The global demand for energy will continue to rise, driven by de-velopments in China, India and other up-and-coming economies. Meanwhile, focus on climate-friendly energy sources is growing and the fleet of nuclear installations and oil production facilities is ageing rapidly. All this adds up to significant growth potential for companies in the energy market in the years to come.

We are seeing a boost in activity relating to renewable energy sources such as wind, solar and hydropower, as well as to car-bon capture, transport and storage. Within the oil & gas sector, major challenges revolve around development in deepwater, Arctic and HPHT field developments, and there is increasing focus on the optimization of existing facilities and the develop-ment of marginal fields with tie-back to existing infrastructure.

We are also witnessing a nuclear renaissance, with a potential doubling of the number of nuclear plants worldwide. There are currently 48 plants under construction, 133 plants under plan-ning, and an additional 282 plants have been proposed. To top it off, a number of large-scale projects are underway relating to life prolongation and upgrades of the existing fleet of nuclear power plants, which have an average age of about 30 years. Realizing even a fraction of these ambitious projects will put tremendous pressure on capacity and capability.

Scandpower is in an excellent position to face these challenges head on. But perhaps our greatest challenge will be to recruit a sufficient number of dedicated, highly skilled professionals to the Scandpower team.

Bjørn Inge BakkenCEO, Scandpower Group

Risk Management News 2-2009 3

Scandpower is involved in several large field developments in the Arctic region where extreme conditions present major challenges to ensuring safe operations for oil and gas exploration and production.

In certain areas, 1 to 1.5-m-thick pack-ice presents a challenge to exploration and production several months a year, while severe wave conditions and significant earthquake activity pose challenges year round. In addition, stringent requirements must be met regarding the winterization of oil and gas facilities to withstand ultra-low tempera-tures, and extreme wind and snow conditions.

Due to the harsh environmental conditions, platform concepts with closed or partly closed modules are considered to be the most appro-priate for providing personnel and drilling and production equipment with adequate protection from the elements. There are problems, however, with using closed modules when it comes to handling gas leaks and the risk of fire and explosion.

Scandpower has been involved in several large-scale projects to analyze the effects of using closed modules. The company has utilized advanced Computational Fluid Dynamics (CFD) modeling – including the state-of-the-art CFD tools Kameleon FireEx KFX® and FLACS – to model gas dispersion, internal and external fires, explosions and smoke dispersion for a number of potential scenarios in order to investigate the effects on installations and personnel. The studies are being used to optimize platform designs to ensure safe, reliable operations in the demanding Arctic climate.

Probabilistic modeling of fire and explosion loads, as well as optimi-zation of active and passive risk mitigating measures have been key elements in Scandpower’s work. In this context, risk mitigating mea-sures include configuration of fire and gas and emergency shutdown systems, ventilation system control, ignition sources control, area segregation, and active and passive fire protection systems.

Scandpower has also performed a generic explosion risk study for Arctic platform concepts in collaboration with StatoilHydro’s research department, based on Scandpower’s in-house tool for probabilistic

explosion risk modeling. The project resulted in an alternative to a closed module design, which may reduce explosion risk while at the same time providing a satisfactory working environment in Arctic areas. The concept features rotating wall elements, which, when gas is detected, have the potential to reduce the strong explosion frequency by a factor of three compared to closed module designs. Scandpower presented the research at the Ninth SPE International Conference on Health, Safety, and Environment in Oil and Gas Explo-ration and Production held in Nice, France, on April 15-17, 2008. (The complete paper is available at www.scandpower.com.)

Thanks to the extensive expertise generated during the project, Scandpower can provide the oil and gas industry with high-quality decision-making support on technical safety issues in Arctic environments.

[email protected]

Phot

o: Ø

yvin

d Ha

gen

/ Sta

toilH

ydro

Arctic Challenges


Scandpower and ComputIT Sign Strategic Cooperation AgreementFollowing several years of successful collaboration Scandpower and ComputIT signed a strategic cooperation agreement on July 1.“The cooperation agreement paves the way for further development and use of the Computational Fluid Dynamic software Kameleon FireEx KFX® within the risk management area,” says Trond Evanger, Managing Director of ComputIT AS.

