SIL level issue
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The PID drawings indicate that the SIL level is 2; however, the third-party classification report and the verification calculation both indicate SIL1. Nevertheless, the RRF verification meets the requirements. Is there any problem with this?
If the SIL level required by the PID drawings is 2, but the third-party reports and calculations indicate SIL1, this may be a problem. It is necessary to reevaluate the system design and security features to meet the SIL2 requirements, or communicate with the design team to determine whether the requirements can be adjusted to SIL1. If the RRF meets the requirements, it indicates that the safety performance is satisfactory; however, it is still necessary to ensure that the SIL level complies with the initial design specifications. .
It makes no sense to indicate the SIL level on PID drawings
It means it’s like adding extra details that aren’t necessary, right? Actually, I think it’s possible that they have a misunderstanding of SIL2, which is why they deliberately indicated SIL2 in the PID documentation
I’ve never seen SIL on a PID diagram
Yes, many people are not familiar with the SIL level – it is unclear whether it refers to the SIL level of an individual control valve or that of the entire SIF. As a result, it is possible that the PID settings only specify the SIL requirement for the instrument itself
First, you need to understand what determines the SIL level of an SIF
Your supervisor won’t allow setting the SIL level to 2
For the control of valves and instruments shown in the drawings, isn’t it true that first the SIL level is determined, and then interlocks and controls are set based on that SIL level?
Generally, the SIL level should not be indicated on PID diagrams; moreover, if the levels are inconsistent, it is recommended to consult with the designers to determine a suitable solution