5 Rules of Process Engineering - Rule 5 - Live with the Consequences

In my mind, this rule is the hardest one if you care about what you do. You will make mistakes. You will design things incorrectly. You will take shortcuts that you shouldn’t have taken. With that understanding, you need to be prepared to own up to the mistakes you make.

I noted you will make mistakes. This is fact; don’t think you will be immune. If you can make your mistakes on small items rather than critical ones, great, but it is difficult to isolate. Of course a robust QC system should find the mistakes before anything gets sent to a client or built, but it won’t always happen. A couple of recent examples have involved bridge construction in Alberta; one bridge was 11 cm short of the support pilings, another had the beams buckle during installation. Someone, somewhere made a mistake that did not get caught until too late.

One key learning I have had is that given that you will make mistakes, it is really important how you deal with them. If you find them yourself, rather than someone else finding them, you are ahead. If you do the work required to resolve the issue, you will earn respect. This might mean you work the weekend to figure out the answer to the mistake discovered on Friday.  

You will learn, over time, when your utmost care and attention is required, and when to balance thoroughness against efficiency. Conceptual and preliminary design work involves a lot of “close enough” decisions. You need to be close, but you don’t need to be precise. All the bases and assumptions will probably change anyway, so do you need to exactly define a mass and energy balance including all minor components? The flip side is that when doing detailed design on safety critical systems, you need to be sure. You can always oversize a piece of steel with consequences in cost and maybe schedule, but over- or under-sizing process equipment can lead to significant changes in how things actually work and resultant safety or environmental outcomes. For example, a significantly oversized packed scrubber might actually result in poor gas-liquid contact and recovery of a toxic material. An oversized heat exchanger might underperform due to a change in flow characteristics leading to less turbulence and/or increased fouling. Over-powered agitators can erode themselves and the vessel they are in without an improvement in process results.

When you make a mistake, and you will, own up to it and do your utmost to fix it.