Starting next Friday, we'll review a US Chemical Safety Board incident reconstruction together and look at it from a functional safety point of view. For each incident we'll work through: ➡️ What the hazard was and what should have prevented it ➡️ Where the SIS, alarms or other safeguards failed ➡️ Where in the safety lifecycle the failure started ➡️ Whether it could happen on your project After each session I'll post a short summary of the lessons from experience, so we build up a library over time. First session: 📅 Friday 2nd October ⏰ 10:00 UK 📍 Link in the calendar Comment below if you're wanting to attend. I’ll put a link to the case beforehand

Good morning Everyone, For valve SIL calculations, do we need to include the failure rates of all valve components, such as the solenoid, actuator, and valve body? Should the actuator and valve body also be included?

Good day everyone, I have few questions on SIL Calculation. I have a PILZ controller in SIF and try to make some calculation by hand. Controller has DI and DO with CPU. 1. If I would like to calculate PFDavg for Controller then I should combine DI, DO and CPU PFD avarage, correct? (No redundancy at DIs and DOs) For ex, PFD input, single + PFD output, single+ PFD CPU = 2,20 x 10^-4 + 1,30 x 10^-5 + 6,20 x 10^-5 (See please certificate) 2. As you see the certificate shows only PFD but not λ DU. Can I calculate my λDU from PFD as referencing the formula below? PFDavg = (λDU * T)/2 . Actually, the certificate does not say what T has been taken into account on PFD calculation as well, but I am going to take it as 1 year. 3. CPU Part: 773103 ( PNOZ m1p ETH) ; Certificate Link: https://www.pilz.com/download/open/PNOZmulti_TUEV-Sued_BM_M6A-020132-0284-R01_R4_4_valid_2030-Jun-24_1002803-BM-34.pdf Thank you!