“Securing access to this advanced CFD software and ComputIT’s expertise and resources is essential to our further development within this area. Today Scandpower has about 25 professional users of KFX, and we are seeing an overall increase in the use of CFD tools within the company,” adds Bjørn Inge Bakken, CEO of the Scandpower Group.

Thanks to advances in computer hardware and more efficient simula-tion models, advanced CFD tools are being chosen more and more often over to simplified empirically-based software tools. There is now a lower threshold for performing consequence simulations using CFD and finite element models.

Typical areas of application for KFX within risk management include:

•Dispersion of flammable or toxic gases

•Exhaust gas and smoke dispersion calculation

•Wind turbulence problems, e.g. related to helicopter traffic, etc

•Wind chill and working environment aspects

•Determination of accidental loads during fires

•Optimization of fire protection measures, e.g. passive and active fire protection systems

•Flare analysis and design

•Advanced ventilation simulations

The results of KFX fire simulations may also be linked to structural finite element models to analyze structural response to fire loads. Given the nearly unlimited number of potential fire scenarios at an individual plant, a probabilistic approach is often applied to deter-mine the dimensioning of accidental loads. (See the related article on USFOS software on page 6.)

Today Scandpower uses KFX within all its market segments: the oil and gas industry, the nuclear industry, and the transport industry (e.g. in connection with road tunnel fires).

“The cooperation agreement will also provide valuable input for the further development of KFX in the years to come,” concludes Trond Evanger.

[email protected]

Trond Evanger (ComputIT), Ingar Fossan (Scandpower), Bjørn F. Magnussen (ComputIT), Bjørn Inge Bakken (Scandpower), Øystein Spangelo (Scandpower).

Screenshot of a sample KFX user interface.

Phot

o: M

ats

Bakk

en


The Father of KFXProfessor emeritus Bjørn F. Magnussen, Chairman of the Board of ComputIT, is the grand old man of combustion technology and the “father” of Kameleon FireEx KFX®. He is very pleased with the signing of the cooperation agreement with Scandpower.Professor Magnussen began his study of turbulence nearly 50 years ago, and this evolved into the renowned Eddy Dissipation Concept for mathematical modeling of turbulent combustion. In the late 1970s Magnussen directed his focus toward fire safety in the oil and gas industry, setting into motion the development of KFX and initiating extensive cooperation with the industry. In 1995 he was awarded Statoil’s research prize for his contribution to the development of the Norwegian oil and gas industry.

Professor Magnussen’s hope is that the cooperation agreement be-tween ComputIT and Scandpower will help to create a safer working environment and reduce risk associated with capital investment.

• Company specializing in CFD modeling of turbulent flow

and combustion

• Founded in 1999 as a spin-off from the Norwegian

University of Science and Technology (NTNU) and the

SINTEF Research Group

• Based in Trondheim and Stavanger, Norway

• Managing Director – Trond Evanger

• 15 specialists within CFD modeling

• Main product: CFD software Kameleon FireEx KFX®

• 40 % of turnover related to R&D

• Recently bought the company CFD Norway AS, which spe-

cializes in CFD simulation of all types of external flows

• Strategic cooperation with StatoilHydro, Total, ENI, Cono-

coPhillips and Gaz de France, and close cooperation on

projects with other major oil and gas and engineering

companies

• Also specializes in combustion modeling for environmental

analysis and optimal design of burners, incinerators, flares

etc

• Read more at www.computit.no

ComputIT

“Statoil has actively supported the devel-opment of KFX over the past 20 years, and it is our preferred CFD software tool for advanced fire modeling.”

“My hope is that the cooperation agree-ment between Scandpower and ComputIT will enhance the further development of KFX and increase the overall use of KFX in the market, ultimately resulting in more optimal fire-safety solutions.”

Jens K. Holen, Specialist, StatoilHydro’s department for safety technology.

StatoilHydro Actively Supports KFX

Phot

o: M

ats

Bakk

en


Structural Response to Accidental Loads

To further enhance the company’s capabilities in risk evaluation and fire simulation for fire response of structures, Scandpower has acquired the advanced software tools USFOS and FAHTS.USFOS is a leading computer program for nonlinear static and dynamic analysis of space frame structures. The program accurately simulates the collapse process, from the initial yielding, through to the formation of a complete collapse mechanism and the final toppling of the structure.

