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An arc flash is an uncontrolled release of electrical energy that can cause severe burns, blindness, or even death. While no calculator can replace proper safety training, an arc‑flash assessment tool helps you estimate the potential energy that could be released during a fault and guide the selection of protective gear.
Begin by opening one of the free online arc‑flash calculators available in the Resource Section below. These tools are designed to provide quick, reliable estimates.
Select the equipment type from the “Equipment Type” or “Equipment Class” drop‑down menu. The terminology may differ between calculators, but the first choice always requires you to specify the equipment you are working with.
Input the values for the “Bolted Fault” current, “Clearing Time,” and any other parameters the calculator asks for. Depending on the tool, you may see drop‑downs, sliders, or text boxes. More advanced calculators allow you to account for multiple fault scenarios.
Click the “Calculate” or “Calculate Arc Flash” button once all fields are complete. The tool will display the estimated arc‑flash incident energy and, in many cases, recommend the appropriate PPE class.
These calculators are for estimation only. Always follow the latest NFPA 70E guidelines and your organization’s safety procedures before working on or near energized equipment.
