Panel Schedules and Plant Safety
Panel Schedules
Having up to date and accurate panel schedules is an integral part of safety. They can save time in emergencies and ensure the safety of maintenance staff and contractors working on or installing equipment. Accurate schedules help team members identify what machinery is energized by each breaker and gives them a point of reference to lockout and tag out for safety purposes.
Proper labeling practices are almost as necessary, making it possible to identify equipment to be de-energized even in a situation where there are identical machines controlled by multiple breakers or people in the plant that may be unfamiliar with the facilities.
Why It’s Important
If the need arises to de-energize a machine and the panel feeding it is not labeled, it can cause significant issues. How do you know what breaker to shut off? You may have to shut off several breakers until the proper one is identified, disrupting operations in the rest of the plant. If a machine isn’t properly labeled, and there is an emergency, how will employees know what panel is in control?
For example, there was a factory that utilized an acid etching as one step of its manufacturing process. The panel schedule and labeling were not accurate or up to date. An employee from maintenance needed to perform lockout and tag out (LOTO) on a piece of equipment so that he could repair it. He accidentally turned off the breaker that controlled a robot in the acid etch room. The robot was stopped in mid-process and had to be reset and rebooted. The robot-controlled a timed process moving material through washing, multiple acid baths, and a rinse cycle before depositing the finished product onto a conveyor belt. The content stayed in the acid too long and was ruined, causing the ruin of valuable products.
Accident Prevention
The plant could have avoided this situation easily. Employees must never turn off breakers unless they know what they feed. If the machines in the plant were labeled correctly and panel schedules filled out correctly, then it is unlikely that this accident would have occurred.
OHSA standards require companies to fill out schedules in all panels, including any unused/spare breakers. It is a widespread issue to find spare breakers in panels that are turned on and not labeled. If a breaker is unused, it is an industry-standard to label it “spare” on the panel schedule and keep it turned off.
Spare Breakers
Failing to honor this practice can be dangerous. Unused and unlabeled breakers may still connect to wire conductors. Since they do not feed equipment, there is no way of knowing the path of those live wires or where they terminate.
For example, a contractor was helping to demolish the wing of a building in preparation for a remodeling project. The panel schedule was not up to date, and spare breakers were not labeled and turned off. The contractor was inside a crawl space and touched a wire dangling in the air. He was shocked by a live wire that he believed was disconnected. Fortunately, this worker was not seriously injured, but this accident could have been serious or even fatal.
Equipment Labels
There are many ways to label equipment — a simple machine label with a name and panel feed stenciled on it is better than nothing. Equipment labels can help with LOTO procedures and PPE implementation.
By taking a little bit of time to fill out panel schedules, label breakers, and equipment, companies can save money and downtime. It can improve plant safety and keep your company in compliance with OSHA regulations. It is a practice that makes good business sense, and it is something that will make employees safer in the long run.