USFOS is an acronym for Ultimate Strength for Offshore Structures. Scandpower will primarily use the tool for analyses and predictions of optimal application of passive fire protection on structural steel frames. USFOS can also be used to communicate the necessity of improved process segregation to reduce the extent and duration of potential fires.

To fully exploit the features of the computer program, it is essential to carry out a thorough evaluation of the risk picture and define poten-tial design fire scenarios before commencing structural analyses. This must be done at an early stage of the project in close cooperation with the client.

Scandpower uses the fire and gas dispersion simulator Kameleon FireEx KFX® to compute fire simulations. “Time dumps” from the KFX simulations describe the transient time/space heat exposure from the design fires and are imported automatically via FAHTS into the geometrical model of the steel structure in USFOS. FAHTS (Fire and Heat Transfer Simulation) is a nonlinear time domain heat transfer code. The structural model is automatically transferred to surface shell elements in FAHTS in order to acquire the correct heat flux and cap-ture thermal gradients over the cross-section resulting from uneven fire exposure and/or partly protected members. The heat exposure, expressed as radiation heat flux and convective heat flux, varies from point to point on the structure depending on the relevant point’s

coordinates and surface orientation, i.e. whether its surface is facing toward or away from the fire.

Passive fire protection (PFP) may involve selected structural elements, depending on the unprotected structure’s degree of heat and me-chanical utilization. The thermal insulation effect is expressed in terms of the generic effective Heat Transfer Coefficient (W/m2K), often denoted as U-value.

Based on the simulated heat loads from the fire, USFOS calculates the structural response to the temperature rise in the structure and the applied mechanical loads. In addition to optimizing the use of PFP, such full-scale virtual testing generates valuable information for designing structures that are less vulnerable to heat, i.e. for creating more redundant systems.

[email protected]

Projected temperatures in KFX simulation of a pool fire.

Mechanical response of steel frame exposed to the pool fire.

Temperatures at specific times in steel frame exposed to the pool fire.


To supplement the company’s software toolbox for consequence modeling, Scandpower has acquired the PIPENET™ Transient Module. This software tool is specifically designed for hydraulic analysis of incompressible single-phase fluid flow in pipe networks. It is intended to complement OLGA® – Scandpower’s preferred software for multi-phase fluid flow – which has limitations when it comes to handling incompressible liquid flow.The company recently utilized PIPENET™ to analyze the consequences of an emergency shutdown during offloading from a FPSO. A valve downstream in the offloading system was closed to deliberately cause a large pressure surge in the piping. PIPENET™ was then used to verify whether the overpressure exceeded the design pressure of the piping in the offloading system.

PIPENET™ can also be applied to a wide range of safety-related studies. For instance, Scandpower has used PIPENET™ to perform firewater systems analysis in accordance with NORSOK S-001 and NFPA standards.

[email protected]

Screenshot of a sample PIPENET™ user interface.

Dr. Jørgen Amdahl is a professor in the Department of Marine Technology at the Norwegian University of Science and Technology (NTNU) in Trondheim.Dr. Amdahl was instrumental in the development of the nonlinear finite element program USFOS, which is widely used by the offshore industry to design structures that can withstand extreme and accidental loads. He was also primarily responsible for the development of NORSOK STANDARD N-004 for Offshore Structures, Appendix A: Accidental Actions, and contributed to the development of ISO 19901-3 Topside Structures regarding requirements for offshore topside structures subjected to accidental actions. He is the co-author of the book Nonlinear Analysis of Offshore Structures (Baldock, Hertfordshire, England: Research Studies Press Ltd., 2002).

Dr. Amdahl’s consultancy company, Amdahl ALS Engineering, and Scandpower have signed an agreement for the provision of technical assistance to Scandpower in cases where there is a need for external analysis work involving USFOS.

Jørgen Amdahl and Scandpower Sign Cooperation Agreement

Dr. Jørgen Amdahl.

Hydraulic Analysis of Fluid Flow


Human Factors Analysis of the Vessel Traffic Centers in SwedenThe Swedish Maritime Administration is responsible for the operation of vessel traffic centers in Sweden. The Vessel Traffic Service (VTS) encompasses a range of services, including maritime traffic information in busy or environmentally vulnerable areas. Its purpose is to increase maritime traffic safety and prevent damage to the environment.

