When pilots go item by item through a preflight checklist or climbers repeat their tie-in safety checks for the nth time, they are removing uncertainty. This way, the pilot can be certain the flaps are in the correct position for take-off, and the climber can be certain he doesn’t become airborne due to missing a loop or messing up a knot.
If you’re doing routine electrical work, it can be easy to assume you’re safe rather than actually know you’re safe. Your first defense is to avoid thinking of any electrical work as routine. Always start by viewing it as something dangerous — even lethal — until you prove otherwise. You have many aids at your disposal. Let’s review some of them.
- Knowledge of operation. Knowing how something works is key to avoiding simple, stupid mistakes. What is the theory of operation? What should happen if you put this switch in that position? If you de-energize? If you re-energize?
- System drawings. These can help you with the knowledge not so much of operation but of execution. Ladder logic diagrams and similar will help you understand how individual components interact.
- Signs. When you enter a space, can you quickly determine where the fire extinguishers are (look for the red stripe near the top of a column)? The exits? Emergency eye washes? First aid kits? All of these are clearly marked with some system or another, so learn the system for the given facility.
- Operations personnel. The equipment you are working on technically belongs to the operators. They can inform you of anomalies in performance, sound, and even smell. Ask them. If they have nothing to report, you have removed some safety doubt. They can also tell you what else is going on in the area that may affect your safety.
- Job briefings. When conducting these, some people do a dog and pony show to avoid wasting everyone’s time with mundane information we all know. Others, when conducting these, act as if nothing in the world is more important. Make a point of being in this latter group. Don’t assume everyone knows what you know or should know it. Be thorough and communicate clearly. It’s far better to be a little bored rehashing something than to have the excitement of an electrocution or arc blast.
- Procedures. These exist for several reasons, and one of those is to ensure people do not skip important steps. If your procedures suffer badly from verbosity or have some other defect, that doesn’t give you a license to skip through them to get to the good parts or skip them entirely and wing it. If you don’t like a given procedure, mark up a printed copy of it as you go. Better yet, ask a supervisor to witness this as you go through it. Maybe the supervisor can be the one marking up the printout as you describe the needed changes.
- Covers. Don’t remove more covers than you have to for a given part of a given job. Aim to have covers off for as little time as possible. That is, the cover for C31 needs to be on until you need access to C31 and when you’re done working in C31 you put its cover back on.
- Tool counts. Not only do you save replacement costs by making sure you have the same tools that you started with, you also gain certainty that when you energize that bus your wrench won’t short two phases together and blow everyone to Kingdom Come.
- Personal protective equipment (PPE) and test equipment. If you ensure that what you’re using is rated for use in the environment you are using it and that it’s in good condition (no frayed fall protection harness, no damaged insulation on test leads, etc.) and that you are using it properly you can be certain that it will protect you from the hazards it’s intended to protect you from.
- Double checks. Using a DMM with the test leads in the mA jacks will not protect you from the hazards of a 480V bus. Such a gross error can be prevented by double-checking the set-up before approaching the bus with it. If you’re busy chatting while you are checking, then you’re not really checking. Stay focused.
Of course, it is not possible to entirely eliminate every hazard. Strange things happen. But the more concrete steps you take to reduce or remove safety uncertainty, the safer you will be.
