SISTEMA is a free Windows program from Germany’s occupational safety research institute that calculates whether a machine’s safety control system meets its reliability target. It is machinery software, built around the machinery standard EN ISO 13849, and it works in high-demand terms rather than the low-demand math a safety instrumented function needs.
For those of us in the process industry its value is narrow. Know it mainly so you can read what a skid vendor hands you.
Deep dive: For how SISTEMA and its B10d libraries fit, and often do not fit, low-demand SIL work, see Where Does the Data Come From? A Guide to Failure Rate Data Sources in Functional Safety.
Key Points
- SISTEMA ships empty. The failure rate data lives in separate files that component manufacturers publish on their own websites, roughly 75 of them, with no central database.
- Those files are plain text in a standard industry format, so the numbers can be pulled out without installing anything. What you get is model-specific dangerous failure rate data for machinery parts — relays, contactors, solenoids, interlocks — and nothing for process instruments.
- Nothing is automatic. SISTEMA never fetches data and never checks for updates, and once a component is copied into a project the link back to its source is gone.
Example
A packaging skid arrives with a machinery reliability rating and a SISTEMA file behind it. Because the software costs nothing, you can open the vendor’s file yourself and check the assumption that drives everything downstream: the operations-per-year figure they used. That number is the vendor’s guess about your plant, not a measured value.
See Also: OREDA, failure rate, B10 testing
Cited Sources
- Institute for Occupational Safety and Health of the German Social Accident Insurance (IFA) — SISTEMA
- EN ISO 13849-1:2023, Safety of machinery — Safety-related parts of control systems