The Swedish Maritime Administration has established nine VTS areas along the Swedish coastline. Vessels are required to notify the VTS center in the relevant area and provide identification and destination information, etc. In return the vessel receives information about other vessels’ movements and difficult passages.

The Swedish Maritime Administration has enlisted Relcon Scandpower to assist in its efforts to improve and streamline its services and create a basis for the VTS centers’ future activities and organization.

Relcon Scandpower is carrying out a feasibility study to map and document the functions and current status of the Södertälje, Luleå and Gothenburg VTS centers. The centers’ central and local functions are being mapped to identify which functions are directly VTS-related and which are not, and to ascertain which are working well and which are not. The operators’ current work situation – as experienced

by the operators themselves – is also being documented, as the incor-poration of a human factors perspective will provide a broader, more accurate picture of the VTS centers’ functionality.

Interviews and observations of operational activities have been an integral part of the first phase of the project, during which Relcon Scandpower has visited each center and performed conformed situation and function analyses.

[email protected]@relconscandpower.com

Gothenburg VTS center.

Phot

o: P

er C

hrist

offe

rson

Phot

o: P

er C

hrist

offe

rson


Common Safety Methods for the European Rail IndustryConstructing a modern integrated railway network is a top EU priority. This will be a major challenge, as the lack of standardization has led to the development of different risk management principles and approaches in countries across Europe.

It will obviously be difficult to create an international rail transport system in a community with a variety of safety cultures. In light of this, the European Railway Agency (ERA) is establishing a common approach to railway safety and interoperability that will hopefully facilitate the growth and development of both passenger and freight transport.

To enable interoperability, signaling standards have been drawn up as part of the European Rail Traffic Management System (ERTMS). Meanwhile, Technical Specifications for Interoperability (TSI) are gradually being established. The absence of a common approach for specifying and demonstrating compliance with safety levels and requirements has proven to be yet another obstacle to liberalizing the railway market. A Common Safety Method (CSM) for risk evaluation and assessment has therefore been defined to harmonize methods for identifying and managing risk.

Visit Scandpower at Rail Fair in SwedenScandpower will be participating at Nordic Rail, a renowned fair organized by the Nordic railway industry every two years.The fair will be held this year on October 6-9 at Elmia Fairs in Jönköping, and major players in the European rail sector are expected to attend. The fair gives participants an excellent opportunity to make new contacts, get up to date with current developments and gain inspiration. In addition to the exhibition, some 100 seminars will be held in the course of three days.

Scandpower is seeking to repeat its success from 2007 and will have a stand in Hall D where you can meet personnel from both Sweden and Norway.

[email protected]

The ERA is collaborating with railway sector stakeholders on the development of the CSM. Dissemination activities are underway in the form of workshops in which Scandpower is participating as a Notified Body.

The application of the CSM will be required in cases of significant technical, operational and organizational change in a railway system. The intention is to streamline the risk assessment process, which is typically an iterative process comprising:

• Systematic identification of hazards

• Risk analysis and risk evaluation

• Demonstration of system compliance

The implementation of a hazard management process and an inde-pendent assessment by an assessment body of whether the overall CSM process has been correctly applied will also be required.

The CSM Regulation is due to come into effect on July 19, 2010 for significant changes affecting vehicles and rail systems and on July 1, 2012 for operational and organizational changes.

[email protected]

www.elmia.se/nordicrail

Facts about Nordic Rail (2007)

No. of visitors: 4,872

No. of exhibitors: 236

No. of countries: 19

Total exhibition area: 6,383 m3

Phot

o: E

lisab

eth

Schi

ørn

Phot

o: P

er C

hrist

offe

rson


Design Requirements and Safety Strategies for Onshore Plants

A well-established safety strategy for handling potentially hazardous scenarios is a vital tool for maintaining an adequate level of safety for personnel, the environment and material assets at onshore plants. In June 2007 StatoilHydro engaged Scandpower to assist in drawing up the safety strategy document for the Tjeldbergodden industrial plant. Scandpower is currently undertaking similar projects for the Mongstad production plant, the Sture crude oil terminal and the Kalundborg oil refinery.

