Doing a HAZOP Study? The three things you must consider

What is a HAZOP Study?

HAZOP is an acronym for Hazard and Operability Study. It is one of the most popular hazard and risk assessment techniques used in industry and especially so the process industry (think Oil & Gas production, Petroleum refining, Chemical manufacturing, bulk pharmaceuticals manufacturing, Food & Beverage, Fossil Fuel power generation and so on), It is also very popular in industries like Mining and Metals processing, Pulp and Paper, Water & wastewater.  The process of carrying out the Risk Assessment using this method is known as a HAZOP Study.

Although many people claim to have been trained and/or knowledgeable and experienced in carrying this out, many of them do not consider these three things in their study. If you are new to HAZOP, then you can see the video below to get a fair idea of what it does. Once you complete watching it, you can read on below.

So most people who do this Hazard and Operabililty Study go through the motions of breaking down the process into nodes, using guide words to generate and analyze deviations and think of what mitigations can help them take care of the deviations. However, there is more to conducting a HAZOP then just carrying out this exercise.

Let us now see what are the three important things that often get missed out.

1. Human Factors HAZOP

Most people, even some HAZOP Professionals do not include human factors into their analysis. However many process plant operations are carried out by humans and they are prone to making errors and mistakes. If you do not analyze these, then your HAZOP Study is actually not complete.

If you take the Abhisam HAZOP Certification course, you can learn how to include human factors in your analysis. You can use the human factor guide words in the course to analyze the deviations that are possible due to human actions.

Read more here on Human Factors analysis.

2. HAZOP Management

This is an often underrated factor in a successful HAZOP Study. If the study is not managed well, then you end up with a really bad one. A bad study is sometimes worse than not having carried out any study at all! This is because it gives the plant or facility owners a false sense of security, that a HAZOP has been done and now everything is safe and hunky dory. All is well!

This is dangerous because if many of the deviations and possibilities have not been considered at all, then they will not be taken care of and there could be an undesirable incident. The asset owner or the plant’s management will likely come to know of the HAZOP being badly done, only after it is too late and an incident occurs.

Here is where a good HAZOP Leader can make all the difference in the team’s output. The HAZOP Leader has to actively do many things to ensure that the study goes well.  The Abhisam HAZOP Leader course covers this very well and is a great way for HAZOP Professionals to learn how to manage the study professionally.


CHAZOP is an acronym that stands for Computer HAZOP or Control HAZOP. This technique is used to analyze the Computerized Control System that the plant uses, in order to know if it can be relied upon when something goes wrong. If you have sat through many HAZOP Studies, you will notice that most of the mitigations refer to having alarms sound in the control system, or interlocks tripping something.

These are done via the Plant’s control system and/or safety system, but often these themselves are not analyzed for deviations. What happens when the DCS (Distributed Control System) or PLC (Programmable Logic Controller) or SCADA (Supervisory Control and Data Acquisition System) or even the SIS ( Safety Instrumented System) does not work as expected?

This is analyzed using the HAZOP technique and the HAZOP Professional should know how this is done and include it as part of the study. You can easily learn this when you take the Abhisam HAZOP Professional course.

Where can I learn more?

Most other HAZOP courses do not cover these three things at all, even though they are key to carrying out a complete and good HAZOP Study. However, you can easily learn this in the Abhisam HAZOP Leader course as well as the HAZOP Professional course.