How do you conduct a HAZOP study for pipeline systems?

Important to understand design intent of the system under consideration. Following documents must be read through: 1. Design Basis 2. HMB 3. Operating Philosophy 4. Operating Modes 5. Startup considerations 6. P&ID Walk through

First of all, It's important you understand the design intent of the system you are considering. This will help you in deriving deviations in your study. The Piping and Instrumentation Diagram is the most important document for a Hazop study, have it handy. Mark out your node. What are the process variables for which you'd like to carry out your study? Typically, it'll be Pressure, Temperature, Flow, Level and maybe concentration. Apply guide words (No, More, Other than, High, Low) to these Process variables to obtain deviations. For example No flow. What could cause it? what are the consequences? Study the consequences and give recommendations.

Nodes should be marked up on piping and instrumentation diagrams (P&IDs) and shared with HAZOP attendees, prior to the scheduled date for starting the HAZOP Workshop. This will save time and make the workshop more efficient. It is recommended to use a proprietary HAZOP software to record HAZOP discussions. This should be pre-populated with information such as nodes, process conditions, P&ID numbers prior to the HAZOP. Note that any pre-population exercise done prior to the workshop should be discussed at the start of the workshop for agreement by all attendees.

Walking the P&IDs prior to the HAZOP to verify accuracy is very important, since the instrumentation is often cited as a safeguard. Doing this with a process operator can also be valuable, as they will tell you which controls no longer function as intended.

Hi good morning, I would like to add below 02 points: 1. It is important to use company Risk Matrix for adequate rating of each recommendation like severity and likelihood etc. 2. HAZOP close out is very important so Close out sheets for each recommendation are very important. Regards

Recommendations should be clearly documented with clear wording that what is required from the assigned party. Choice of words are important, e.g. provide, review, study should be chosen carefully and to be agreed by all involved parties.

During the HAZOP workshop, recommendations should be assigned to only attendees of the HAZOP who are often identified on the HAZOP worksheet by the discipline or department they represent (note: names are not necessary as personnel may change). There should also be a clear distinction between a recommendation and a “parked item”. A parked item can usually be resolved quickly and before the end of the HAZOP because the information is available in the organisation but not available to the HAZOP team at that point in time. During the HAZOP, the facilitator would make a note of parked items on a flip chart in the meeting room or in Microsoft Notes App if it is a Virtual HAZOP. Parked items are crossed out once resolved.

Where the HAZOP is carried out for a project, all the recommendations should be closed out /resolved by the end of that project and the HAZOP report should be updated to include recommendation close-out sheets or a spreadsheet (including associated evidence). The report should then be re-issued as a HAZOP Close-out Report, and reviewed, approved and communicated to all relevant stakeholders and authorities. The HAZOP Report is a good reference document and source of information for conducting a Layer of Protection Analysis (LOPA) or Safety Integrity Level (SIL) Assessment.

Actions Register shall be created or generated when all Systems have been Completed in the HAZOP, Actions closure follow up shall be done and ensure all Actions are closed by end of the design. Evidence sheets for actions closure to validated by the Technical lead Engineers.