According to Alison Catherine Sørensen, project manager at StatoilHydro Kalundborg, and Rita Waagenæs, project manager at StatoilHydro Mongstad, the primary concern is to ensure that the level of technical safety at the plants complies with StatoilHydro’s HSE and risk management standards. The safety strategies are based on a pre-defined set of performance standards and present design require-ments for technical safety barriers for future plant modification and expansion projects. The strategies also describe the role and state of current safety barriers in the existing plants and propose improvement measures where weaknesses have been identified.

Collecting this type of information requires considerable knowledge of the plants, which Scandpower has acquired by conducting inter-views with key personnel. Questionnaires regarding the performance standards in StatoilHydro’s governing document TR2237 “Safety Design for Onshore Plants”, along with other important technical data sources such as Total Risk Analysis (TRA), Emergency Preparedness Analysis (EPA), periodical Plant Audit reports on the condition of safety barriers (TTS), system descriptions etc., have formed the basis for the interviews, and have also played a vital role in discussions.

In general, design requirements at all the plants comply with StatoilHydro’s performance standards. In some cases, however, distinctive plant characteristics make it necessary to define alternative, plant-specific requirements. Such alternative requirements and appurtenant compensatory safety measures must be processed and approved by StatoilHydro’s central HSE management before they may be implemented.

[email protected]@scandpower.com

Kalundborg


Scandpower’s office in Houston, Texas, recently signed a research agreement with the University of Maryland (UoM) and its Reliability Engineering Program. Under the agreement, Scandpower will offer students internships within the area of risk and reliability analysis with emphasis on nuclear safety applications.

In August 2009 Ms. Danielle Chrun (a UoM PhD candidate) began a six-month internship under the supervision of Professor Ali Mosleh (UoM) and Mr. Bengt Lydell (VP Nuclear Services, Scandpower Houston). During her internship, Danielle will work on assignments within the area of passive component reliability and its relationship to the incorporation of time-dependent aging effects into probabilistic safety assessments (PSA). These assignments are closely related to ongoing, long-term Scandpower projects that address the develop-ment of methods and techniques for improving the assessment of the effects of time-dependent degradation mechanisms on the structural integrity of metallic piping components. The results of Danielle’s work are planned to be published in archival journals such as Nuclear Engineering and Design and System Safety & Reliability Engineering.

[email protected]

Research Agreement with the University of Maryland

Glenn L Martin Hall (home of the Reliability Engineering Program) on the UoM

College Park (MD) Campus.

Focus on R&D

Cooperation with Uppsala University

Seniors in the Master’s Program in Socio-technical Systems Engineering at Uppsala University in Sweden have the opportunity to take a specialized course in risk management at the Faculty of Science and Technology. The course is a collaborative effort between the university and Relcon Scandpower, and is partially funded by the Swedish Radiation Safety Authority.

The course has two areas of focus: Probabilistic Safety Analysis (PSA) and Human Factors (HF). In addition to attending traditional lectures, students, in groups of four or five, conduct a three-week project in either the PSA or the HF field. Relcon Scandpower’s contribution to the course consists of lectures on HF and the use of RiskSpectrum® software. The company also offers students guidance during the project period and evaluates project reports.

As part of PSA-related projects, students perform a complete fault tree analysis on typical subsystems at nuclear power plants, such as the auxiliary water feed system and the safety injection system. Students are required to collect the information needed to design an appropriate fault tree and to carry out both a qualitative and a quantitative analysis of the fault tree. RiskSpectrum® software is their main tool.

HF-related projects are conducted in cooperation with companies in Relcon Scandpower’s network. This year, for example, Eka Chemicals and the Swedish Maritime Administration offered their time and resources, giving students the opportunity to gain insight into their activities and helping them analyze problems from a human factors perspective. The projects brought the students out of the ivory tower and into the real world, where they could try on the role of consultant for a couple of weeks. The companies also benefited from the projects. According to Henrik Staberg, technical manager at Eka Chemicals, “The students we hosted in Bohus did a professional and thorough job, and their report gave us interesting material to work with.”

