RAMS group involvement in PDS
The PDS-forum is a key arena for the RAMS group. It gives us a unique environment where we can allign our research with the needs of the industry and the society.
PDS Forum is a co-operation between around 25 members representing oil companies, drilling and well service companies, engineering companies, consultants, vendors and researchers, with a special interest in Safety Instrumented Systems.The RAMS group has been an active member and contributor the PDS forum since the forum was formed 25 years ago. Another active member has been the department of Engineering Cybernetics department at NTNU with Professor Tor Onshus.
Some examples for research projects where the RAMS group has contributed are:
- PDS method and data handbooks. The PDS method and data handbook are are updated on a regular basis. The RAMS group has been involved in all recent updates. The RAMS group has also been a key project partner in developing the PDS Tool which is a computer-based tool for reliability quantification of safety-instrumented systems using the PDS method.
The PDS method is used to quantify the safety unavailability and loss of production for safety instrumented systems (SISs) using analytical formulas. The method has been widely used in the Norwegian petroleum industry, but is also applicable to other business sectors. The PDS method is in line with the main principles advocated in the IEC standards. The PDS data handbook provides data that supports the quantification, and the data are based on various sources, including operational reviews of reported failures at onshore and offshore oil and gas facilities, the OREDA data base, expert judgments, and data provided by manufacturers.To overcome some of the weaknesses in the IEC standards, the PDS method suggests an alternative approach to modelling of common cause failures (that is more sensitive to voting) and how to incorporate systematic failures, a failure category that is contributing to many of the failures reported in operation.
- Common Cause Failures in Safety Instrumented Systems (part of the joint-industry research project "Tools and guidelines for integrated barrier management and reduction of major accident risk in the Petroleum Industry" funded by the Norwegian Research Council and members of the PDS forum 2013-2015).
This research task included review of about 12 000 notifications, where the purpose was to identify common cause failures for SIS related equipment. New estimates of the beta factor for selected equipment are provided, along with checklists that may be used to update beta factor values in light of plant-specific considerations.
- Barriers to prevent and limit acute releases to sea (part of the joint industry project "Development of barriers and indicators to prevent and limit pollutants to sea" funded by the Norwegian Research Council and members of the PDS forum 2010-2012).
This project was motivated by the Deepwater Horizion accident and other well control incidents and accidents that have pointed at the lack of control with the integrity of key well barriers, including those that are based on electrical/electronic/programmable electronic technologies. The project report includes a thorough review of performance requirements and technical requirements associated with drilling and well intervention barriers. In addition. the report proposes a method to analyze the risk under different failure scenarios and suggests suitable indicators for each barrier.
- Reliability Prediction Method for Safety Instrumented Systems - PDS Example collection (part of the joint-industry research project "Development of barriers and indicators to prevent and limit pollutants to sea" funded by the Norwegian Research Council and members of the PDS forum 2010-2012).
This report discusses some of the modelling challenges analysts may face for more complex safety-instrumented systems. A collection of worked examples showing how the PDS method may be applied on some practical cases and problems are also included.
- Use of the PDS Method for Railway Applications (2009)
The project report demonstrates how the PDS method is applied to the analysis of railway signalling systems, and to explain how the PDS method relates to definitions and approaches suggested in EC 61508.
- Guideline for follow-up of Safety Instrumented Systems (SIS) in the operating phase (part of the joint-industry research project "Management and follow-up of SIS integrity" funded by the Norwegian Research Council and members of the PDS forum 2007-2009).
The guidelines describes work processes, activities and methods considered appropriate to ensure that the safety integrity level (SIL) of the safety instrumented systems (SIS) is maintained throughout the operational lifetime of the given installation. The main application area is the oil and gas industry, but the guideline may be relevant also for other industry sectors. This guideline has been widely adopted by the industry, both by the oil companies and the consultancy companies who have developed tools and methods to support the practical implementation. SINTEF has also carried out a high number of operational reviews (where also members of the RAMS group have been involved), where the methods advocated in this guideline has been used as basis.
All reports are available from http://www.sintef.no/projectweb/pds-main-page/pds-research-projects/.
PDS is the Norwegian acronym for "reliability of computer-based safety systems".
PDS Forum is a co-operation between around 25 participants representing oil companies, drilling and well service companies, engineering companies, consultants, vendors and researchers, with a special interest in Safety Instrumented systems. The PDS Forum was initiated in 1995 as a follow-up of the PDS method development projects. The main objective of the PDS Forum is to maintain a professional forum for exchange of experience between vendors and users of control and safety systems. The primary focus is on safety and reliability aspects of such systems. The web page of the forum is found at SINTEF pds. The participants are meeting twice a year for workshops, presentations and technical discussion. The PDS forum has also initiated several joint-industry research projects, which has received financial support from the PDS members and the Norwegian Research Council. The administration of the forum is carried out by SINTEF Safety Research.
PDS method used to quantify the reliability, the safety, and the life cycle cost (LCC) of safety instrumented systems. PDS has been developed through a series of development projects conducted by SINTEF/NTNU in close co-operation with the industry. It is widely used in the Norwegian offshore industry, but is also applicable to other business sectors.