Example demonstration and sharing of Safety Integrity Assessment (SIL verification)

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This post was last edited by live859 on 2019-11-8 at 09:26. It mainly introduces the functional features and operation instructions of the SIL verification software, so that everyone can understand the process of SIL verification. By watching this video, you can learn how the SIL verification software is designed, and which parameters are closely related to the SIL level. Factors such as system operation time, system testing time, and voting modes all affect the probability of dangerous failures in the SIL circuit. Additionally, if you need SIL verification software, you can use some of the methods discussed in this video when selecting such software to ensure the completeness of its functions and the accuracy of the verification data (just one TVU certificate is required). SIL verification is a rigorous process; the Markov algorithm is complex and precise, and software can also be used to determine whether the data related to the SIL certification of certain devices is accurate. The software used in the video is the SIL verification software independently developed by Hangzhou Haopeng Technology, while the failure data are those from TVU certificates to demonstrate the verification process. During the verification process, check whether the PFDavg (average failure probability under hazard) calculated by the software is consistent with the PFDavg value provided in the tuv certificate. The functions of this software and its verification results have been compared with those of the well-known SIL verification software exSILentia earlier (for details, please refer to…). Haopeng Technology assumes responsibility for the SIL verification algorithms. The TUV certificates for the equipment used in the video are shown in the figure below: For the radar level gauge, the SIL certificate indicates that the value of DD for undetected critical failures is 2154, while the value for detected critical failures is 158. The component type selected is Type B, the testing period is 5 a, that is, 60 months, and the testing coverage ranges from 93% to 98%; the intermediate value of 96% is used in the CTI testing coverage calculation. The average failure probability under hazardous conditions PFD for the 1oo1 sensor is 3.82E-3. The average misstop rate of MTTFS is calculated based on safety failure data, but no such data is available in the SIL certificate. If the certificate does not contain information on SDs that have been detected as safety failures and SUs that are not considered dangerous, it is impossible to calculate MTTFS. The applicant shows the Safety Integrity Level SIL rating of Zhejiang Lianda Valves; if HFT=0, then it is SIL2, indicating that with a hardware margin of 0, the valve reaches SIL2 level. If the hardware margin is 1, then the valve can achieve SIL3 level. Content on the certificate on page two: The certificate shows the number of dangerous failures; in the case where no dangerous failures are detected, the values of DU under the normally open and normally closed conditions are 2.78E-7 and 3.69E-7 respectively. The requirements for normal-open and normal-closed states in safety failure scenarios are 2.78E-7 and 1.82E-7 respectively. The test period is 12 months, the average MTTR for recovery is 24 hours, and the Bate value is 10%. Li Qiang, Product Manager at Hangzhou Haopeng Technology Co., Ltd., is an Oracle-certified senior database expert who has participated in nearly 100 HAZOP and LOPA analysis projects