We received some great feedback from this month’s blog post, “13 Ways to Sabotage Your HAZOP.” Specifically, one of our readers had some very thought-provoking questions that are particularly relevant during these cost-cutting times. Fortunately, Randy Richardson, our RiskCom HAZOP expert, is here to help!
Q1: How do you demonstrate the value of good HAZOP and having 12 folks huddled around a table for months on end….
The value of a HAZOP (aside from where it is required, e.g. by PSM or as part of a safety case) is that it is a proven technique for improving the design. A well-run HAZOP invariably catches mistakes in the design, at a point where they are still relatively inexpensive to correct. It’s always much cheaper to fix drawings than to fix steel, especially offshore!
You can improve the efficiency of your HAZOP, and minimize the time that it takes, by strict adherence to HAZOP basics, such as not spending workshop time trying to design changes, and by keeping breaks short and getting back from them on time. Also, 12 people in the HAZOP may be more than you need; as we noted in the blog, something around six to eight is ideal.
Q2: What is the threshold is for re-HAZOP because
- There’s a suspicion you have actually made more than one of the 13 infuriating mistakes or
- You have made some changes to a ‘standard’ design that’s already HAZOP’ed over and over?
1. Most of the 13 mistakes won’t invalidate a HAZOP, they’ll just slow it down or make it less efficient. The two that are most likely to give fundamental problems are, first, letting people get away with saying “It Can’t Happen” when what they really mean is that there are multiple safeguards in place; and second, confusing the risk definition, so that you are giving the frequency as how often the accident scenario will occur rather than how often the consequence will occur.
The first mistake – the “It Can’t Happen” fallacy – will invalidate the discussion for those scenarios where the facilitator has allowed this to take place. It won’t be a problem for all scenarios, or even for most of them. And even for the scenarios where this mistake has been made, it may not be fatal. Chances are that the scenario, when properly evaluated, will turn out to have a very low risk. You may be able to take care of your “It Can’t Happen” blunders with a fairly short session involving a minimal number of people.
If you have committed the second mistake, you will be seriously overestimating the risk and your HAZOP will have a lot of very high-risk accident scenarios. This should trigger some consternation during the workshop, probably before you have gotten very far into it. If you to have a competent facilitator, you should not make this mistake to begin with.
If you suspect that you have made this particular mistake (your facilitator is less than competent), and the workshop is already over, you should re-examine your high-risk scenarios and determine whether the assumed risk ranking is valid. This can be done with a small team, which can then communicate the results of their finding to the HAZOP team as a whole to make sure that they concur. The good news is that this mistake won’t result in dangerous scenarios being overlooked, it will only result in the risk being overestimated.
2. When you make changes to a standard design, it may be necessary to re-validate your HAZOP to verify that the changes have not affected the risk in a fundamental way. This doesn’t need to be a months-long process that ties up half your staff. I have done revalidations where there were only five people in the room, including myself.
And you don’t need to recreate the HAZOP from scratch. Go through the existing HAZOP, determine the areas that are affected by the change, and then go through the HAZOP scenarios for those areas and determine what the change will do to the risk.
There’s no way to make the pain associated with a HAZOP go away completely. But, “no pain, no gain.” If you do the HAZOP smartly, the gain can be well worth the pain.