May 2008

Safety system trials begin

The Fieldbus Foundation's (FF) Foundation for Safety Instrumented Functions (SIF) demonstration project will launch this year at multiple locations around the world, reported ARC Advisory Forum.

Field demonstrations will take place at Shell Global Solutions in Amsterdam, Saudi Aramco in Dhahran, BP in Germany, and Chevron in California.

The project will include development of SIF best practices and guidelines and training and interoperability test tools for manufacturers and end users.

The companies participating in the demonstration working group include: ABB, BIFFI, BP, Chevron, Dresser-Masoneilan, Emerson Process Management, Endress+Hauser, Fieldbus Diagnostics, HIMA, Honeywell, Invensys, Magnetrol, Metso Automation, Moore Industries, MTL, Pepperl+Fuchs, Risknowlogy, Saudi Aramco, Siemens, Shell Global Solutions, Smar, Softing, TopWorx, TÜV Rheinland, TÜV SÜD, Westlock Controls, and Yokogawa.

In 2006, FF announced TÜV had granted Protocol Type Approval for the Fieldbus Foundation Safety Instrumented Systems (SIS) specifications.

The specifications outlined by the FF comply with the IEC 61508 standard for functional safety of electrical/electronic/programmable electronic safety-related systems requirements up to, and including, Safety Integrity Level 3 (SIL 3).

TÜV Protocol Type Approval extends Foundation fieldbus technology to provide a comprehensive solution for Safety Instrumented Systems in a wide range of industrial plant applications.

The specifications enable suppliers to build FF devices in compliance with IEC 61508. TÜV will certify these devices are suitable for use in safety-instrumented systems.

End users will be able to choose devices meeting the requirements of IEC 61511 (functional safety: safety instrumented systems for the process industry sector) from multiple suppliers, instead of being restricted to devices designed specifically for a proprietary safety system platform.

Over 90% of the causes for failure are due to the failure of field devices. Today, a safety system should address overall safety needs by checking the health of the I/O, field devices, and valves.


The system should also incorporate components, such as sensor validation, environmental condition monitoring for conditions that can cause sensor degradation, and impulse line blockage monitoring.

Common cause failures of electronic components are frequently due to environmental conditions. Many electronic device failures are due to elevated humidity and temperature, which need to close monitoring.

Sensor calibration is also becoming an integral part of safety systems. Foundation fieldbus technology allows for remote monitoring, diagnostics, and validation.

The Foundation fieldbus SIS concept provides a common platform for SIS and process automation where the automation system and the safety system share the same control network and are able to use common visualization, engineering, and asset management tools, while the logic executes separately for each system.

Sharing a common platform reduces installation costs, eliminates the cost of custom integration, and provides a unified view of control and asset management that encompasses the SIS and the basic process control system, ARC reported.