Guideline 070 in the Petroleum Industry
This summer (June 2018) brought the long-awaited formal release of Rev. 3 of the widely used “NOG 070” guideline. The new revision includes both minor, but also some significant additions and changes to the standard, see below.
Are you interested in knowing more on what these changes mean for you and your projects? Feel free to contact us to schedule a meeting where we can discuss the new Rev. 3 of the guideline and what practical implications the updated guideline has for functional safety in the Norwegian petroleum sector.
Safetec also plans to run a training course this autumn on practical application of SIL in the petroleum industry. The training will also discuss the changes in new revision of the guideline 070. If you are interested in knowing more, you may provide your contact details here. We shall contact you as soon as we have more information regarding dates etc.
Guideline 070 is widely used on the Norwegian Continental Shelf as guidance to operators when applying the IEC 61508/61511 standards, and especially to establish safety integrity level (SIL) requirements for the most common safety instrumented functions (SIFs). This guideline simplifies the application of IEC 61508/61511 standards in the Norwegian petroleum sector.
- Increased focus on IEC 61511
IEC 61511 is a process industry sector specific standard under the generic/umbrella IEC 61508 standard. As such, IEC 61511 is a simplification of the detailed guidance in IEC 61508, and is often denoted as the standard for the end users and integrators (e.g. engineering companies), whereas IEC 61508 needs to be applied by developers of safety instrumented components and logic solvers. This was therefore an expected and well welcomed change to NOG 070.
- Barrier management
The overarching concept of barrier management is introduced in Rev. 3. The PSA’s memorandum on barrier management is introduced, and most importantly, management of functional safety with risk reduction from SIS/SIF is defined as a subset of barrier management.
- Revised minimum SIL requirements
Based on operational experience some of the existing SIL requirements and some new SIL requirements are also added for certain functions.
- Subsea safety instrumented functions (SIFs)
Subsea SIFs are broken down into sub-functions each with their own SIL requirements, and supporting the common primary and secondary barrier terms. This makes understanding and documenting SIL compliance easier, for both designers, system integrators and operators.
- SIS follow-up in operation
This section is more or less completely new in Rev. 3. This new section, with an extended guideline in an appendix, is an attempt to standardize and streamline industry practice on how to best follow-up SIL-in-operation. This section is recommended reading for operators to verify that they have necessary work processes and activities for ensuring adequate focus on SIL-in-operation.
- Architectural requirements (hardware fault tolerance, HFT)
The new and simplified approach introduced in the 2016 update of IEC 61511 is included, where Table 8.4 is included in the guideline (copy of Table 6 in IEC 61511-1) specifying the minimum HFT requirements. Note here that a corrigendum to IEC 61511-1 is published, with a corrected Table 6, and that Table 8.4 in the guideline copies the erroneous table. The IEC 61511-1 corrigendum can be downloaded from this website.
- Other changes
Other significant changes include better clarification of the proven-in-use and prior-use concepts, additional guidance on SIL requirements for overpressure protection of vessels with multiple inlets, new methodology for documenting BOP functions related to well barriers, better and more illustrative examples of SAR, SIL compliance and FSMP reports.
You may access the new revision of the standard here.
Ragnar Aarø, Chief Adviser
Tel: +47 934 83 940