Thanks to its collaboration on the course, Relcon Scandpower is a well-known name among senior Master’s students at Uppsala University and the company has been able to attract a number of new recruits in the past few years.

Planning of next year’s course is already underway.

[email protected]

Phot

o: P

erer

ic Ö

berg


Reliability Data Handbook for Piping Components in Nordic Nuclear Power PlantsRelcon Scandpower is developing a handbook for assessing piping reliability parameters, primarily for use in nuclear probabilistic safety assessment (PSA). The project has been underway for well over 10 years and has gone through various phases. The actual work on reliability parameter calculation started in 2008 and the first version of the handbook is expected to be finalized during 2009.

The Reliability Data Handbook (the R-book) will contain rupture frequencies for different leakage threshold values for pipes according to initial defects, pipe size, type of piping components and materials. Many factors may vary; thus the specific rupture frequency must be calculated for a large number of cases.

The approach is based on Bayesian methodology and is similar to the concept of the T-book (Component Reliability Data Handbook for Nordic NPPs). After identifying which degradation mechanisms are valid (under which conditions) for the various systems in the plant, the failure frequency can be assessed. This is done by defining a prior distribution and updating it with the statistics of pipe failure events from the OPDE database (OECD Pipe Failure Data Exchange Project). The OPDE database contains worldwide service experience data for pipe failure events. The Bayesian analysis calculations are performed using R-DAT Plus, which is a Bayesian data analysis package for risk analysts.

Since the rupture frequencies are calculated for different flow rates it is possible to implement pipe rupture for different Loss of Coolant Accident (LOCA) categories in the PSA. The number of components, e.g. welds, in a subsystem is multiplied by the rupture frequency given in the R-book to generate the total failure frequency per year for the subsystem.

The R-book project is financed by the Nordic PSA Group (NPSAG), and is led by Relcon Scandpower in Sweden in cooperation with Scandpower’s office in Houston, Texas.

[email protected] [email protected]

NKS (Nordic Nuclear Safety Research) is a platform for Nordic cooperation and competence in nuclear safety, including radiation protection and emergency preparedness. It is an informal forum, serving as an umbrella for Nordic initiatives and interests. Its purpose is to carry out joint activities producing seminars, exercises, scientific articles, technical reports and other types of reference material. The work is financed and supported by Nordic authorities, companies and other organizations. The results are used by participating organizations in their decision-making processes and information efforts.

The Nordic PSA Group NPSAG was founded in December 2000 by the nuclear utilities in Finland and Sweden. In addition, the Swedish Radiation Safety Authority (SSM) participates as an observer, and also takes part in the funding of many of the projects. NPSAG is intended to be a common forum for discussion of issues related to probabilistic safety assessment (PSA) of nuclear power plants, with focus on research and development needs. The group follows and discusses current issues related to PSA nationally and internationally, as well as PSA activities at the participating utilities. The group initiates and coordinates research and development activities and discusses how new knowledge shall be used.

Focus on R&D


As part of a Nordic project dealing with the use of probabilistic safety criteria for nuclear power plants, a comparison was made with risk criteria used in the European railway industry and the offshore oil and gas industry. Carried out by Relcon Scandpower and VTT Technical Research Centre of Finland, the project was initiated by NKS (Nordic Nuclear Safety Research) and the Nordic PSA Group NPSAG. It also shares links to the OECD Nuclear Energy Agency’s (NEA) work involving probabilistic safety criteria in the NEA member countries.

Safety goals for nuclear power plants are defined in different ways in different countries and implemented in different manners. Many countries are currently developing safety goals in connection with the transition to risk-informed regulation of nuclear power plants already in operation and new designs. Risk criteria are defined at various levels, from societal and individual risk to off-site radioactive release, reactor core damage and lower-level system reliability. Subsidiary criteria, on the other hand, are primarily defined at the level of core damage and large radioactive release frequency. Risk criteria have a different status in different countries. Several countries operate with strict regulatory limits, while most countries use indicative target values. The status of existing plants and new plants may also vary. A number of countries apply the ALARP principle, which involves risk criteria with associated limits and objectives.

