risk scoring at all; it is too poor of a method. And we recommend using quantitative methods (starting with LOPA) only on scenarios that are too complex for the PHA/HAZOP team... to make a judgment on tolerability of risk (i.e., only when they recommend further analysis). Of course, this approach depends on great HAZOPs that are staffed by, and led by, experts... the residual risk is at a local plant/unit. Anyway, that is our data and conclusions from the thousands of such analysis we have led and documented. If you want to find more data, please...

of the CCPS books on LOPA (2001 and 2012), I (and many others) believe we are doing Too Many analysis. A well-structured and well led PHA team does 95% of the risk analysis and 99...Separate Analysis for SIL are NOT Needed; and Overuse of LOPA... About Expertise Training Courses Calendar Instructors Course Registration Private Training Coaching Consulting... Improvement Institute Blog news related to process safety, process reliability, and human reliability / Separate Analysis for SIL are NOT Needed; and Overuse of LOPA Separate Analysis...

% of the risk analysis and 99% of the risk identification. LOPA is only Read More Posted on: July 15, 2012 Posted in: Uncategorized Double-Jeopardy in HAZOP and What-If 0 Double... and Owner companies do not really understand best practices related to risk analysis and independent protection layers (IPLs). This is unfortunate. This lack leads to a lot of wasted... cause-consequence pair, the worst combination, for the order-of-magnitude risk estimate. Other methods, especially Fault Tree, are more appropriate to treat multiple initiating events...

on LOPA (2001 and 2012), I (and many others) believe we are doing Too Many analysis. A well-structured and well led PHA team does 95% of the risk analysis and 99% of the risk... not really understand best practices related to risk analysis and independent protection layers (IPLs). This is unfortunate. This lack leads to a lot of wasted resources. Also..., the worst combination, for the order-of-magnitude risk estimate. Other methods, especially Fault Tree, are more appropriate to treat multiple initiating events. Many times simply summing...

by: Bill Bridges The CCPS book clearly states LOPA uses a single cause-consequence pair, the worst combination, for the order-of-magnitude risk estimate. Other methods, especially... available without the simplifying assumptions of LOPA. But, these other methods are not usually required since HAZOP/What-If will work for risk judgment about 95% of the time... (no quantification required), LOPA will handle the risk determination of most of the remaining scenarios, then the more complex QRA methods may be necessary for a scenario about 1% or 0.1...