What are the most common mistakes made during HAZOP studies for offshore operations?

Preparation always plays critical role for any risk assessment (e.g. HAZOP) since it will define to which direction the study will go. It could start from defining comprehensive Term of Reference (ToR, or "Charter" for some organization) to set study boundaries and expectation. The ToR will also set a rule on who should be the leader, scribe, and team members (and back up members), agree on guidewords relevant to the studied system, and other relevant requirement to ensure consistent approach is to be maintained during the study. The ToR could even mention "meeting rule" to ensure focus & discipline throughout the sessions.

Based on my experience running and participating in offshore HAZOPS includes absence of TOR, inexperience facilitator and members, lack of relevant document including unupdated as built drawing and organization of HAZOPS session. ....hery sultoni....

I find HAZOPs rather painful when I find the Node Mark-Ups are incomplete, not linking P&ID to P&ID and not clearly defined battery limits. Where does it stop and start? A system should be fairly easy to define, colour code, label and schedule out, often lost in poor P&ID's by Engineering impacting poor HAZOP Node Identification. A clear description of the Node by the Chair is required so members have a complete handle on the process under review.

3. Inadequate Team member: need to ensure the team composition fulfilled: Qualified Facilitator, Effective Scriber, Process Engineer, Design Engineer, Operation Reps, HES Reps, other discipline Engineer as required, depend on case - may require vendor, inspector, maintenance, fire protection expert. 4. Inadequate Documentation, normally for new project, all drawings required are available. The common issue is to ensure the latest drawing bring to the table for discussion. For revalidation, List of MOC and the latest drawing are very important for the quality of study. Also for revalidation, O&M Reps is key team member for the quality of study since they are the most knowledgeable regarding with new risk/unidentified of operated facility.

In my experience, facilitator plays a central role in HAZOP. A good facilitator brings the most out of the team and ensure a high quality discussion. More often than not, Companies don’t invest in developing high quality facilitators in the organization and/or reluctant in hiring a competent external facilitator to lead the HAZOP studies due to the cost related to the investment or hire. As a result, the quality of the HAZOP is compromised. Therefore, it is important to invest in having a highly competent facilitator

Doing the HAZOP via Zoom or MS teams as the limits the interaction between the participants. Also it is veri difficult to give proper attention to P&IDs and HAZOP sheets using screens.

A well-built team is crucial in HAZOP. The result of HAZOP is really dependent on the competency and completeness of the participants. My experience shows that for the same facility, the result of the HAZOP study will be different if the team members are different. In my case, the studies were HAZOP baseline and HAZOP revalidation of the same facility. It should yield a similar result, however, the actual result was very different.

Nearly every P&ID will have Alarms, Interlock, PSD &/or ESD Detail flags with references to C&E's, Logic &/or Control Narratives. If the documentation is not immediately available, the series of questions being "What is the Alarm Value", "What is the Control Action", "What is the effect of this Interlock or Trip" etc cannot be answered. The HAZOP quickly becomes rather pointless.

Based on my current Ph.D. dissertation, three common quality parameters are: completeness, reliability, and validity. Completeness. Many HAZOP study have this lack of completeness problems. In one of a HAZOP study, I found that HAZOP only discussing 57% of all PSVs (as safeguard) which are actually written in P&ID. Reliability. Often, if HAZOP was conducted by different teams, it resulted in (completely) different discussions (shown on worksheet). Some of the causes are lack of obedience to Terms of Reference (TOR), no TOR, no reviewing process. Validity. Validity of HAZOP may resulted by lack of thouroughness discussions, epistemic and aleatory problem. This can also be aggravated by lack of operational experience of the facilitator

Other common pitfall to avoid: 1. Missing the risk communication step; Once Major Accident Hazard is identified, follow this up with risk communication to relevant personnel. Use/update BowTie if your organization use it. 2. Stopping only at HAZOP and missing other technical safety aspects. HAZOP is good for analyzing process deviation. Offshore environment hazards are beyond process hazard. Marine, aviation, the remoteness to the central operations hub should also be assessed. Use a more generic method like what-if and HAZID to supplement your HAZOP. 3. Creeping change are often overlooked. Some changes are subtle and occurs over time, such as reservoir souring, change in Gas Oil Ratio - these changes may impact Safe Operating Limit.