I’ve conducted hundreds of electrical safety training classes throughout the United States, and I often hear maintenance supervisors say: “We don’t need an arc flash study because we don’t do energized work. We contract it out.”
Then I ask, “If that's the case, may I inspect the maintenance team’s work areas? I would like to collect all the voltage meters and testing equipment and take them home with me. You don’t need them, right?”
I don’t actually say this, but I've thought it many times. If you believe that you and your maintenance team do not engage in live electrical work, I encourage you to read on because you might change your mind by the end of this article.
1) Do you know the definition of "working on" as it applies to energized electrical work?
2) Can your maintenance team do their jobs without using voltage testers?
3) Do you follow a LOTO program?
4) Do you hire electrical contractors for your work?
Let's answer each of these questions.
Many workers believe that troubleshooting and testing is not energized work. I used to believe that as well, but I was wrong. There are two categories of energized work 1) Diagnostic and 2) Repair.
Diagnostic includes troubleshooting, testing and inspection. If a worker intends to come in contact with energized electrical conductors or circuit parts, the worker is engaged in energized work. Coming in contact does not just mean parts of the body. It includes tools, probes and test equipment, which are considered to be an extension of the worker's body.
Repair involves alteration of electrical equipment such as replacing components and tightening connections. If your maintenance team engages in troubleshooting and testing, they are doing energized work.
Either way an arc flash risk assessment is required to quantify the risk and guide the worker in the proper selection of PPE.
We established above that diagnostic work is energized work. If your maintenance team truly doesn't engage in energized work, they don't need meters or testers. Anytime the panel covers are off or the doors are open to expose the worker to energized conductors while interacting with electrical equipment, the worker is engaging in a dagnerous task. An arc flash risk assessment is again required in these cases.
Having a LOTO program does not exempt a company from having an arc flash risk assessment. Even if you have a policy of deenergizing before engaging in electrical work, it is still considered energized work until absence of voltage is confirmed. In other words, all steps of the LOTO process are considered energized work until a voltage tester is used to confirm that the power is off. PPE is crucial until the absence of voltage is verified. An arc flash risk assessment is the guide to selecting the proper PPE.
OSHA and NFPA both outline the host and contractor responsibilities. The main responsibility of the host is making the contractor aware of any hazards associated with the electrical system. This means making the contractor aware of the arc flash and shock risk involved at all equipment and in all areas. An arc flash risk assessment is not only vital, but is required to fulfill this obligation.
With all of this in mind, the following are just a small sample list of tasks that are energized work.
• Removing and replacing panel covers
• Opening disconnect or MCC doors
• Removing the dead-front from a panelboard
• Taking voltage or current readings (using a multimeter)
• Replacing breakers, fuses, or other parts
• Landing wire or tightening connections to a lug
• Moving conductors
• Troubleshooting/diagnostic testing
• Visual inspections
• Thinking it is “dead” when it is “live”
Before reading this article, did you believe that all of the above tasks were energized work? It is a common misconception that live electrical work consists only of repair tasks such as changing a breaker or tightening a connection. Many workers do not view diagnostic work as energized work, even when the equipment on which they are working is live. I once believed that myself.
Diagnostic work is not only considered live electrical work, it can be just as dangerous as changing a breaker or repairing live electrical equipment. As a matter of fact, troubleshooting is the leading trigger of arc flash events, causing almost one-fourth of all arc flash events. This makes sense. During troubleshooting, a worker is typically opening doors or removing panels to expose live parts. In addition, the worker is often utilizing some type of measuring or metering tool, such as a voltage meter, inside the panel. Moving conductors are also common. Interactions such as this, with the equipment inside the panel, could trigger an arc flash event.
Now that you have read further, do you still believe that your workers do not engage in energized work? If so, great. Let’s keep it that way. If, however, you have changed your mind, congratulations. This is the first step in recognizing the risks involved when working in an energized environment. You can now focus on risk assessment and protection.
The bottom line is this: an arc flash risk assessment is required whether you and your maintenance team engage in live electrical work or not. Even if you hire contractors for all live electrical work, your company is still responsible for identifying and making contractors aware of the risks involved in doing the work. An arc flash label and risk assessment go a long way to accomplish this. In addition, anyone performing live electrical work should be provided with the necessary protection and PPE to minimize the risk. Employers bear the responsibility for their workers, while contractors bear their own responsibility. In both cases, the host facility is responsible for making the worker aware of the hazards.
Bobby Lindsey – CESCP
Mitchell & Lindsey – President
M: (502) 836-4217