The survey of risk acceptance criteria in the offshore oil and gas industry focused on Norwegian and UK requirements. In this in-dustry both qualitative and quantitative risk acceptance criteria are used to express a risk level with respect to a defined period of time or phase of activity. Both the number of precursor events requiring handling and the number of accidents requiring mitigation are high compared to the nuclear industry. Accordingly, the criteria have a relatively strong focus on consequence mitigation. The criteria also have a broad scope, covering a range of accident events and safety functions. There is also greater focus on the various operating phases (design, construction, operation, maintenance and decommissioning) than in the nuclear industry. With regard to defense in depth, the criteria stipulate requirements for various safety functions. As in the nuclear industry, the ALARP principle is often applied.

For railway systems, the survey focused on risk criteria defined for the European Train Control System (ETCS). There is a high degree of standardization in the railway industry to enable trains and personnel to cross national borders. Harmonization has been achieved by letting an industry working group propose risk criteria that are subsequently approved by the authorities. The proposed criteria comprise consen-sus requirements based on an amalgamation of national practices, mainly from Germany and France, with basic principles relating to general health risk (the MEM principle) and continuous safety im-provement (the GAMAB principle). Systematic procedures are in place for creating subsidiary goals by defining a tolerable hazard rate (THR) for the individual subsystems. A framework for cross-acceptance is being developed at the European level – the Common Safety Method (CSM) – to demonstrate the safety levels of the railway system. (See the related article on page 9.)

The full report (NKS-172) is available at www.nks.org/en/publications/.

[email protected]

Comparing Risk Criteria in Safety-Critical Industries

Focus on R&D

Scope (simplified) of risk criteria in the three industries

Photo: Leif Johnny Olestad


Scandpower has further developed its methods for risk assessment of riser operations on DP rigs in recent projects for StatoilHydro, enhancing its risk model with the use of RiskSpectrum® software.

Over the past two years Scandpower has performed quantitative risk assessments of riser operations for StatoilHydro on two DP rigs – Stena Don and Aker Spitsbergen. DP rigs automatically maintain their position exclusively by means of thruster force. Riser operations involve standard marine drilling risers, high-pressure completion/work-over risers, and TTRD (Through Tubing Rotary Drilling) riser systems.

Primary focus was placed on the blowout risk caused by DP failure (position loss) and failure of Emergency Quick Disconnection (EQD). The risk assessments identified and evaluated various equipment failures and operational errors that could lead to DP failure and position loss, as well as analyzed the risk of blowout.

Scandpower developed the frequency model using state-of-the-art RiskSpectrum® software. The frequencies of position loss, i.e. drive-off and drift-off, were quantified by advanced fault tree models and a total of over 200 basic failure events were considered. Event tree models were developed to model drive-off/drift-off, loss of double-well barriers and blowout scenarios. Most of the nodes of the event tree were linked to fault trees to provide the relevant nodal probabilities. RiskSpectrum made it easy to couple event trees and fault trees and identify critical risk-related items.

As a result, Scandpower was able to determine the blowout frequency due to DP failure given a yearly riser operational activity level and evaluate the consequences of blowout (due to both DP failure and historical reasons) in terms of the impairment of the rig’s main safety functions.

Scandpower’s comprehensive risk model is also well-suited for performing sensitivity studies of the input variables. For example, main factors that may influence blowout risk during riser operations on DP rigs – water depths, DP system and operation, EQD activation, well activity level and weakest point in the riser/well system – were all checked in the projects for StatoilHydro.

Several hardware components for blowout risk reduction options were investigated as well, including the automatic EQD, safe disconnect system (SDS), weak link/safety joint in the riser system, and riser monitoring system. The functionality of these systems was clarified and their risk-reduction effects quantified or qualitatively evaluated. This type of information may provide useful decision-making support generic to all DP units performing riser operations in the North Sea. Generic improvements to Well Specific Operating Guidelines (WSOG) and operational limits were also proposed in the studies.

[email protected]

Risk Assessment of Riser Operations on DP Rigs

Phot

o: N

.N. /

Sta

toilH

ydro

According to Bjørn Abrahamsen, Specialist Marine Operations, StatoilHydro, “The project has provided valuable insight into operational issues of drilling and intervention from DP units and a much-needed update of the risk analyses with relevant scenarios. As new drilling equipment and operational procedures are introduced, new failure modes and risks are often introduced with them. It is essential to update existing risk analyses to reflect these changes.”

