Calculation library
Functional safety calculators
Screening calculators for SIL work under IEC 61508 and IEC 61511. Each one shows its working, the standard it follows, and a link you can share.
SIL, failure rates and architecture
Quantitative SIL bands, failure-rate data and architectural constraints for safety instrumented functions.
SFF / HFT calculator
Architectural SIL from safe failure fraction and hardware fault tolerance (Route 1H, 2H, Table 6).PFD / PFH calculator
PFDavg and PFH for one 1oo1 channel from λDU, proof test and diagnostics.PFD, RRF and SIL calculator
PFDavg ↔ RRF ↔ SIL band, and PFH ↔ SIL for high demand.Proof test interval calculator
Interval for a target PFDavg from λDU and proof test coverage.Diagnostic coverage calculator
DC from λDD and λDU, with the IEC 61508-2 band.Process safety time calculator
SIF response-time budget against the process safety time.FIT to MTBF calculator
FIT, failures per hour or year, MTBF and MTTF, both ways.Chi-square failure rate estimator
Failure rate from field data with a 70 % or 90 % chi-square confidence bound.SILProof
From a screening number to a verified SIL claim
The calculators answer one question each. SILProof keeps a safety function’s risk basis, SRS and three-gate SIL verification on one record, with an issued report.