Safety integrity level (SIL) is defined as a relative level of risk-reduction provided by a safety function, or to specify a target level of risk reduction. In simple terms, SIL is a measurement of performance required for a safety instrumented function (SIF).

SIL is calculated for SIF’s using specific formulas, taking in account different factors like λdu (rate of dangerous undetected failures), test interval, voting, SFF (Safe Failure Fraction), etc.

We are the group of SAS engineers and software developers. During work with different projects we have seen different approaches for SIL calculations. In some projects SIL levels are calculated manually, some companies design spreadsheets to minimally automate calculations. It is obvious, that SAS sector needs software to automate SIL calculations and maintenance, thus reducing engineering time, cost and probability of mistakes. We have started SIL ToolBox project to fulfill this demand. The goal of SIL Toolbox project is to develop software for design and assessment of Safety Automation Systems, providing integrated working environments for companies or individual engineers.

Project is in development phase and public access is intended for testing and evaluating purposes. Any proposals on usability and functionality of software are highly desired. If you are interested in engineering automation software and can give us any feedback, it would be appreciated. Please send feedbacks to and join our groups LinkedIn Facebook

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