“Unfortunately, sometimes risk analysts do not have the proper competence or are not up to date with regard to the systems and operations they are analyzing. This was absolutely not the case for Dr. Chen and his team. They have shown impressive system knowledge, and they have obtained a detailed understanding of the equipment and complexity of the operations within areas that are new to them as a basis for carrying out the analyses.”

Bjørn Abrahamsen, Specialist, Marine Operations, StatoilHydro.

Stena Don by the Faroe Islands.


The software development group at Relcon Scandpower’s Stockholm office is joining forces with Scandpower’s most senior risk analysis specialists to develop a specialized module for RiskSpectrum® PSA to meet the needs of offshore QRA (Quantitative Risk Analysis).

This module will allow Scandpower’s advanced in-house tools for leak frequency calculation, leak duration calculation, and fire and explosion calculation to be directly linked to RiskSpectrum – the company’s state-of-the art fault tree and event tree software. Furthermore, the new module will enable RiskSpectrum software to generate analysis results in formats that are widely known throughout the oil and gas industry and comply with industry standards for risk acceptance criteria.

By using RiskSpectrum software to perform offshore QRAs Scandpower’s clients will not only enhance quality assurance and efficiency with regard to calculations, they will also be able to add on tools such as RiskSpectrum RiskWatcher. This in turn will provide them with numerous opportunities to utilize the results of the QRAs in their day-to-day operations.

Look for updates on these developments in Scandpower Risk Management News and RiskSpectrum Magazine.

[email protected]

RiskSpectrum PSA includes a full set of functions for fault tree and event tree analysis and integration of the two methods.

RiskSpectrum FTA is a very advanced product for fault tree analysis. It is the right choice for anyone who needs powerful fault tree software, but does not need the full-scope PSA features offered by RiskSpectrum PSA.

RiskSpectrum RiskWatcher is used for monitoring online risk, simulating possible scenarios and planning maintance, taking into account the effects on risk. It is optimized to work with PSA models created using RiskSpectrum PSA

RiskSpectrum FMEA is software for Failure Mode and Effect Analysis. It is used for analysing, documenting and quality assuring the input to fault tree models.

RiskSpectrum Doc is software for managing documentation related to risk and reliability analyses created using RiskSpectrum FTA and PSA. It is designed for managing FTA and PSA documentation already in place, but can also replace an existing documentation system.

RiskSpectrum Analysis Tools (RSAT) is a fault tree and event tree solution engine and is included in RiskSpectrum PSA, FTA and RiskWatcher packages.

RiskSpectrum MCS Editor is a separate 32-bit application used for editing Minimal Cutsets (MCS) generated using RSAT.

See also www.riskspectrum.com

RiskSpectrum® Goes Offshore

Retur: Scandpower AS P.O.Box 3, NO-2027 Kjeller

Any time - Anywhere - Under all conditions - Unconditionally

Scandpower ASBergen, Norway [email protected]: +47 55 30 05 55

Relcon Scandpower ABStockholm, Sweden [email protected] Tel: +46 (0)8 445 21 00

Scandpower Risk Management Inc.Houston, TX, USA [email protected]: +1 713 654 1900

Stavanger, Norway [email protected] Tel: +47 51 91 71 70

Gothenburg, Sweden [email protected] Tel: +46 (0)31 335 03 30

Richland, WA, [email protected] Tel: +1 509 946 4334

Trondheim, Norway [email protected] Tel: +47 73 54 63 60

Malmö, Sweden [email protected] Tel: +46 (0)40 93 76 45

Scandpower Risk Management China Inc.Beijing, P.R. [email protected] Tel: +86 10 6467 2860

Sandvika, Norway [email protected] Tel: +47 92 24 71 00

Scandpower Risk Management Dubai, [email protected]: +97 14 426 4855

www.scandpower.com www.riskspectrum.com

Scandpower AS(Headquarters)

P.O. Box 3NO-2027 Kjeller Norway

[email protected] Tel: +47 64 84 44 00

Phot

o: V

igle

ik S

exe

risk management news - riskspectrum - scandpower management news/risk...risk management news 2-2009...

Documents