Functional safety - Instrumented safety
A Safety Instrumented Function (SIF) forms an independent protection layer. The required SIL level is determined on the basis of the HAZOP and LOPA analysis.
SIF/SIL loop design
We offer comprehensive services for designing and verifying Safety Instrumented Functions (SIF) or SIL loops. Our aim is to guarantee the safety function and the intended risk reduction through clear and precise definitions of the SIF(s) and all variables that may affect them.
In the Safety Requirements Specification (SRS) phase, we describe the requirements and operation of all SIFs. This process results in the delivery of the SRS with annexes such as an Environmental Checklist, a Cause & Effect Matrix and a concept SIL loop diagram.
We then focus on the design and verification of the SIS. In this phase, we specify all components, carry out electrical and software engineering, and verify the SIL. We also draw up a test protocol for periodic tests and a SIL validation report for the Site Acceptance Test (SAT). In addition, we can program the logic of the SIL loop or provide support with this.
SIL verification
A correctly designed Safety Instrumented Function (SIF) is only reliable if it can be objectively demonstrated that the required Safety Integrity Level (SIL) is actually achieved. Prohead Engineering has the expertise and tools to carry out this verification accurately and efficiently.
We test the design of the safety loop against standards such as IEC 61508 and IEC 61511, and assess, among other things, the Probability of Failure on Demand (PFD), system architecture and component reliability. With our knowledge of automation and process safety, we help think through alternatives if the SIL requirement is not met.
The verification is carried out with recognised software and according to the state of the art, which produces transparent and reproducible results. This is how we ensure that your safety functions also meet all requirements in practice.
Functional Safety Assessment (FSA)
Our colleagues are TÜV- and/or Exida-certified experts with extensive experience in carrying out FSAs for both internal and external projects. These assessments are essential to guarantee that your safety systems function reliably and comply with standards such as IEC 61508 and IEC 61511.
We provide support for FSA 1 up to and including FSA 5, ranging from the assessment of the SRS and PHA, through checking the design and installation, to evaluations during operation and in the event of modification or end of life.
Our structured approach ensures that all phases of the Safety Lifecycle are critically reviewed, so that your safety functions remain optimal and demonstrably compliant.