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OREDA

Definition:
OREDA is an industry-maintained reliability database owned and governed by the OREDA Joint Industry Project (JIP), a consortium of companies primarily from the offshore oil and gas sector. It provides failure rate and failure mode data for equipment used mainly in offshore applications. OREDA is referenced in reliability engineering, maintenance planning, and functional safety activities—especially when estimating failure rates for mechanical and process equipment where manufacturer data is limited or inconsistent.

Access to OREDA data depends on participation level. Member companies contribute field failure data and receive full access to the detailed database, handbooks, and analytical tools. Non-members can access selected publications and datasets, typically at a higher cost and with reduced detail.

In the context of IEC 61511 work, OREDA is used as a source of generic mechanical failure rate data, applied with appropriate engineering judgment.

Importantly, OREDA does not replace vendor-specific FMEDA data for sensors, logic solvers, or certified final elements. Where high-quality, device-specific FMEDA data exists, that data is generally preferred for SIL verification.

From a certification and justification perspective, OREDA supports prior use and analytical approaches (e.g., Route 2H) by providing credible, industry-wide failure rate benchmarks. It does not, by itself, satisfy proven in use (PIU) (Route 2S), which requires device-specific operational history, but it may be used alongside that data as part of a broader justification.

Key Points:

  • OREDA is a structured reliability database developed and maintained by the joint group of companies, based on real field failure data.
  • OREDA has failure rates, failure modes, and distributions
  • Typically used for prior use arguments, can support credibility to a PIU argument
  • How it’s used in functional safety:
    • Used when vendor FMEDA data is unavailable or unsuitable
    • As an input for failure rate assumptions in SIL verification
    • Often applied to final elements and mechanical components
  • Important limitations:
    • Data is not device-specific; it is based on equipment classes, sub-categories, and service conditions, not model numbers.
    • Collected primarily from offshore environments—may not represent other services
    • Requires careful justification and conservatism when applied to IEC 61511 SIS calculations
  • OREDA is used by different entities in the FuSa lifecycle
    • Used by facility engineers: To support prior use justifications and failure rate assumptions in SIL verification when device-specific data is unavailable
    • Used by manufacturers and certification bodies: As an input to FMEDA and failure rate modeling to support SIL capability justification (e.g., analytical approaches such as Route 2H)
  • As more SIL-certified components become available, reliance on OREDA has decreased and is expected to continue decreasing for many SIS applications, in the opinion of many practitioners, though it remains relevant where device-specific data is unavailable or not representative.

Example:
Example 1 – When OREDA is Useful
A SIL 2 SIF includes a pneumatically actuated final element.

  • The valve the facility desires is not SIL certified
  • The engineer selects an OREDA failure rate for a comparable valve type and service class.
  • Conservative assumptions are applied (e.g., worst-case failure mode selection).
  • The selected OREDA data source, edition, and rationale are documented in the SIL calculation
  • This is a prior use (generic data) approach consistent IEC 61511-1 §11.5.3; certification body involvement is not required to justify the device’s use in a SIF.

Example 2 – When OREDA Is Not Necessary
A SIL 2 pressure protection SIF uses a pressure transmitter and an ON/OFF valve, both are SIL certified. The SIL Certificate (with FMEDA data) has all the information needed. OREDA is unnecessary. Perhaps it was used as some justification by the Certification Body, but in the end that is not relevant to the facility FuSa engineer.

Example 3 – Manufacturer + CB using OREDA
A manufacturer is seeking SIL certification for a shutdown valve but lacks sufficient device-specific failure data. They use OREDA failure rates for comparable valve types as inputs to their FMEDA. The certification body reviews the data selection, assumptions, and applicability to ensure the failure rate justification is appropriate and conservative.

See Also: failure rate, RAM, proven in use, prior use

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Part Of: bodies and organizations category