Can a DCS system be used for SIL assessment?
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Is the SIL assessment based on SIS systems? Can DCS systems be used for SIL assessment? Why?
Is the SIL assessment based on SIS or DCS? It might be two different things. Refer to http://bbs.hcbbs.com/thread-874440-1-1.html
DCS can perform SIL assessments; the SIS system is independent of the DCS system, and it operates in cases where the DCS fails, offering a higher safety level than the DCS； But this does not mean that DCS is not involved in safety control. DCS still needs to handle emergencies, which requires a SIL assessment. Moreover, both the software and hardware in DCS systems can be selected with SIL certification; of course, that is quite expensive.
To determine whether an SIL assessment is necessary, you first need to understand the definition of SIL (Safety Integrity Level). According to the requirements of IEC61508, in cases of special circumstances or issues related to safety conditions, not only DCS systems but also field smart meters can apply for SIL certification. Having SIL certification is an indication of a product’s safety level, and products with such certification tend to have higher prices. As for what safety level the facility needs to achieve, this will also be mentioned in the safety pre-assessment report. Relevant domestic documents are also set to be issued soon.