Per OSHA and per CCPS, a PHA is the risk analysis for the unit for all modes of operation. CSB has been really hitting hard lately as well. (See the Bayer CropSciences report for a good example.) The most critical part of that analysis is the portion for startup, shutdown, and online maintenance, since 80% [...]
Our data differs. We have performed more than 11,000 unit-sized PHA/HAZOPs over the past 24 years; 1,000 of these have been new designs (projects, as you have focused on); the rest have been re-do of existing plant PHAs (because the project PHA/HAZOPs were so deficient). If you have a good engineering team then the team [...]
Our data on 11,000+ unit sized hazard reviews to date (using HAZOP, What-if, and variations) show that using a risk matrix detracts from brainstorming and does not improve the risk judgment of a multiple discipline team of process and operations with good to excellent expertise. If you don't have such a team, then you will [...]
If you used LOPA to determine if you need a SIF and to identify what SIL is required (if any), then you cannot share or partially share a final element. So, if the BPCS control loop is the cause (initiating event) and that loop uses the final element in question, then that same final element [...]
We don't recommend using a risk matrix during PHAs/HAZOPs. matrices are good tools to teach risk concepts, but in a well led PHA/HAZOP they reduce quality more than they increase quality. To see much more details, download and read this free paper: http://www.process-improvement-institute.com/wp-content/uploads/2026/04/Optimizing-PHA-HAZOP-while-maximizing-brainstorming-2024-R5-with-award-image.pdf We use a risk matrix and a risk tolerance criteria only when [...]
