We all know that the primary work procedure required by both NFPA 70E® and federal regulations is that electrical equipment be placed into an electrically safe work condition before work has begun. [Here in the northeast, if the facility or the specific equipment has no ability to be supplied by automatic secondary power, I might consider that the loss of power (or establishing an electrically safe work condition) is not a concern to the owner and that energized work would never be necessary. If a sudden, unexpected power loss is not a concern, how could a scheduled outage possibly be?] We also know that there are only three reasons for permitting energized work. These are increased hazard, increased risk and infeasibility. I don’t intend to address what these mean or whether the energized work is justified. For this discussion I am going to assume that these reasons have been used to justify the work.
Assume something along the line of a patient on life support or a process that has the potential to ignite a hazardous location. If the equipment is shut off, the patient will die. The building will blow up if the process is stopped. You surely don’t want either to occur. These are typical reasons someone uses to illustrate the need to justify energized electrical work. What is surprising that although both of these are used as examples, most often neither is the reason I am given as justification for energized electrical work.
If you claim justification of the energized work to keep the patient alive or the process operating, doesn’t that meet the requirement? Not really. Just making the claim does not make it true. It could be true if that single, critical piece of equipment can be repaired while staying in full operation. If it is not a single, critical piece of equipment, is the energized task justified? What happens if the equipment fails before the justified work even begins? What if the equipment cannot be repaired? Justified energized work does not guarantee uninterrupted equipment operation. What happens when the worker drops a screw into the equipment and the equipment is accidentally and suddenly shut-down? That patient’s life that you used to justify the energized work has ended. That explosion that you wanted to prevent has leveled the building. Something you tried to avoid has occurred. And if those results did not or will not occur due to equipment failure, was the energized work truly justified?
We have all seen photographs of things gone horribly wrong when work is conducted on energized equipment. Before the task began do you think they thought; today is the day I will get injured or will die. Did they think; I will make a mistake that will shut this equipment down. Or did they think; it will not happen to me. Either way they were injured when something did not go as expected. If the work was justified and they followed NFPA 70E, their injuries should have been recoverable. Good for the worker but what about the reason for the justification?
On the other hand, there is no way that those pieces of equipment were brought back online quickly enough to prevent this hypothetical death or explosion from happening. The down time in a majority of these cases was considerably longer than a scheduled shut down would have been. Should they have anticipated all the possible faults? Should they have had a “Plan B”? If they had a Plan B, shouldn’t they have had it in operation so that the work could be performed in an electrically safe work condition? Was moving the patient to another area or using other life support equipment possible? Should they have considered how long the equipment could be de-energized before the situation would turn bad? Maybe the process could be shut down for more than an hour before the hazard became an issue and a five minute de-energized repair is the way to go.
This does not mean that there is never a legitimate reason for justifying energized electrical work. What it means is that often it is still selected as the norm rather than the exception without truly justifying the task or considering other things. You should consider everything before putting your worker at risk by performing energized electrical work.
Next time: I am glad I don’t have to make the decisions some of you make.