But when everything is re-assembled, do we simply turn everything back on? Well no. Despite up to six years of analysis, we may have missed something. Every change is a risk, and we’ve changed everything. So, what do we do? Typically, all vacations are cancelled. All vendor representatives and services contractors are summoned to the site. Everyone starts putting in 12-hour days, and the plant is started and is brought up to 5% of capacity. Every technician, vendor and engineer is walking around the site, looking at things, listening to them, feeling them if it’s safe to touch them, and sometimes even sniffing at them. The plant operators, their supervisors and the engineers are clicking through the HMI screens, looking at every bit of each screen to see if both the plant and the screens are working as expected. The cyber people are looking at memory usage, network communications, and logs.

Nobody and nothing is perfect. We find problems, and we fix them. We bring the plant up to 25% of capacity. To 50%. And eventually to 100% of capacity. It’s been two weeks. Everyone is exhausted. Most of us haven’t seen our families in all that time, and still, we look for problems. We find fewer and fewer new problems. Each problem is triaged. Low-priority problems are documented and handed off to the team preparing for the next outage, three years from now. We start to stand down. At three weeks, the plant is at full capacity, the vendors have all gone home and we are back to a normal staff. Success!