Definition:
A SIL Certificate is an official document issued by a Certification Body (CB) that confirms a product, device, or system has been independently assessed and certified to meet specific Safety Integrity Level (SIL) requirements according to standards such as IEC 61508.
This document is issued by a CB (such as Exida or TUV) and applies to the product line. They are often available on their website. This file will contain the relevant information to perform PFDavg/STR calculations. Note that this is different from the SIL Declaration of Conformity which comes from the manufacturer, often in the box or the document package.
Key Points:
- Issued by independent accredited Certification Bodies (e.g., TÜV Rheinland, Exida).
- Covers assessment of hardware fault tolerance, systematic capability, failure rates, diagnostics, and design processes.
- Specifies the systematic capability (e.g., SC 2 capable).
- Typically based on detailed analysis including FMEDA reports and lifecycle process audits.
- Often available on the manufacturer’s website as a reference for Engineers..
- Would be searchable on the CB’s website.
Example:
E&H makes a SC 2 capable pressure switch. E&H used Exida (the CB) to do the assessment for that line of pressure transmitters. Thus the SIL certificate is a document by Exida. The SIL Declaration of Conformity would be issued for the particular PT in the box by E&H. Maybe by the individual instrument or the lot.
See Also: SIL declaration of conformity, certification body, systematic capability
Cited Source:
- IEC 61508-1:2010, Clause 8.2.
- TUV offers product assessments