Can points that are not present in the LOPA analysis loop be integrated into the SIS system? Are there any relevant regulatory guidelines for this? ? ? ?

SYT10045-2003 Application of Safety Instrumented Systems in Industrial Production Processes. Ask the design institute or the third party conducting the assessment for you.

This post was last edited by J 丶 L Midnight Wanderer on 2020-5-27 at 11:24. Guidelines for the application of LOPA per GBT 32857-2016; Guidelines for the use of LOPA methods per AQT 3054-2015; Functional safety standard for electrical/electronic/programmable electronic safety-related systems per IEC 61508； IEC 61511 – Functional safety standard for safety instrumented systems in the process industry ； SYT10045-2003 Application of Safety Instrumented Systems in Industrial Production Processes.

In industrial practice, after qualitative hazard analyses such as HAZOP and checklists are completed, LOPA is generally applied to those parts of the results that are too complex, too dangerous, or for which SIS requirements have been identified. If the results do not contain any parts that are overly complex, overly dangerous, or require SIS implementation, then the SIL classification is carried out directly; based on this classification, it is determined which points need to be included in the SIS. Thus, points that are not present in the LOPA analysis can be incorporated into the SIS system. The specifications for the upper floors were set well in advance, so I won’t list them.

Sure~ In theory, you can include all the points you consider important in SIS, as adding it provides an additional layer of protection; it’s never too much to enhance security. It should be noted, however, that a small number of points can be added to SIS, but adding a large number of process control points is not feasible. GB50770 5.0.10 explicitly stipulates that the safety instrumented system shall not operate between or in place of the basic process control system. So if you personally think that a certain person is important, you can add them as long as there is a reason for it (we have projects where the entire driving control process is placed within the SIS); but if everything is included, that would pose problems. Anyway, due to the methods used in this HAZOP analysis, different results are obtained each time; there’s no need to get too focused on just one or two aspects. Those elements that must be included in the analysis should definitely be included, while those that aren’t necessary can be considered on a case-by-case basis.

If there are some points that have not been analyzed and are not included in the HAZOP analysis report and LOPA report, can they still be included in the SIS?

Anything used for safety interlocks is acceptable, even if it isn’t mentioned in LOPA. However, the SIS system generally does not participate in normal production control, although it is technically possible to do so. Remember! As long as it is for safety! That will do.

Points that are not included in the LOPA analysis can also be incorporated into the SIS; according to Document No. 320124 116 issued by the General Administration of Work Safety, those related to two key areas and one major hazard must be included in the SIS. There is a prerequisite for entering the SIS: it must meet the requirements of clauses such as 5.0.8/9/10, 6.1.7, and 7.1.3 of GB T50770-2013.

The LOPA report must be included in theory； The provisions on two key points and one major issue must be included ； **Entry is required as stipulated; for example, Jiangsu requires that the liquid level in chlorine storage tanks be at the SIL2 level. In LOPA, those with a PFD of 0.1–1 can be determined according to the client’s requirements

Of course. LOPA is just one method for SIL classification; in China, it is commonly used to determine which systems can be included in a SIS. But besides LOPA, other circuits that you consider important can also be included. But don’t go overboard with it, and don’t use it as a BPCS.